GTA
All Springer/NP/PCP Air Gun Discussion General => European/Asian Air Gun Gates => German AirGun Gate => Topic started by: Bill_in_TR on December 04, 2017, 12:35:07 PM
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I was watching a video recently of someone shooting a Diana 48 sidelever. As I watched him cock the gun it didn't look to me like he was putting a lot of effort into it at all. I know that at my age and condition I am probably nowhere near as strong as the guy in the video. But even so his effort doesn't look like much at all. Is this because it is a side lever? Do they provide a leverage advantage I am not aware of?
I am currently shooting my tuned D34 (14.5 fpe) a lot and it really gives me a workout. I have an R7/HW30 on my wish list for some lighter effort shooting. But if a side lever is some how easier to cock It would be something to consider down the road. I believe he was shooting a stock D48 but I could be wrong. But it would be nice to get more fpe with less effort.
Or was I just hallucinating as I watched the video?
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Bill, 'Hard to beat an r7/hw 30 for pure fun/ accuracy, but a fwb 300s or mini will blow you away w/ accuracy & you can cock it w/one finger.g
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I have a 48 and a 34. I am a 71 year old male in good health and probably average or better physical shape for my age.
That said, I really enjoy the extra power of the 48 though it is decidedly harder to cock than the 34. Of course the technique is a bit different as well as the lever is on the side. It takes getting used to.
My 48 was quite difficult to cock when new but after a couple hundred rounds it did loosen up a bit. It is still noticeably harder to cock than the 34. Unless you go with a lighter spring it is probably not the kind or rifle you want to shoot off the bench all day.
I have found shooting it off the bench I can shoot it as accurately as my TX 200. I think I'd like to try a 460 next but that may wait awhile.
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I'm 46 and have had my 48 for about 18 years now. Even in my 30's, it was a bit of an effort to cock (thank goodness for the anti-bear trap design). At 5'6" and just under 150lb, I am on the strong side, but not exactly Hercules by any means. The 48 certainly provides a good workout for my back muscles ;)
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Here we go again...
At 72 I am in terrible shape.
High Blood Pressure
High Cholesterol
Type II Diabetes
80 pounds overweight
(All attributed to a highly toxic de-foliant used by our good uncle in Southeast Asia because of which I receive another monthly check from the afore-mentioned uncle.
That being said I have been struggling for about 6 months now trying to get the Diana 52 (The stock is a bit better looking and one inch longer than the 48) to shoot straight.
I think it is the scope.
I shot the rifle about 330 times yesterday at the range and in the yard.
There is a technique I use as most of my shooting with the 52 is from a seated position (off of the buckets).
I hold the rifle vertically on my right thigh and grasping the forearm with my left hand and then I push the cocking arm away from the action with my right hand.This leaves the action open directly in front of my face where I can inspect the chamber while inserting the pellet. The aforementioned left hand is correctly positioned to press on the anti-bear trap device allowing the cocking arm to return to battery.
Off the bags, such as off the bench, I find the cocking action to be not normal.
My other springers (see signature) are easily cocked and, no I do not slap the barrel when cocking the HW35 or R1.
I had a 48 and the accuracy was fine but the stock was a might short for my 6’ 3” frame.
The 52 is perfect, IMHO, if not a pound or two heavy.
The weight does make carrying the of my powder burning arms a bit easier especially at 7000 feet in the Wyoming Rockies.
Stay safe
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My routine for cocking my 48 is the same as Frank's. It's the easiest cocking gun I own.
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I have a 48 & 54 sidelever and much prefer an underlever when it comes to cocking. For me, an underlever isn't nearly as awkward to manipulate when cocking. I would like to handle a 460 and get a feel for how it cocks. The 54 is almost new, maybe a hundred rounds downrange, and it really takes some effort to cock, especially at the end of stroke. I have two Gamo Accu underlevers (.177 & .22). Though not as powerful and far reaching as the Diana's, they are just as accurate and smooth cocking at 27lbs.
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It seems that the consensus is that the D48 is harder to cock than my D34 so that is not what I would be looking for. I have to wonder how the guy in that video made it look so easy.
