GTA
All Springer/NP/PCP Air Gun Discussion General => PCP/CO2/HPA Air Gun Gates "The Darkside" => Topic started by: Wolverineshooter on September 26, 2017, 06:33:12 PM
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I am wondering when the pellets have the same shape and weight, if 0.177 should have less air resistance (higher BC) than 0.22. 0.177 may also have a more stable flight. My reasoning is that there is less collision with air molecules with 0.177 due to smaller surface area than 0.22. Am I right?
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Essentially correct.... There are two factors in pellet drag, the Form Factor (FF) and the Sectional Density (SD).... The SD can be thought of as the "weight per square inch of bore area", in other words it's ability to maintain velocity against the air resistance.... SD is calculated from....
SD = Weight (grains) / 7000 / Caliber (inches) ^2 .... The 7000 changes the weight in grains to lbs....
The Ballistics Coefficeint (BC) is found from....
BC = SD / FF .... If the shape is identical, then so is the FF.... Wadcutters have more drag, so a high FF.... Round Nosed pellets have less drag, so a low FF....
If the weight is constant, then the SD is higher in the smaller caliber.... For a 10 gr. pellet....
SD (.177 cal) = 10 / 7000 / (0.177 ^2) = 0.046
SD (.22 cal) = 10 / 7000 / (0.22 ^2) = 0.030
Round Nosed pellets tend to have a FF of about 1.5, and IF the two pellets in question had the same FF....
BC (.177 cal) = 0.046 / 1.5 = 0.031
BC (.22 cal) = 0.031 / 1.5 = 0.021
In fact the .22 cal pellet would tend to be shorter and fatter in proportion, so the FF would likely be greater, dropping the BC even lower than this calculated value.... If the FF of the .22 cal, 10 gr. pellet was 2.0, the BC would be about 0.016....
Bob
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I saw a video of Steve Shally revisiting the power and shootability of .177 cal.. It was educational for me because of what I was reading in some forums was definitely going with .22 cal. If you can tune a rifle to shoot a .177 cal at 10.2g or greater past the 800 mark, the pellet carry enouf energy to drop a small game for sure if you do your part..Here is the link to the video..https://www.youtube.com/watch?v=6KmXlpVZ_Ew (https://www.youtube.com/watch?v=6KmXlpVZ_Ew)
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Bob beat me to it, and at it. Excellent explanation by rsterne.
But I'll add a little something to the topic.
A 16 grain .177 diabolo pellet will be a bit longer than a 16 grain diabolo .22, & that little longer length can have a negative effect on stability, depending on the twist rate of both barrels & on how fast they are going when they leave the muzzle.This can negatively affect the pellet's stability in flight.
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A .177 pellet will require a faster twist rate than a .22 cal, even for the same length pellet.... Twist rates are calculated in calibers, and then converted to inches.... You need twice as fast a twist (in inches) in a .177 cal than in a .357 cal for the same bullet proportions....
Bob
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Thanks Bob and Ricky for the excellent explanations. As for the twist rate, I assume the gun manufacturer has done the job properly, creating the twist rates based on the calibre.
So for pellets of the same weight and started with the same speed, the 0.22 pellets will have more wind drag and therefore will deliver less hit, but 0.177 may be less stable if it is longer.
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Thanks Alain. That Daystate Wolverine is amazing!
0.177 will have advantage in terms hitting power compared to a 0.22 pellet of same weight and starting with the same speed due to less wind drag. But may be less stable if it is longer. From this video 0.177 appears to be still very accurate. Very informative!
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Let's say the pellets weigh 15gr, with muzzle speed 700fps, 0.22 BC=0.016, 0.177 BC = 0.031 as in the case Bob calculated. Then the energy will be:
Yards 0.22 energy 0.177 energy
0 16.32 16.32
10 14.05 15.10
25 11.29 13.47
50 7.86 11.16
100 3.7 7.7
So 0.177 will have more killing power at a longer distance.
What it takes for the 0.22 to match the killing power of the 0.177? Let's increase the speed for the 0.22 to match the killing power of 0.177:
0.22 Muzzle speed Muzzle power Distance Hitting power
700 16.32 0 16.32
727 17.60 10 15.10
768 19.64 25 13.47
852 24.17 50 11.16
1170 45.59 100 7.7
So if your goal is short distance hunting, then 0.22 may do better if it has more power to begin with. But 0.177 will have advantage in the long distance that 0.22's higher initial energy may not be sufficient to compensate.
Did you see that it requires 46fpe for 0.22 to match the killing power at 100 yards of 0.177 with a muzzle power of 16.32? just because of less drag in 0.177.
The pellet makers should publish the BCs to help us with the choice of pellets.
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Thanks all for excellent explanation.
Unfortunately extra heavy .177 pellets are unstable by using standard barrels.
I am thinking that caliber .133 will be the future.
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Thanks all for excellent explanation.
Unfortunately extra heavy .177 pellets are unstable by using standard barrels.
I am thinking that caliber .133 will be the future.
Based on Bob's explanation, the twist rate of the gun is based on the caliber. So beyond caliber, other factors affecting the stability would be the length of the pellet due to more contact to the air. Not sure how much impact this will have. The surface area on the side of the pellet is proportional to its length, as well as its radius. So does this mean two pellets with the same shape and length but different radius, the fatter one will be less stable?
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There seems to be quite a bit of confusion in this thread about bullet stability.... Perhaps by using the Kolbe Twist Calculator you could answer many of your own questions....
http://www.geoffrey-kolbe.com/barrel_twist.htm (http://www.geoffrey-kolbe.com/barrel_twist.htm)
As far as comparing pellets of equal weight in different calibers, that is really not practical, for the same gun will NOT launch the smaller pellet as fast.... or alternately it will launch a heavier, larger caliber pellet at the same velocity.... While your numbers comparing equal weight pellets is interesting, it is not really practical, nor does it apply to a gun having the barrel changed between .177 and .22 cal in the real world.... It is sometimes easy to lose sight of the forest for the trees.... Generally, when a gun is made in two different calibers, shooting "normal" ammunition for that gun.... the larger caliber will provide more FPE and hence more "killing power" downrange.... The drawback is that it will not have as flat a trajectory as the smaller caliber....
Bob
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Thanks all for excellent explanation.
Unfortunately extra heavy .177 pellets are unstable by using standard barrels.
I am thinking that caliber .133 will be the future.
My BSA Buc loves the 15g Sniper Magnums... I am pretty sure all BSA barrels are 1:19 twist... Pellets make their own rules as far as twist... they need very little in comparison to slugs/bullets...
then there are foster slugs that do well in the right smooth bore and they spin very slowly also...
Pellets because they come in different head shapes, waist configuration etc in the end will like what they like at different velocities...
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There seems to be quite a bit of confusion in this thread about bullet stability.... Perhaps by using the Kolbe Twist Calculator you could answer many of your own questions....
http://www.geoffrey-kolbe.com/barrel_twist.htm (http://www.geoffrey-kolbe.com/barrel_twist.htm)
As far as comparing pellets of equal weight in different calibers, that is really not practical, for the same gun will NOT launch the smaller pellet as fast.... or alternately it will launch a heavier, larger caliber pellet at the same velocity.... While your numbers comparing equal weight pellets is interesting, it is not really practical, nor does it apply to a gun having the barrel changed between .177 and .22 cal in the real world.... It is sometimes easy to lose sight of the forest for the trees.... Generally, when a gun is made in two different calibers, shooting "normal" ammunition for that gun.... the larger caliber will provide more FPE and hence more "killing power" downrange.... The drawback is that it will not have as flat a trajectory as the smaller caliber....
