Debate about impact - .22 VS .177

[RedFeather]

I did do a quick search on BC and see where speed is an independent variable in most formulas.  They also say that the constant (G1, G2, etc) is assumed for certain projectiles, etc.  I'm wondering how a waisted pellet fits into some of these calculations?  Is a specifically tailored BC calculator needed?  Anyway, even without a BC formula, it has been known for a good while that the standard pellet shape does not do well as it approaches the speed of sound. 

Here's something that also needs to be taken into consideration, and I add it to this thread because someone recommended wadcutters are being sort of "all-around" hunting fodder.  Wadcutters can display some great accuracy at short ranges, but seem to fall off after twenty/thirty yards.  At "mid" to long-ranges, a lot of hunters prefer domed pellets.  So you need to find the pellets that work best at whatever ranges you are shooting.  Pellet hardness can also be important.  As I mentioned here or elsewhere, a soft wadcutter driven at high speeds (close shots) has been known to do only superficial damage in head shots taken on medium sized game (i.e. raccoon).

[rsterne]

You also have to remember all this "bucking the wind" talk is only referring to dead straight into a consistent wind.  With a side wind of any kind the .177 and .22 react about the same. Very seldom can you reproduce hunting shots going straight into the wind.  You also have to compensate for gusts and multiple or swirling crosswinds etc.  I guess it is like a larger kite just catches more wind while a smaller kite catches less wind but is effected more by it.

The major factor to be considered in a crosswind is the Ballistics Coefficient.... The amount of wind drift is proportional to the DIFFERENCE in the time of flight between the real world and in a vacuum.... There is lots of information about it on the internet from bullet manufacturers such as Speer , Hornady, and Sierra.... The BC for a given shape is proportional to the Sectional Density.... Larger calibers have a greater SD.... The advantage in BC for similar shapes will always lie with the larger caliber....

Bob

[rsterne]

Interesting discussion about penetration comparison between .177 and .25 cal here....

http://www.gatewaytoairguns.org/GTA/index.php/topic,14841.0.html

Just another part of the puzzle.... I didn't see any specific numbers for the .177 and .22 cal Mod. 48s in this thread so I went to Straight Shooters and found that the .177 with a 10.5 gr. pellet and the .22 with a 14.5 gr. pellet shoot about the same velocity ~850 fps.... Using ChairGun's penetration calculator that gives 4.23" for the .177 and only 3.73" for the .22 cal.... Even though the .22 cal has a LOT more energy (~23 FPE vs ~17 FPE).... The .177 with heavy pellets can outpentrate "normal" weight pellets in the .22cal.... Of course if you go to heavy pellets in the .22 cal then that changes....

Now I can see the logic in using heavy pellets in a .177 for game as large and tough as raccoons providing a "fusebox" shot is taken.... Just goes to show that "Impact" can mean a lot of different things.... It also shows I'm always learning.... and have lots more to learn yet.... 

Bob

[Tramo]

Yep, not sure the title was worded right, and not sure the question was asked properly, but the answer is showing it's face little by little....

Thanks for more input Bob.

[rsterne]

for serious hunting I really like it to be going 900 to 950fps.

I agree, although if I have to for accuracy I'll allow 850-950 fps.... Since I shoot mostly PCPs I can achieve that velocity range in any caliber up to .25.... Most of my hunting rifles are .22 cal.... as that's big enough for most of the game I hunt....

I do have one exception.... My most used hunting rifle is a .22 cal PCP Carbine that I use for Grouse hunting.... It shoots 18 gr. JSB Exact Heavies at 700 fps (20 FPE) and it's absolutely DEADLY with head shots.... most of the time knocking the bird off it's feet.... That's one specific case where I prefer the momentum of the heavy pellet more than the extra velocity with a lighter pellet....

Bob

[Smaug]

Great thread. I wish I knew how to subscribe to it.