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Duplicate
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I have a 48 & 54 sidelever and much prefer an underlever when it comes to cocking. For me, an underlever isn't nearly as awkward to manipulate when cocking. I would like to handle a 460 and get a feel for how it cocks. The 54 is almost new, maybe a hundred rounds downrange, and it really takes some effort to cock, especially at the end of stroke. I have two Gamo Accu underlevers (.177 & .22). Though not as powerful and far reaching as the Diana's, they are just as accurate and smooth cocking at 27lbs.
I agree with you Dick.
For extended shooting: 400-500 pellets a day, you can’t beat an under lever.
My TX, tuned by the Great One (Motörhead) has no twang with a trigger that breaks like glass shooting 8.64gr FTT at 917fps.
Deadly accurate.
More so in someone else’s hands. ;)
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I was watching a video recently of someone shooting a Diana 48 sidelever. As I watched him cock the gun it didn't look to me like he was putting a lot of effort into it at all. I know that at my age and condition I am probably nowhere near as strong as the guy in the video. But even so his effort doesn't look like much at all. Is this because it is a side lever? Do they provide a leverage advantage I am not aware of?
I am currently shooting my tuned D34 (14.5 fpe) a lot and it really gives me a workout. I have an R7/HW30 on my wish list for some lighter effort shooting. But if a side lever is some how easier to cock It would be something to consider down the road. I believe he was shooting a stock D48 but I could be wrong. But it would be nice to get more fpe with less effort.
Or was I just hallucinating as I watched the video?
Beyond the realm of the subjective:
The usual 48-52-54 will take about 40# of peak cocking force to complete the cycle, the 34 will take about 35# of peak cocking force to complete the cycle.
Smartly modified 48-52-54's can yield between 15 and 16 ft-lbs ME with peak cocking forces of around 22-24# and no, it is not just the spring.
As long as you do not want 18-22 ft-lbs of output, peak cocking forces can be managed to whatever YOU need.
Telling you how many times I can cock my guns is very subjective and mostly depends on technique, not force.
As an FT shooter, I sometimes go through a half tin of pellets in a match day.
If you are interested, drop me a line.
HM
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Hector, the numbers you have given are in line with what I would expect for those guns. And they agree with the numbers given in the specs on the Pyramid Air and other sites for those guns.
I did a pretty careful job of tuning my D34 and using a GSX-OS kit from Air Rifle Headquarters I am reasonably happy with my results. The cocking and shot cycles are much smoother and quieter. But the fpe only dropped about a pound to about 14.5. The cocking effort did not improved much at all.
I don't need high velocity or high fpe for my shooting. So my current plan is to get an R7/HW30S for a more effortless shooting session. The D48 video got me interested because of the apparent light effort shown in that video. I thought a fixed barrel gun might provide some improved accuracy, although my D34 gives me some pretty good groups. But I want something with a lighter cocking effort than my D34. I also actually liked the idea of the bigger heavier gun that the D48 is.
I guess for now I will stick to my plan of acquiring an R7/HW30S.
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Bill
FWIW: I have a couple of HW30's and a R7. Straight out of the box they are excellent little guns, no doubt. Having said that, I detuned the R7, for what started out to be as strictly a target setup. Over time it eventually developed into doing double duty on occasion as a very accurate squirrel sniper.
I put a chopped down Vortek spring and VAC mainseal, drink bottle piston sleeve, Ultimox lube job. The gun is crazy quiet, smooth, easy to cock, and shoots sub-600 fps in the 5.75 FPE range at the muzzle. Is remarkably accurate out to 40+ yards. And is more than capable of taking squirrels and birds at 30-35 yds. I have several threads about its performance on squirrels over on the hunting gate, if you want to search "HW30/R7" they should pop up. If hunting is not your thing, no problem, its not for everybody.
Given a choice, if they are comparable in price. I'd get another R7 over the HW30. The stock is a little slimmer, feels more refined, and has checkering. The gold anodized trigger and set screw also give it a more refined appearance. IMO! ;D
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Harpoon1,
There is an HW30S on AoA that has a walnut stained beech stock with checkering that looks absolutely gorgeous in their pictures. But when the budget is ready I will look carefully at both the R7 and HW30S and decide.