Bob
Based on the anti-squirrel's casual experiment in the other thread, https://www.gatewaytoairguns.org/GTA/index.php?topic=132889.0, (https://www.gatewaytoairguns.org/GTA/index.php?topic=132889.0,) which I quote below:
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I tested this using my 2240 using 15 grain Sniper Magnums in .177 and 15.4 grain Gamo Redfires in .22. Swapped barrels out in one session and still surrpised over the validation. The .22s were a hair faster, 540 FPS versus 535 FPS. I was impressed, so I then compared 13.1 grain Skenco New Boys in .177 to 13.4 grain JSB Exact RS domes in .22. 545 in .22 versus 540 in .177. Yes, I know the pellets aren't the exact same weight, but close enough for my very unscientific test.
The math is what I trust implicitly, as we had to work out stuff like this when I was in Nuke Power School. I don't miss doing those equations, but the lesson stuck, and Bob, Gary, and Ribbs are on the money.
For ease of testing the 2240 is a near ideal platform as barrels are dirt cheap and CO2 is sorta self-regulated. And my testing also confirmed what Bob says where if I want more oomph outta my 2240 as a 1740, then I need a longer barrel. I now have a 24" barrel (though I admit it looks silly as a pistol with a 24" barrel!).
Side note: maybe that's where all my CO2 powerlets have gone?
Second side note: how is it people strip out those breech screws? I file my hex keys flat so they fit precise, ya know. Nary a problem :D
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What I am seeing here even though the 0.22 is faster and have more muzzle energy, but by not much. So BC will be a more dominant factor in the performance.
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Yes, in anti-squirrel's tests, the velocities were close, although he didn't state if the barrels were the same length in both calibers.... A common .177 cal conversion on the 2240 (which has a 7.5" barrel) is to use the 10.1" barrel from a 1377.... My personal experience, using the same barrel length in different calibers, shows a much larger difference in FPE in favour of the larger caliber, when all other factors are kept the same....
The very title of this thread is problematic.... If a .177 and a .22 cal pellet are the same weight, they will NOT be the same shape....
Bob
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Bob - I agree, as that is the first thing I thought of when I read the title and first post . . .
Greg,
You have created an unrealistic specific set of defined conditions intended to be able to effectively reach a conclusion that you seem to want to reach. I am not sure why . . .
Especially in the world of PCPs (which is what this forum is targeted at), you are never going to find a situation where you will be able to put more power downrange with a .177 than you can with a .22 unless you intentionally "handicap" the .22 with a sub-optimal set of conditions or tune. That is exactly what you did in your hypothetical question in this thread - as evidenced by having to have the gun that shoots the two pellets at the same speed be uniquely tuned to use less air for the .22 to get to that condition. So even if the pellets could be "the same shape" to get the answer you want, the .22 pellets are not being shot at an energy level that they would achieve from the same conditions in the shot cycle.
Bottom line, in pretty much any metric you want to use that deals with either efficiency, power or retained energy, the larger calibers are going to "win" - because by definition if the shape is the "same" but just scaled for caliber, the larger caliber pellets will be heavier, AND have a higher BC, AND will be shot more efficiently in terms of energy extracted from the air charge (to a point - an air charge that could effectively fire a .177 may not fire a .357 pellet).
Now, if you are talking metrics about putting a pellet on target at a longer range, that is completely different than fps, FPE, and all that. They matter, but they are not the end game metric there . . .
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Yes, in anti-squirrel's tests, the velocities were close, although he didn't state if the barrels were the same length in both calibers.... A common .177 cal conversion on the 2240 (which has a 7.5" barrel) is to use the 10.1" barrel from a 1377.... My personal experience, using the same barrel length in different calibers, shows a much larger difference in FPE in favour of the larger caliber, when all other factors are kept the same....
The very title of this thread is problematic.... If a .177 and a .22 cal pellet are the same weight, they will NOT be the same shape....
Bob
Yeah, the difference is less than what I expected too. If barrel lengths are different that explains.
Well of course the shapes will not be eactly the same, just a way to say they are comparable except radius
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Just notice
Larger caliber is able stabilized the pellet more by larger shirt
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Let's say the pellets weigh 15gr, with muzzle speed 700fps, 0.22 BC=0.016, 0.177 BC = 0.031 as in the case Bob calculated. Then the energy will be:
Yards 0.22 energy 0.177 energy
0 16.32 16.32
10 14.05 15.10
25 11.29 13.47
50 7.86 11.16
100 3.7 7.7
So 0.177 will have more killing power at a longer distance.
What it takes for the 0.22 to match the killing power of the 0.177? Let's increase the speed for the 0.22 to match the killing power of 0.177:
0.22 Muzzle speed Muzzle power Distance Hitting power
700 16.32 0 16.32
727 17.60 10 15.10
768 19.64 25 13.47
852 24.17 50 11.16
1170 45.59 100 7.7
So if your goal is short distance hunting, then 0.22 may do better if it has more power to begin with. But 0.177 will have advantage in the long distance that 0.22's higher initial energy may not be sufficient to compensate.
Did you see that it requires 46fpe for 0.22 to match the killing power at 100 yards of 0.177 with a muzzle power of 16.32? just because of less drag in 0.177.
The pellet makers should publish the BCs to help us with the choice of pellets.
It open more question about efficiency... And as far as twist rate, the discussion was discussed in another tread and someone mention the FX SMOOTH TWIST.. The efficiency in a heavier pellet could be increased at a certain pressure with the smooth twist due to less drag..
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The basic concept of using the same weight pellet in .177 and .22 cals is handicapping the .22 cal.... You must detune the .22 cal for that to take place, either by barrel length, pressure, porting, or some other means of artificially restricting the performance of the .22.... Then you are looking at the best possible case for the .177 cal, by choosing a very heavy pellet, with an excellent SD and potential BC.... With the question so heavily weighted in favour of the .177 cal, is it any surprise that you can "prove" that is it superior to the .22 cal ?....
Reality is what counts.... If this was reality, we would be pursuing smaller and smaller calibers to increase killing power, instead of the surge in popularity in Big Bore that is actually occurring....
Bob
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The basic concept of using the same weight pellet in .177 and .22 cals is handicapping the .22 cal.... You must detune the .22 cal for that to take place, either by barrel length, pressure, porting, or some other means of artificially restricting the performance of the .22.... Then you are looking at the best possible case for the .177 cal, by choosing a very heavy pellet, with an excellent SD and potential BC.... With the question so heavily weighted in favour of the .177 cal, is it any surprise that you can "prove" that is it superior to the .22 cal ?....
Reality is what counts.... If this was reality, we would be pursuing smaller and smaller calibers to increase killing power, instead of the surge in popularity in Big Bore that is actually occurring....