To back up what Bob has been saying, here are some hard numbers, from the Diana 48 that is often mentioned. I'm not sure if they were calculated (likely) or measured, but I bet they're accurate.

http://www.straightshooters.com/ourtake/ottest48.html

They have similar tables for the few guns they do sell.

Maybe this goes without saying, but the intended use can make the .177 "better" than .22 or .25.  For instance, if I'm wanting to do plinking on a budget, .177 is better, because ammo costs 1/2. .22 airgun ammo costs about the same as 22LR firearm ammo. 22LR has a huge advantage vs. .22 airgun ammo, so at that point, the only advantage to shooting .22 from an airgun is when airguns are allowed and firearms aren't. Or, if one is worried about overpenetration.

Another point is that if the .22 won't penetrate into the body of what you're trying to hit because of its larger diameter, it is less ideal. One needs enough energy to get to the guts.

Making head shots on ground hogs at 85 yards, out of a .22 springer... I would have to see that to believe it. Someone in this thread says he does it.

[RedFeather]

My three cents on the subject.  (Already kicked in two.  )  In most cases, either caliber will do fine.  Now, how in the world did people hunt with air guns back in the early 70's, before the proto-magnums like the FWB124?  Guns were shooting in the 700's (.177) and 500's (.22) but they still took game.  Go figure?  Everyone wants their air gun to be a .22lr - or better!!!- these days.  It's funny to see posts from folks who just bought a Diana 45 or even a 35 or 27 and they talk about how accurate they are, what a great hunt they had, easier to shoot, etc, etc.  Yes, you have to give up a bit on the range but that's all part of the game.  You can still stand pretty far off and take game.  This is not like you will be hunting rhino on the Serengeti where poor performance will equal your last.    Just about any of the current models in the magnum to ultra-magnum classes will get the job done, in either caliber.  And you really can't judged performance by the stats, alone.  Much of the proof still lies in the pudding.  And that's another fun part of the game.  Unless you are totally dedicated to bench rest shooting, etc, you might not want to over-think things.  Consider why you are getting into the sport in the first place.  

Like I said, I happened to buy a nice 54 in .177.  Now, today, I would likely hold off for a .22, but I'm still not complaining.  Both will "get the job done".  And, sometimes, less is more, as they say.

[Mark 611]

I bet you most women won't agree with you on that one! LOL!!!!!!!!!!

[hw77grey]

Are you suggesting thoose with .25 cals are compensating! I like .22 all around, more forgiving I find, if I was 1/2'' out, more often than not it did not matter, and I assume that near misses are less effective in .177. But my opinon can't hold much, I have never owned a .177, not even in my pb's , I find the hmr's far to pricey.

[hw77grey]

And I understand that past 150 yards the 17hmr's performance really drops, I am consistantly able to take gophers at 160 with my 10/22

[JonnyReb]

 Another vote for the .177 if set up right. Just from observing penetration in various calibers both in game and target i'm really thinking more and more that the limited output of a springer works best with light solids(for hunting), striving for maximum penetration rather than impact of ftlbs. Very similar to the preferred use of 7x57 and 6.5x55 mausers on elephants by professional hunters in the early 20th century. They used solid projectiles and went for brain shots. I'd venture to say, that if you took their powerplant and rebarreled the mausers for the larger 8mm or larger slugs, they didn't get enough penetration to drop the beasts. There was a reason they found those light calibers effective. Penetration.  I have never had a critter run off yet that had 2 holes in them. Most of my .177 shots have had both an entrance and an exit hole and those are the ones that, coupled with a headshot, literally go limp and drop. Can't ask for any better than that.  J

 

[xxlbreed]

Have some of you guys heard about "Hawke Chair Gun" ? its free from the Hawke website if you sign up. It has the entire database of pellets .177 to .25's in there, it calculates the POI, balistics, ..... pretty much everything you want. graphs it and puts it in tables. It also has a bunch of other super useful features. Im not trying to sell yall this software.. but I am just very impressed by its performance! Check it out, youll learn a lot by just tinkering with it.

[RedFeather]

Deleted