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Harpoon1,
There is an HW30S on AoA that has a walnut stained beech stock with checkering that looks absolutely gorgeous in their pictures. But when the budget is ready I will look carefully at both the R7 and HW30S and decide.
Yep, thats the "Deluxe" version, has a shorter fore end and fully exposed breech block. I personally prefer the longer fore end of the R7 and "regular" HW30 but, "to each his own"! They all shoot the same, its just a matter of aesthetics.
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Hector, the numbers you have given are in line with what I would expect for those guns. And they agree with the numbers given in the specs on the Pyramid Air and other sites for those guns.
I did a pretty careful job of tuning my D34 and using a GSX-OS kit from Air Rifle Headquarters I am reasonably happy with my results. The cocking and shot cycles are much smoother and quieter. But the fpe only dropped about a pound to about 14.5. The cocking effort did not improved much at all.
I don't need high velocity or high fpe for my shooting. So my current plan is to get an R7/HW30S for a more effortless shooting session. The D48 video got me interested because of the apparent light effort shown in that video. I thought a fixed barrel gun might provide some improved accuracy, although my D34 gives me some pretty good groups. But I want something with a lighter cocking effort than my D34. I also actually liked the idea of the bigger heavier gun that the D48 is.
I guess for now I will stick to my plan of acquiring an R7/HW30S.
Bill;
Your OP was about cocking effort and if the sidelevers had an advantage. Perhaps I was not clear enough:
The sidelevers CAN be MADE to have an advantage the break barrels cannot dream of.
Consider that in a 12 ft-lbs output machine based on the 48 general pattern, you are "investing" 22 lbs of peak cocking force. That is 0.54 ft-lbs of output per lb of peak cocking force
The R-7 architecture will give you 7½ ft-lbs output for 18 lbs of cocking force, that is 0.4 ft-lbs of output per lb of peak cocking force.
In case you think that this is a small difference, ask yourself: ¿would I rather drive a car that yields 25 mpg or one that yields 32?
Yes the R-7 can be further detuned and the lightness may be what you want if you shoot a lot from the standing, kneeling, or other field positions, or if you do any walking with the gun, but if you want stability and accuracy over extended shooting sessions, then there is absolutely no contest.
And these are just the facts.
HM
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Hector
In your opinion, whats the lowest minimum FPE output for the 48/52 platform in .177 before you need to think about short stroking it?
Thanks
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Hector
In your opinion, whats the lowest minimum FPE output for the 48/52 platform in .177 before you need to think about short stroking it?
Thanks
Skimpy;
I would say that anything under 14 ft-lbs needs to be short-stroked. The few samples I have tried of 48-54's with "12 ft-lbs springs" have had very "Mushy" shot cycles. A possibility in BR, but not under field conditions. SO, IMHO, the minimum is about 14 ft-lbs with a thinner spring that still uses the full OD of the piston.
Then you find an intermediate area, where short stroked pistons can yield up to 16 ft-lbs with minimal cocking effort.
https://www.ctcustomairguns.com/hectors-airgun-blog/the-wide-and-wonderful-range-of-a-short-stroked-d-54 (https://www.ctcustomairguns.com/hectors-airgun-blog/the-wide-and-wonderful-range-of-a-short-stroked-d-54)
What applies to the 54 also applies to the 48, 52 and 56.
In fact it is the shortstroking itself what allows the very drastic reduction in cocking effort by changing the fulcrum point of the lever.
The Brits are fans of the "Skinny" piston concept (sleeving the compression chambers down to 18-20 mm's and using skirtless ultra-light pistons). And for THEM that works dandy because the highest elevation difference between medium cities is about 500 feet in altitude.
We may shoot one day at 150 FASL, and the next one at 7,500 FASL. Under these conditions, the "Skinny Piston" does not work.
Keep well and shoot straight!
HM
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Hector
In your opinion, whats the lowest minimum FPE output for the 48/52 platform in .177 before you need to think about short stroking it?