Bob
I dont want you to be OFFENDED by what I am about to say.. The surge in big bore popularity is related to the opportunity to hunt bigger game that was intended for powder burners until recently.. I think the cost in the bigbore be slightly less than 5 years ago is a big part of the surge too... I dont think it is negative to ask question about efficiency in the small bore domain because if you can have the same KILLING POWER in a .177 in longer range then a .22 , it is advantageous to hunt with the .177 in the capacity to use the air more efficiently.. LESS REFILL= MORE HUNTING.. I dont want to hunt rabbits with a 100FPE gun..
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The same debate goes on in the powder burner community with the 300 win mag and the 6.5 creedmore.. On the SNIPERFORUM you can follow the open discussion and GOOD ARGUEMENTS are discussed in both camps..
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Yes, in anti-squirrel's tests, the velocities were close, although he didn't state if the barrels were the same length in both calibers.... A common .177 cal conversion on the 2240 (which has a 7.5" barrel) is to use the 10.1" barrel from a 1377.... My personal experience, using the same barrel length in different calibers, shows a much larger difference in FPE in favour of the larger caliber, when all other factors are kept the same....
The very title of this thread is problematic.... If a .177 and a .22 cal pellet are the same weight, they will NOT be the same shape....
Bob
Hit the nail square on the head. I used a stock .22 barrel and 10.1" .177 barrel off my 1377, so I was already doing exactly what we DON'T want- putting things in favor of the .177. Then using a .22 Gamo Redfire, which is a hollow-point with a polymer tip and comparing it the ballistically superior Sniper Mag with a rounded nose that also weighed a teensy bit less... and the .22 despite all the shortcomings still came out on top. I figured the .177 would come out on top and I was wrong.
The test with the 13-grainers was similar... even though I was skewing things with an advantage toward .177, the .22 still outperformed. This is when I dusted off my books and started doing math. And the math validated the results.
Summary: I enjoy my .177 guns a lot, but with all other things equal or slightly skewed in favor of .177, the .22 still came out on top. And this is why everybody should build these Lego guns. They validate all the mathematics we tried to forget after graduation. 8) ::) ;D
My personal choice: For a given platform, I try to go with the heavier pellets in PCP/CO2/Pumpers. When I eventually have more play money, this is why I want to scrounge up a .20 barrel for building a 2040, as well as- at some point- build a 2540 ie: .25 barrel.
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I dont want you to be OFFENDED by what I am about to say.. The surge in big bore popularity is related to the opportunity to hunt bigger game that was intended for powder burners until recently.. I think the cost in the bigbore be slightly less than 5 years ago is a big part of the surge too... I dont think it is negative to ask question about efficiency in the small bore domain because if you can have the same KILLING POWER in a .177 in longer range then a .22 , it is advantageous to hunt with the .177 in the capacity to use the air more efficiently.. LESS REFILL= MORE HUNTING.. I dont want to hunt rabbits with a 100FPE gun..
Ah, but here's the thing. A super-high-velocity .177 tends to be less accurate at longer range because the pellets are longer and thus have a greater likelihood of dynamic instability, where .22 are shorter (for a given weight) thus suffer less likelihood.
I am ALL FOR reducing power in a .22 airgun versus cranking a .177 up to volume 11. This is a matter of picking the right tool for the right job. Powderburners- due to the inherently faster (supersonic) projectiles, do not have to deal with the nutating action/dynamic instability at typical airgun pesting ranges (random number of say 120 meters). And although there are plenty of hunters/pesters that can shoot longer ranges with .177, there's a very real reason why bore size has steadily increased in longer range competition. To carry the same energy of a .22, the pellet has to either be longer (to be the same weight) or move faster, and once you start creeping into the transonic territory, things happen that affect accuracy.
One thing I forgot to mention was my shot-count in my tests. 43 shots in .22, 41 in .177. Efficiency goes to .22. Dunno what outside factors there were, but that's what happened.
I won't talk about accuracy, since my tests concern shorter-range (under 40 yards).
And what it all really boils down to is you don't get to pick the pellet: your barrel does. And if it likes Eun Jin 16 grain .177 domes, go for it. None of my .177s do, so I go for the next best thing: H&N Sniper Magnums at 15.1 grains. But those trajectories are loopier than a 15-grain Gamo poly-tipped hollowpoint in .22 :D
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Barrel volumes in anti-squirrels tests.... .177 cal with 10.1" barrel = 4.07 cc.... .22 cal with 7.5" barrel = 4.67 cc.... This produced a slight edge for the .22 cal.... If the .22 cal had the same 10.1" barrel length as the .177 cal, the volume would have been 6.29 cc.... and the performance would have far exceeded what the .177 did.... The shot count should have remained the same, but the FPE could have increased by as much as a third, because it is well known that the 2240 with stock 7.5" barrel wastes a LOT of CO2.... How would the efficiencies have compared then, with equal length barrels?.... Not much doubt in my mind....
Bob
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Barrel volumes in anti-squirrels tests.... .177 cal with 10.1" barrel = 4.07 cc.... .22 cal with 7.5" barrel = 4.67 cc.... This produced a slight edge for the .22 cal.... If the .22 cal had the same 10.1" barrel length as the .177 cal, the volume would have been 6.29 cc.... and the performance would have far exceeded what the .177 did.... The shot count should have remained the same, but the FPE could have increased by as much as a third, because it is well known that the 2240 with stock 7.5" barrel wastes a LOT of CO2.... How would the efficiencies have compared then, with equal length barrels?.... Not much doubt in my mind....
Bob
Definitely barrel length is a big factor here, not so much about the shape of the pellets because the travel is so short within the barrel to make a difference. In the article I cited, the hypothetical example the author calculated, the efficiency of 0.177 is 15% vs 0.22 at 23%, it is a 50% increase in power. Although I think the author is talking about optimal power so 0.22 will have a longer barrel, but nevertheless 0.22 should have more muzzle energy.
Still BC will have a big impact for the life after barrel at the longer distance. I assume typical hunting would be short distance so 0.22 will have advantage over 0.177 in terms of efficiency.
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No reason you can't so the same (at least with PCP's, where are adjustable enough to get the output pretty close in speed). Rather than just using calculatores (which aren't really bad), suggest you actually get out and shoot them BOTH at range and a a good selection of test media (from really soft stuff to really thick/hard stuff).
NORMALLY, I'd prefer an airgun suinted to the power level needed for what I'm hunting and the ranges I expect to shoot.
BUT some times a new toy just has get some real world shooting in, even if it's pretty inapporpriate foe the game at ahnd. Really do not need a +50 foot pound .25 to nail a few pest birds, but getting some trigger time on the new toy seems more important.
An aside:
(PB related). Hunted two years with a buddy "Boo" (Yeah...nick-names are kind of a southern thing). Rabbits, squirrels, pigs, nutria, deer. He used a .375H&H for all of that. WHY?...becasue he had moose trip booked and paid for the next season and he wanted to get use to the recoil (which I do admit, is easier to deal with away from the bench and with your consentration on hunting.)
(Then again, he'd also run around the track or up statium stairs, with a 50 pound back pack for the same reason. Never saw such a dedicated hunter.)