Thanks
Skimpy;
I would say that anything under 14 ft-lbs needs to be short-stroked. The few samples I have tried of 48-54's with "12 ft-lbs springs" have had very "Mushy" shot cycles. A possibility in BR, but not under field conditions. SO, IMHO, the minimum is about 14 ft-lbs with a thinner spring that still uses the full OD of the piston.
Then you find an intermediate area, where short stroked pistons can yield up to 16 ft-lbs with minimal cocking effort.
https://www.ctcustomairguns.com/hectors-airgun-blog/the-wide-and-wonderful-range-of-a-short-stroked-d-54 (https://www.ctcustomairguns.com/hectors-airgun-blog/the-wide-and-wonderful-range-of-a-short-stroked-d-54)
What applies to the 54 also applies to the 48, 52 and 56.
In fact it is the shortstroking itself what allows the very drastic reduction in cocking effort by changing the fulcrum point of the lever.
The Brits are fans of the "Skinny" piston concept (sleeving the compression chambers down to 18-20 mm's and using skirtless ultra-light pistons). And for THEM that works dandy because the highest elevation difference between medium cities is about 500 feet in altitude.
We may shoot one day at 150 FASL, and the next one at 7,500 FASL. Under these conditions, the "Skinny Piston" does not work.
Keep well and shoot straight!
HM
Hector,
Thats good intel, thanks.
Would it be possible to give us some/any details on how you go about "tuning for optimal stability" ? ;D
Thanks again.
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Hector,
Very interesting comments. I am not familiar with the notion of "short stroking" or "skinny pistons". Is there a thread or article somewhere that describes how it is done? How does a skinny piston get involved in short stroking? Skinny and short don't seem to be directly related terms. I would seriously like to understand more about these spring pistons. If I can use a D48 platform to achieve the level of cocking effort I want and also provide an accuracy potential that I like that would be great.
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Hector,
Thats good intel, thanks.
Would it be possible to give us some/any details on how you go about "tuning for optimal stability" ? ;D
Thanks again.
Tuning for Optimal stability implies shooting a lot with the gun and defining what is the best pellet for the rifle and at which velocities. It also starts from the premise that you are capable of making your gun shoot to any MV with a standard deviation of 4 fps or less in a 20 shot string.
In some rifles you will find that the pellet that shoots excellently at 800 fps will not shoot as well at 900 fps or, viceversa.
So, all tuning should start with a good knowledge of the specific gun and its likes/dislikes.
Then, from all the possible MV's you need to establish at which MV the pellets are most stable, that means that they will "go to sleep" while rotating as exactly as possible on its axis without any extraneous motions (Nutation, Precession nor Yaw). You can do this in two ways:
1.- Shoot at long range (55 yards) at rice paper squares (rice paper is the paper that is used to roll cigarrettes), analyze the tears in the paper and see which tears are more evident than others, note the MV at which those pellets were shot (usually it takes at least 5 shots at each MV)
2.- Get a laser flashlight and locate it near the muzzle pointing at the target. Shoot and observe the pellet's path (not as difficult as it sounds with a good quality scope focused to the mid-point of the trajectory). Choose the MV that yields the smallest corkscrews. If you find an MV that shows ABSOLUTELY no corkscrew at all, congrats! you have a fine barrel in your hand! It is not as common as you would think.
You could also get a high speed camera, but that would be more expensive than the laser flashlight.
Now set the gun to that MV and tune the harmonics out of the muzzle jump using whatever harmonics tuner you have.
Once you have done that, you have tuned for "Optimal Stability".
Hope this explains the process in general terms.
HM
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Hector,
Very interesting comments. I am not familiar with the notion of "short stroking" or "skinny pistons". Is there a thread or article somewhere that describes how it is done? How does a skinny piston get involved in short stroking? Skinny and short don't seem to be directly related terms. I would seriously like to understand more about these spring pistons. If I can use a D48 platform to achieve the level of cocking effort I want and also provide an accuracy potential that I like that would be great.