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Given all factors are at least IDEAL. I disagree with keeping pellet weights the same when comparing two different bore sizes as that is VERY unfair...
.177 @ 18 fpe (10.3 gr jsb heavy) going 900 FPS will drop 13.94 inches @ 100y (2" scope height)
-Energy retained @ 100y= 9.6 FPE (51.81%)
.22 cal @ 32 FPE (18 gr jsb heavy) going 900 fps will drop 13.56 inches @ 100y (2" scope height)
-Energy retained @ 100y = 17.39 FPE (53.71%)
.25 cal @ 61 FPE (34 gr jsb heavy) going 900 fps will drop 12.31 inches @ 100y (2" scope height)
-Energy retained @ 100y = 37.07 FPE (60.63%)
If sectional density and ballistic co efficiency are tied together...then ultimately a pellet of the same weight will potentially do better the smaller the bore...
-Matt
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Barrel volumes in anti-squirrels tests.... .177 cal with 10.1" barrel = 4.07 cc.... .22 cal with 7.5" barrel = 4.67 cc.... This produced a slight edge for the .22 cal.... If the .22 cal had the same 10.1" barrel length as the .177 cal, the volume would have been 6.29 cc.... and the performance would have far exceeded what the .177 did.... The shot count should have remained the same, but the FPE could have increased by as much as a third, because it is well known that the 2240 with stock 7.5" barrel wastes a LOT of CO2.... How would the efficiencies have compared then, with equal length barrels?.... Not much doubt in my mind....
Bob
Definitely barrel length is a big factor here, not so much about the shape of the pellets because the travel is so short within the barrel to make a difference. In the article I cited, the hypothetical example the author calculated, the efficiency of 0.177 is 15% vs 0.22 at 23%, it is a 50% increase in power. Although I think the author is talking about optimal power so 0.22 will have a longer barrel, but nevertheless 0.22 should have more muzzle energy.
Still BC will have a big impact for the life after barrel at the longer distance. I assume typical hunting would be short distance so 0.22 will have advantage over 0.177 in terms of efficiency.
Here's where typical hunting becomes a point for discussion. I have no problem taking small game up to 30 yards with my .177 PP700 pistol. If it were a .22 I'd leave it the same depending or open it up a little to 35 or 40 as long as I can get the same accuracy. But my PR900 rifle- a .22- I feel confident in taking small to medium quarry in excess of 50 yards. I haven't found what it likes the most pellet-wise, but I'm sure that as per most SPA guns, it will prefer heavier pellets... Which suits me fine. Ad we have many folks here dropping quarry in excess of 80 yards. In powderburner terms, that's short distance. In airguns, that's a good ways off.
Bottom line is the energy should match the quarry. UK hunters take squirrel at 40, 50 and further yards with 12 FPE springers and PCPs. Why? It's all about precision. So in the end, being able to put a pellet where it inflict fatal harm to quarry is the intended desire, not putting a certain energy level at a certain distance. Case in point: I seen gut-shot squirrels hit with .22LR run up a tree and make it off and outta sight. And yet my 9 1/2 FPE Slavia 634 springer has taken multiple squirrel with absolutely precise headshots. Energy level is not as important as precision. So whatever gives the best accuracy is what I generally choose when it comes to pellets RE: weight/size etc.
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Well precision and energy are both important but of course if no precision then power is irrelevant. I wonder why UK shoots far with 12fpe, is it because their pellets have better BC? I would assume people here are just as accurate as Europeans, right?
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Not better BC, just more hold over.
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Why stop at 25?
If looking for the IDEAL...why not include larger bores...they can make it to 900fps too...and show the same progressive advantage.
(And when has this been news...sometime in the late 1600's...big projectiles pushed full-outdo better than little projectiles when pushed by the same pressure (or did match-lock shooter's get it wrong?)
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Well precision and energy are both important but of course if no precision then power is irrelevant. I wonder why UK shoots far with 12fpe, is it because their pellets have better BC? I would assume people here are just as accurate as Europeans, right?
Not really true about power being irrelevant. The more power you have, the less accurate you can be. With .177 I would agree, but .25 and above terminal shock plays a roll.
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Good that you admit that..."The more power you have, the less accurate you can be."...but I haven't found that quite the story. A .177/20/22/or 25 hole though the brain or heart on typical/tradtional airgun sized critters (squirrels to rabbits) seems to work just as well for me...might be that a larger pellet delivers more energy per inch of "meat travel", but if it doesn't smack the "off switch", it's kind of a moot point.
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Good that you admit that..."The more power you have, the less accurate you can be."...but I haven't found that quite the story. A .177/20/22/or 25 hole though the brain or heart on typical/tradtional airgun sized critters (squirrels to rabbits) seems to work just as well for me YThey either puff up or hump up, fall sideways)...might be that a larger pellet delivers more energy per inch of "meat travel", but if it doesn't smack the "off switch", it's kind of a moot point for DRN (dead right now)....might die a a couple of yards closer to the impact point, but still take a scramble.
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Good that you admit that..."The more power you have, the less accurate you can be."...but I haven't found that quite the story. A .177/20/22/or 25 hole though the brain or heart on typical/tradtional airgun sized critters (squirrels to rabbits) seems to work just as well for me...might be that a larger pellet delivers more energy per inch of "meat travel", but if it doesn't smack the "off switch", it's kind of a moot point.
Lol, I never said I wasn't accurate, but it is true about the terminal shock on typical critters. If I am off by just a little with my 50 FPE, the outcome will be the same. Not so much with a .177.
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To the best of my knowledge, the smaller .177 caliber does have one significant advantage over the..22. & .25, and that's when it comes to penetration.
With the smaller frontal surface area, the .177 can penetrate deeper than the larger caliber with less fpe. This comes in very handy when shooting at animals with skull bones that are much harder or denser than the skull of let's say a rabbit or squirrel. Takes less energy to get deep in the animals fuse box, which results in an effective kill.
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Long ago, had a Sunday school teacher who loosened up and told the story of his service in WWII (which might have been the best sunday school lessor he ever taught).
Got hit right though the chest, about 2" from cehter line, mid chest by a 20MM round that didn't detonate. He ran to the medic, who managed to save him (but not one lung and two ribs).
So I kin of started off doubting that a really big hole though something besides the immediate "off switch" was going to drop a critter. Sure, 1" closer to dead center would have done it....but that little difference (on a human scale) made all the difference between listening to him speak in 1962 and reading about him in the memorial church bulletin.
Not that I don't like big fat projectiles...I really do (as a BP shooter)....but I do realize that an ice pick in the brain works just about as well as a Crusader's broad sword.
So...my goal is to stay within the range where I'm really sure (like 97%) that I'm going to put that pellet right though the "good stuff" (heart lungs/brain)...and let the other shots pass on by.
ADDED:
How did I come to that idea?
Shotguns and upland game hunting.
Picking up birds that had just one little #7 1/2 hole though the heart, neck/spine, or the brain. Bad form, too long a distance, bad patterned...didn't matter. Had to stock-stroke other birds that were flopping around (quail/pheasant/dove) to kill them even with 5 or 6 hits through non-immediately vital areas...but others with just one little hole in the right place were DRN (dead right now).