Short stroking and sleeving (skinny pistons) are mutually exclusive. You either use one or the other.
Short stroking is when a piston's stem is made longer than normal so that the stroke of the gun will be shorter than normal.
Some people like to use the OEM pistons and just alter the stem length, I prefer to make my pistons from scratch:
(http://imagizer.imageshack.us/v2/800x600q90/924/htD9Zj.jpg)
From left to right: Diana 48-54 T-01 trigger Full Power (FP) and Sub-12 ft-lbs (WFTF), Diana 48-54 T-05 Trigger FP and WFTF, Diana 48-56 T-06 Trigger FP and WFTF, Diana 430 FP
Short stroking has a number of advantages:
Quicker shot cycle
Less stress in the spring
Reduced cocking force (what started this thread)
Less wear on the compression chamber
It DOES need a re-inforced steel breach seal because the compression cycle is so fast that the temps reached at the seal can easily "flame cut" the seal.
On the other end of the spectrum, there is the skinny, skirtless piston:
(http://imagizer.imageshack.us/v2/800x600q90/924/CxYIFr.jpg)
That relies on a reduced diameter piston (22 mm's in this photo) at full stroke to reach the needed swept volume. A smaller piston is also a lighter piston, so lighter springs can be used to achieve the same power.
Usually this also needs altering the transfer port in the compression cylinder.
BOTH methods work well when all the factors are properly balanced. IMHO, the disadvantage of the skinny piston method is the need to restrict the use of the rifle to a relatively narrow set of conditions, of which atmospheric pressure is the main restriction, derived from altitude changes.
Because of this most of my target gun developments have folllowed the short stroking methodology.
Shooting ½"groups at 30 yards from the sitting position is quite possible with all my WFTF FT guns, and they require only 22# of cocking force. Groups at 55 yards usually hover around the 1" and sometimes, when I read the wind well, 3/4".
Hope this clarifies the ideas.
Keep well and shoot straight!
HM
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Hector,
Thats good intel, thanks.
Would it be possible to give us some/any details on how you go about "tuning for optimal stability" ? ;D
Thanks again.
Tuning for Optimal stability implies shooting a lot with the gun and defining what is the best pellet for the rifle and at which velocities. It also starts from the premise that you are capable of making your gun shoot to any MV with a standard deviation of 4 fps or less in a 20 shot string.
In some rifles you will find that the pellet that shoots excellently at 800 fps will not shoot as well at 900 fps or, viceversa.
So, all tuning should start with a good knowledge of the specific gun and its likes/dislikes.
Then, from all the possible MV's you need to establish at which MV the pellets are most stable, that means that they will "go to sleep" while rotating as exactly as possible on its axis without any extraneous motions (Nutation, Precession nor Yaw). You can do this in two ways:
1.- Shoot at long range (55 yards) at rice paper squares (rice paper is the paper that is used to roll cigarrettes), analyze the tears in the paper and see which tears are more evident than others, note the MV at which those pellets were shot (usually it takes at least 5 shots at each MV)
2.- Get a laser flashlight and locate it near the muzzle pointing at the target. Shoot and observe the pellet's path (not as difficult as it sounds with a good quality scope focused to the mid-point of the trajectory). Choose the MV that yields the smallest corkscrews. If you find an MV that shows ABSOLUTELY no corkscrew at all, congrats! you have a fine barrel in your hand! It is not as common as you would think.
You could also get a high speed camera, but that would be more expensive than the laser flashlight.
Now set the gun to that MV and tune the harmonics out of the muzzle jump using whatever harmonics tuner you have.
Once you have done that, you have tuned for "Optimal Stability".
Hope this explains the process in general terms.
HM
Hector
With the right lighting, I've noticed the occasional corkscrewing. It's been so random, I always wrote it off as just an irregular pellet. I also like the "reading the paper tears" idea. I used that often years ago when "tunning" a particular bow and arrow combination. Never thought about using it for checking pellet stability
Good stuff!
Thanks for the thoughtful, in depth reply. It was very helpful.
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my 52 and 54 are not as difficult to cock as is my AA ProSport underlever... :-\