Go ahead...think that major energy and a big pellet is going to make up for poor placement...it's not, but it may make you feel better to believe so..
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I agree you still have to hit the off switch regardless. .177. may rule to many, but I'm sticking with the .25 as my experience with it has proven to be a better critter getter.
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Old vid but there is no replacement for displacement or in our case bore size ;)
https://www.youtube.com/watch?v=DImiWYmrGsk (https://www.youtube.com/watch?v=DImiWYmrGsk)
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I agree you still have to hit the off switch regardless. .177. may rule to many, but I'm sticking with the .25 as my experience with it has proven to be a better critter getter.
Keith!! I think it is advantageous to look more into that .177 debate.. I remember 35 to 40 years ago, it was the norm to buy .177 or .22 for hunting and not only that, it was the only caliber aviable for airgun PERIOD!! I cannot tell you how many small games I bring back home with my 1322 and Slavia.. The only thing that is not NEGOCIABLE with such low power is you have to do your part .. But really, it makes you a better rifleman overall.
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I agree you still have to hit the off switch regardless. .177. may rule to many, but I'm sticking with the .25 as my experience with it has proven to be a better critter getter.
Keith!! I think it is advantageous to look more into that .177 debate.. I remember 35 to 40 years ago, it was the norm to buy .177 or .22 for hunting and not only that, it was the only caliber aviable for airgun PERIOD!! I cannot tell you how many small games I bring back home with my 1322 and Slavia.. The only thing that is not NEGOCIABLE with such low power is you have to do your part .. But really, it makes you a better rifleman overall.
Yep, I started with the .177, then .22 and now .25. All bring home the bacon when I do my part, more so with the .25, but they are not anymore dead than with the others. My point was that with the .25 accuracy is not quite as critical though you still have to hit the off switch. Somehow that got lost and became debated.
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Well precision and energy are both important but of course if no precision then power is irrelevant. I wonder why UK shoots far with 12fpe, is it because their pellets have better BC? I would assume people here are just as accurate as Europeans, right?
In the UK, airgunner without a FAC license cannot shot airguns over 12 FPE. Many shooters just skip getting FAC license and perform their pesting needs using what they already have. You can, in some part, thank them for the quality and precision you see in modern airguns.
Everything is all about precision, regardless of caliber. For me, I match the airgun and caliber and pellet to the intended target. For many folks for many years, .177 for feather, .22 for fur. .20 was a nice compromise, too. Nowadays... Larger calibers have opened up the doors- wide open!
Since the thread is all about 177 vs 22 if they're the same weight... I let my gun decide what it shoots, because I want accuracy more than I want a given weight. :)
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Thanks all for excellent explanation.
Unfortunately extra heavy .177 pellets are unstable by using standard barrels.
I am thinking that caliber .133 will be the future.
My BSA Buc loves the 15gr Sniper Magnums... I am pretty sure all BSA barrels are 1:19 twist... Pellets make their own rules as far as twist... they need very little in comparison to slugs/bullets...
then there are foster slugs that do well in the right smooth bore and they spin very slowly also...
Pellets because they come in different head shapes, waist configuration etc in the end will like what they like at different velocities...
I have bolded Interesting info.
I was thinking why larger calibers are more accurate at the same FPE .
Pellets are stabilized by the skirt and larger caliber has larger skirt.
https://www.pyramydair.com/air-gunsairsoft-schematics (https://www.pyramydair.com/air-gunsairsoft-schematics)
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Old vid but there is no replacement for displacement or in our case bore size ;)
https://www.youtube.com/watch?v=DImiWYmrGsk (https://www.youtube.com/watch?v=DImiWYmrGsk)
Great visual Matt that drives home my point I was trying to convey.
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YES but for the startle of starlings 1 FPE at 100 yard is enough.
What is your opinion on next :
“I was thinking why larger calibers are more accurate at the same FPE .
My opinion is that the pellets are stabilized mainly by the skirt and larger caliber has larger skirt."
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Problem with those vids is I'm not sure the energy level was the same. And if it wasn't, then you might reverse the results if you used a 50 foot pound .22 vs a 35 foot pound .25.
Really what got me started with the same weight, same speed tests....I just wasn't seen that kind of difference when both the .22 and the .25 were of equal energy/pellet head shape.
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There were some confusions as why this question is raised, points were made that 0.177 and 0.22 were for different purposes and the scenario is hypothetical etc.
I am thinking getting PP700 pistol. I thought I settled on the 0.22, but still I have some questions on that, thinking 0.177 may achieve the same goal and with some advantages.
Both 0.177 and 0.22 have the same everything except barrel bore size. Now we have pellets of almost the same weight for the two calibers, I thought 0.177 with a smaller head will get less air resistance (true) and more stable (may not be true based on feedback, because of longer skirt). So if I can get them to fly at the same speed (so same power) then 0.177 can fly straighter and longer and with more hitting power. And also don't forget with the smaller head it gains more penetrating power to break some hard skulls.
However it is clear now we will not get the same power with the same amount of air release - 0.22 will get more muzzle energy than 0.177 and the advantages of 0.177 in air resistance probably is not sufficient to overcome the lower initial energy, at least in the shorter and medium distances.
So I think I will still choose 0.22 for the PP700. If 0.177 has a longer barrel (30% longer than 0.22) then the initial energy will match 0.22, and 0.177 could be preferred.
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If you are just punching paper, I'd go with the .177 for more shot count per fill. If you plan on doing some pesting too, I'd go with the .22. The .22 will also be more fun on the reactive targets as well.
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Problem with those vids is I'm not sure the energy level was the same. And if it wasn't, then you might reverse the results if you used a 50 foot pound .22 vs a 35 foot pound .25.
Really what got me started with the same weight, same speed tests....I just wasn't seen that kind of difference when both the .22 and the .25 were of equal energy/pellet head shape.
I won't go at length but trying to compare a high powered .22 cal to a under powered .25 cal is moot and not the reality we live in...nor does trying to put them on equal grounds/footing with power...bigger bores have more power for a reason and that is why we utilize them in the fashion we do...
The actual kill zone due to diameter of the wound channel being much greater the bigger the bore size is, should not be dismissed...the expansion from a .25 cal pellet when compared to an expanded .22 pellet will provide an INCREDIBLY larger wound channel/kill zone...to boot I've expanded a .25 cal pellet to .4" at just a mere 25 FPE, The 'off' switch doesn't have to get hit 'hard', it just has to get hit...
Not sure why people insist on trying to compare one caliber to another...ballistics are very simple and there is a reason we use many different calibers in both air gunning and firearms....the most common small bore in firearms is .22 and those are laughed at by many hunters/firearm enthusiasts unless you're plinking cans with them ::) ....to sit around and debate which is potentially better in what scenario is more opinion than fact.
I personally have no bias towards any caliber but at the end of the day I know what each one is capable of and best suited for...
-Matt
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Don't see why...a lot of out-the-box .25 shooters are getting about 40-43 foot pounds....are other .22 PCP's that will do that out the box...so it's not really an unfair comparsion.
Don't get me wrong...I do believe in big bullets...but they need to be seriously larger to be a noticeable difference.
I can tell the critter reactions form a 25 foot pound .177 from a .25 foot pound .25. HAve a harder time telling a 25 foot pound 5mm from a 25 foot pound .22 or a .40 foot pound .22 from a 40 foot pound .25(in fact...I can't).
So the little bit of fifference in diameter really is NOT as important, at least if the energy of the pellet at impact is nearly the same.
Lets just say we disagree.....but I've come to use 24-30 foot pound .177's more and more in the last few years...because it works for me.
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If you are just punching paper, I'd go with the .177 for more shot count per fill. If you plan on doing some pesting too, I'd go with the .22. The .22 will also be more fun on the reactive targets as well.
Hunting is what is in my mind so 0.22
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If you are just punching paper, I'd go with the .177 for more shot count per fill. If you plan on doing some pesting too, I'd go with the .22. The .22 will also be more fun on the reactive targets as well.
Hunting is what is in my mind so 0.22
IMHO, that is the wiser choice. Depending on the pistols tuning flexibility, you can lower the power to extend the shot count for plinking or crank it up for good energy for hunting. IIRC, from one video I watched, you should be able to get ~20 shots around 15 FPE in .22 caliber. Probably can go higher, but I'm not familiar with the pistol to know what it can really do. I can say after watching the video, I would like to have one of those. It looks great and a lot of fun. Never had a pistol that I could air up, just co2.
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Well, if the thought is on using a PP700 pistol... Mine is a .177.
It is just under a year old and has 20-something squirrels to date, a number of sparrows, some rats, mice, a copperhead, a hundred+ pigeons, and 1 starling. It is accurate with 15 grain H&N Sniper Magnums, 13 grain Skenco New Boy pointed pellets, 11 grain BEeman Silver Arrow pointed, JSB Ultrashock hollowpoints, H&N Crow Magnums hollowpoints, JSB Exact Heavies, Crosman >anything< except Destroyers (and those even work under 15 yards), RWS Mesiterkugeln 7 grain wadcutters...
Basically, every pellet I pick up it shoot well. Out of 19 total pellets, I can use 18 of them at 20 yards with lethal accuracy (meaning inside a nickel easily). My preferred pellet is the JSB Ultrashock. Though it is not the most accurate nor the heaviest, it hits a happy medium with accuracy, energy, and speed.
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Keith, 20 shots at 15fpe is about right. Wayne has it set that way and he gets 23 shots.
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Peter, so far I have heard consistently that SPA guns are not pellet picky. So I believe this is true for .22 as well. I was assessing which one is more energy efficient. From the discussions it appears that .22 will be more efficient.
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Peter, so far I have heard consistently that SPA guns are not pellet picky. So I believe this is true for .22 as well. I was assessing which one is more energy efficient. From the discussions it appears that .22 will be more efficient.
Yup. Pretty typical in PCPs for the .22 to have that edge.
I picked .177 for mine because- among other things- I knew I would be less tempted to take longer shots on vermin. Once I got mine and discovered just how accurate it was, I went ahead and gave in to temptation with excellent results.
I've been saying since I bought mine last October it's the best money in a PCP one can spend; nothing touches it at 2 times the cost once you factor in everything it comes with. Adjustable everything, great accuracy, and nonsensitivity to pellet choices. At the time I was leaning strongly toward a PRod... I made a spreadsheet with every PCP (rifle and pistol) I could find, then started adding points for features I wanted and were practical. This came out on top.
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Peter, so far I have heard consistently that SPA guns are not pellet picky. So I believe this is true for .22 as well. I was assessing which one is more energy efficient. From the discussions it appears that .22 will be more efficient.
Yup. Pretty typical in PCPs for the .22 to have that edge.
I picked .177 for mine because- among other things- I knew I would be less tempted to take longer shots on vermin. Once I got mine and discovered just how accurate it was, I went ahead and gave in to temptation with excellent results.
I've been saying since I bought mine last October it's the best money in a PCP one can spend; nothing touches it at 2 times the cost once you factor in everything it comes with. Adjustable everything, great accuracy, and nonsensitivity to pellet choices. At the time I was leaning strongly toward a PRod... I made a spreadsheet with every PCP (rifle and pistol) I could find, then started adding points for features I wanted and were practical. This came out on top.
I went through struggles as well, especially when the Prod was on sale this summer for sub $300. Prod is famous for its quietness. It also comes with stock for carbine conversion. For PP700 I will have to get a suppressor to use at home. The advantage is that the PP700 has a regulator, although it does not work as well.
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What about to start different question.
Accuracy and loudness .177 vs .22 bullets, if the same weight at 900 FPS
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Realistically, WHO CARES how a .177 compares to a .22 if the pellet or bullet weight and velocity is the same?.... One of the two, if not both, will be shooting with pellets/bullets so far from the optimum for that gun and caliber you are artificially skewing the results.... The .177 could probably perform better with a lighter pellet/bullet, and almost certainly the .22 cal would perform better with a heavier one.... and if allowed to do so, will surpass the .177 in FPE, but will use more air doing it....
Set up each caliber for it's optimum performance, regardless of the pellet/bullet weight required.... The .177 will be better for some jobs, and the .22 for others.... If you don't need high FPE, and want more shots, use the .177.... If you need the extra power, use the .22.... Why operate with one hand tied behind your back?.... I don't see the point.... JMO....
Bob
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YES Bob , you have true for sure . I had been interesting just theoretically.
YES but for the startle of starlings 1 FPE at 100 yard is enough.
What is your opinion on next :
“I was thinking why larger calibers are more accurate at the same FPE .
My opinion is that the pellets are stabilized mainly by the skirt and larger caliber has larger skirt."
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Greg, I have the .22 PP700 (the Gen I version from MrodAir) and it is as forgiving on pellet selection as everyone says. It is a great shooter for sure, and I highly recommend it.
I bought mine mostly for paper punching, and went with the .22 for two reasons - I already had a huge stash of .22 pellets with lots of different types to try, and for single shot loading I simply prefer the larger .22 cal pellets. Those .177 are getting hard to see without cheaters anymore!
Now than you have declared that you want this pistol, I'd say the whole "which is better" thing is a moot point. Unless you plan to build the pistol into a carbine, I doubt you will be using it for pesting or hunting out past 50 yards. The gun is probably accurate enough, but most pistol sized sights are not going to support that, and there are much better options for that task.
So get whichever you prefer. The real difference is that .22 will cost more per pellet than .177 (but not that much more) and you can tune for a few more shots at a reasonable velocity with a .177 (but not that many more).
I have mine set up to shoot at ~11 FPE and I get ~40 shots at under 2.5% ES. I am very happy with the gun, the shot string, and the accuracy. I wish it was a bit quieter, but the gun sure is nice.
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Peter, so far I have heard consistently that SPA guns are not pellet picky. So I believe this is true for .22 as well. I was assessing which one is more energy efficient. From the discussions it appears that .22 will be more efficient.
Yup. Pretty typical in PCPs for the .22 to have that edge.
I picked .177 for mine because- among other things- I knew I would be less tempted to take longer shots on vermin. Once I got mine and discovered just how accurate it was, I went ahead and gave in to temptation with excellent results.
I've been saying since I bought mine last October it's the best money in a PCP one can spend; nothing touches it at 2 times the cost once you factor in everything it comes with. Adjustable everything, great accuracy, and nonsensitivity to pellet choices. At the time I was leaning strongly toward a PRod... I made a spreadsheet with every PCP (rifle and pistol) I could find, then started adding points for features I wanted and were practical. This came out on top.
I went through struggles as well, especially when the Prod was on sale this summer for sub $300. Prod is famous for its quietness. It also comes with stock for carbine conversion. For PP700 I will have to get a suppressor to use at home. The advantage is that the PP700 has a regulator, although it does not work as well.
Actually, noise level and the carbine stock were non-issues in my list. I was looking for adjustability and size (a true pistol) once I confirmed I wanted a pistol. Plus I had a whole bunch of .177 caliber pellets already. Since it is backyard shooting mostly, the PP700 in .177 made perfect sense. I haven't had problems with my regulator as long as I don't crank it up for max power. Shot count is 40+ as Alan describes, and accuracy still blows me away. I have can go from my lightest pellets to more than double, every imaginable pellet shape, and still just shift my aim or adjust my reticle and hit the spot I want all day long at 15, 20, 30, and even 40 yards. Using a pistol with one bag and a crummy 3-9x32 Optimus rifle scope. At some point, I'd like to get the .22 as they're just easier to handle for my fingers.
To build on what Alan says, it could probably do fine at 50 yards, but realistically, if you intend to hunt small game or shoot vermin at that range, there are better tools for the money- the PR900W comes to mind, but even the PRod would be better on account of the ease with which you can add the Crosman 1399 carbine stock.
Now for what it is worth, I have shot a goodly number of pellets through mine (around 6000?) and have had multiple days where I refilled it in one shooting session. On 2 of those occasions, I refilled using my Benjamin handpump 14 times. LOL, those last couple times my groups started growing as it was hard holding the gun steady ::)
Alan- David (Rocker1) makes a very slick carbon fiber LDC for the PP700. I highly recommend it. Taking the crack out even at 12 FPE energy levels makes for a more pleasant day of shooting.
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Greg, I have the .22 PP700 (the Gen I version from MrodAir) and it is as forgiving on pellet selection as everyone says. It is a great shooter for sure, and I highly recommend it.
I bought mine mostly for paper punching, and went with the .22 for two reasons - I already had a huge stash of .22 pellets with lots of different types to try, and for single shot loading I simply prefer the larger .22 cal pellets. Those .177 are getting hard to see without cheaters anymore!
Now than you have declared that you want this pistol, I'd say the whole "which is better" thing is a moot point. Unless you plan to build the pistol into a carbine, I doubt you will be using it for pesting or hunting out past 50 yards. The gun is probably accurate enough, but most pistol sized sights are not going to support that, and there are much better options for that task.
So get whichever you prefer. The real difference is that .22 will cost more per pellet than .177 (but not that much more) and you can tune for a few more shots at a reasonable velocity with a .177 (but not that many more).
I have mine set up to shoot at ~11 FPE and I get ~40 shots at under 2.5% ES. I am very happy with the gun, the shot string, and the accuracy. I wish it was a bit quieter, but the gun sure is nice.
Thanks Alan.I used to be in Michigan.
I got lots 0.177 and 0.22 pellets, mostly cheap stuff for plinking. I will use the pistol for hunting so likely I will get higher quality ammo for that.
At home I plinking with break barrels to get some exercise, and the challenge (frustration).
40 shots at 11fpe is pretty efficient. I think if you bump to 16fpe you will get about 23 shots
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Peter, so far I have heard consistently that SPA guns are not pellet picky. So I believe this is true for .22 as well. I was assessing which one is more energy efficient. From the discussions it appears that .22 will be more efficient.
Yup. Pretty typical in PCPs for the .22 to have that edge.
I picked .177 for mine because- among other things- I knew I would be less tempted to take longer shots on vermin. Once I got mine and discovered just how accurate it was, I went ahead and gave in to temptation with excellent results.
I've been saying since I bought mine last October it's the best money in a PCP one can spend; nothing touches it at 2 times the cost once you factor in everything it comes with. Adjustable everything, great accuracy, and nonsensitivity to pellet choices. At the time I was leaning strongly toward a PRod... I made a spreadsheet with every PCP (rifle and pistol) I could find, then started adding points for features I wanted and were practical. This came out on top.
I went through struggles as well, especially when the Prod was on sale this summer for sub $300. Prod is famous for its quietness. It also comes with stock for carbine conversion. For PP700 I will have to get a suppressor to use at home. The advantage is that the PP700 has a regulator, although it does not work as well.
Actually, noise level and the carbine stock were non-issues in my list. I was looking for adjustability and size (a true pistol) once I confirmed I wanted a pistol. Plus I had a whole bunch of .177 caliber pellets already. Since it is backyard shooting mostly, the PP700 in .177 made perfect sense. I haven't had problems with my regulator as long as I don't crank it up for max power. Shot count is 40+ as Alan describes, and accuracy still blows me away. I have can go from my lightest pellets to more than double, every imaginable pellet shape, and still just shift my aim or adjust my reticle and hit the spot I want all day long at 15, 20, 30, and even 40 yards. Using a pistol with one bag and a crummy 3-9x32 Optimus rifle scope. At some point, I'd like to get the .22 as they're just easier to handle for my fingers.
To build on what Alan says, it could probably do fine at 50 yards, but realistically, if you intend to hunt small game or shoot vermin at that range, there are better tools for the money- the PR900W comes to mind, but even the PRod would be better on account of the ease with which you can add the Crosman 1399 carbine stock.
Now for what it is worth, I have shot a goodly number of pellets through mine (around 6000?) and have had multiple days where I refilled it in one shooting session. On 2 of those occasions, I refilled using my Benjamin handpump 14 times. LOL, those last couple times my groups started growing as it was hard holding the gun steady ::)
Alan- David (Rocker1) makes a very slick carbon fiber LDC for the PP700. I highly recommend it. Taking the crack out even at 12 FPE energy levels makes for a more pleasant day of shooting.
Peter, my scenario is somewhat different as I am looking to use it more for hunting.
Since I already have a AT44Q10 0.25 which is very accurate, I will use that for larger or far away targets. I like to have a pistol with me as a backup and also to take care smaller targets in shorter range. How short will depend on how well I can handle it and how accurate the gun is. I have seen videos people gets hogs with 20fpe .22 so if I can crack the power to 16-20fpe I think the pistol can take care a lot of stuff, and I may even just carry the pistol to lighten the load!
I have a compressor so hopefully I will not get into physical exhaustive situation like you did.
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Finally I have ordered the 0.22 caliber PP700 pistol! Thanks all for the discussion.
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Hope you have as much fun and use from it as I've had....really has been an amazing value.
Will take another bite of the dark-side same-weight-different-caliber cookie.
Lets say you have two different PCP rifles. Either on can launce 16ish grain pellets to 920fps. One is a .177 (16.2gr. JSB's) and the other a .22 (15.9-16gr. JSB's)...oot exact matching weights, but close enough.
So they both start off with about 30-31 foot pounds at the muzzle.
Actually turns out that the BC's are not all that far apart....agree that they should be, but real world testing/published figures don't show a whole lot of difference.
(Am tired of harping on this song....but while you would think BC was kind of fixed in stone....it's not. One rifle/barrel will often earn more or less than the next one. Likely depends on various extra motions the pellet picks up (nutation/precession mostly) and how chewed up by rifling the expised outwer most edges).
So take published BC numbers with a grain-of-salt...were likely true for that rifle/taht barrel, but may not be true for your rifle. your barrel.
What I can tell you is that it has always taken more air per shot to get the same weight in a smaller bore up to the speed of the same weight in a larger bore.
LArger bore has the advatage of more pellet base area to push on (it's that "per square inch" thing that is part of PSI).
So with a small bore we can't increase pressure past the rifle'sw max....so we can't increase the push on the base of a smaller diameter pellet,,...so all we can do is push LONGER (eject more air so the push is maintined longer).
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So with a small bore we can't increase pressure past the rifle'sw max....so we can't increase the push on the base of a smaller diameter pellet,,...so all we can do is push LONGER (eject more air so the push is maintined longer).
Yep, until the valve is open when the pellet exits, which is then the maximum FPE for that pellet / barrel / pressure / port size combination....
Bob
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I wonder why the BC for .177 is not much better than the.22 given the theoretical possibilities. Is that the designers did not push enough research?
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Not sure I understand your statement.... The SD and therefore the BC for similar pellet shapes are proportional to the caliber.... ie .25 > .22 > .20 > .177....
It is only when you use extra heavy pellets in .177 and extra light ones in .22 that the SD and BC favours the smaller caliber.... This trend applies to all guns, both air and PB.... Bigger bullets carry further.... hence the reason for 16-18" Naval guns.... and why the Sniper's weapon of choice is the .50 BMG round....
Bob
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So with a small bore we can't increase pressure past the rifle'sw max....so we can't increase the push on the base of a smaller diameter pellet,,...so all we can do is push LONGER (eject more air so the push is maintined longer).
Yep, until the valve is open when the pellet exits, which is then the maximum FPE for that pellet / barrel / pressure / port size combination....
Bob
If I understand right disadvantage of higher pressure and more air necessity for smaller calibers can be reduce by longer barrel.
Unfortunately too long barrel have to be also ticker or tensioned for good accuracy .
How long are barrels and shrouds at Gauntlet and SPA/Artemis M22 ?
Peter
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Not sure I understand your statement.... The SD and therefore the BC for similar pellet shapes are proportional to the caliber.... ie .25 > .22 > .20 > .177....
It is only when you use extra heavy pellets in .177 and extra light ones in .22 that the SD and BC favours the smaller caliber.... This trend applies to all guns, both air and PB.... Bigger bullets carry further.... hence the reason for 16-18" Naval guns.... and why the Sniper's weapon of choice is the .50 BMG round....
Bob
I am referring to the equal weights situation you did the calculation earlier
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I see little point in "pushing research" on pellets for such an unusual situation where the larger caliber is being handicapped by the question proposed.... It would appear pellet manufacturers have the same opinion.... although heavier pellets are becoming available in all calibers as PCPs become more powerful.... For the ultimate in performance with high SD projectiles, you need to look at bullets instead of pellets....
Bob
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Not sure I understand your statement.... The SD and therefore the BC for similar pellet shapes are proportional to the caliber.... ie .25 > .22 > .20 > .177....
It is only when you use extra heavy pellets in .177 and extra light ones in .22 that the SD and BC favours the smaller caliber.... This trend applies to all guns, both air and PB.... Bigger bullets carry further.... hence the reason for 16-18" Naval guns.... and why the Sniper's weapon of choice is the .50 BMG round....
Bob
I am referring to the equal weights situation you did the calculation earlier
in equal weights, this will end up skewing things automatically in favor of the smaller caliber. The only time I would really recommend going with a smaller caliber at a heavier weight is when limited by caliber size (such as folks in Illinois deal with) or when there's a gun pointedly favors heavy pellets such as the Sumatra or some of the SPA models.
An argument can be made for when penetration is paramount, but given how lower energy levels can still pass through prey, I personally go for a larger caliber with the most accurate pellet, even if it is slower, because a pass-through means I have to worry about what is behind the prey. Hunters and those who are pesting on wide-open spaces may not have such concerns, so in those, everything should be dictated by "most accurate" and nothing else.
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Thanks Bob and Peter. Since I already ordered the 22 version, so my question now is which would be a better hunting pellet for hunting? I saw several posts advocating polymags.
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Whatever is the most accurate in your gun....
Bob
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Thanks Bob and Peter. Since I already ordered the 22 version, so my question now is which would be a better hunting pellet for hunting? I saw several posts advocating polymags.
Polymags are good, but what Bob said should be Gospel- whatever is most accurate.
If your ranges are short (and this is a pistol so I would think so) then anything you can shoot dime-size groups at the desired distance will be accurate enough for clean kills. Although Beeman Silver Arrows are notably the most accurate in mine PP700, I have a nice assortment of others that group well enough out to 30 yards that can be used, so I trend toward JSB Ultrashocks on birds and mice. On squirrels, Skenco New Boys and Skenco Ultra Shocks, JSB Exact Heavies and Ultrashocks, H&N Sniper Mags and Barracudas, and Beeman Silver Arrows. The list is actually larger, but those are what I've used thus far. If you end up having Polymags group very well, they produce great results, and FWIW, my guns that Polymags work in also do well with Gamo Redfires, which can be bought at WalMart (though they are kinda pricey for what you get).
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Thanks Bob and Peter again.
I only have CPHP and Ruger from Walmart so I will need to order a few more to try out. I saw red fire and red rockets by Gamo in Walmart.
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I've found my Varmint likes those Ruger point pellets. They're somewhere between true point and domes. Hopefully your pistol treats them the same way my Varmint does. That they weigh 17 grains and are a little softer than the Crosmans is a plus IMO.
I'd avoid the Gamo Rockets- never had good luck with those in anything. Maybe one of the other folks with a PP700 can chime in.
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Do known that in the one rifle I could find that shot the 21gr. Piledrivers well, the BC was really high (from my testing and from Harry's tests). In the rifles that didn't shoot them well (with signs of tipping/key holing) the BC wasn't all that (like 1/3 as high).
So evidently, it does make a difference if the pellet wanders around with some yaw and wobble (nutation/pression) on the way to the target (or to the chronograph for BC tests).
Don't think it's that the small caliber pellet makers haven't tried for some long/heavy/high BC pellets....but past some point, are up against the limits of the typical .177 barrel's twist.
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Also, after some point, the SD is too high, and you can't get a decent velocity without excessive barrel length and/or pressure....
Bob
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We take a kind of reverse coruse here....if you've got a bit of an air hog PCP (reguardless of caliber), then feed it the heavest weight pellets it will shoot well. Will often earn enough energy over the same shot count to be classed as "OK" efficient (won't be as fast...but working out the energy, is very likely to earn more foot pounds for the same number og "good" shots).
IF you do manage to get a PCP shooting with more energy with lite pellets (which can be done, but it isn't real common without some extensive mods)....then shoot the lite pellets.
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Thanks Peter for the pellets info. Hopefully mine will not be picky just like yours