I do not have a .177 in a rifle, and both of my rifles are .22 (gas springer and a PCP).
Generally a .177 will be moving faster, then the same rifle in .22, but there are some manufactures who push the .22 at or near .177 fps.
You may want to check out the Hunting Gate over at Gateway to Air Guns: Hunting Gate - Airguns & Guns Forum
Be advised, some of the pics posted there are VERY graphic. I posted one with a rat missing the top of its head. Result of a hollow point.

Now, I can tell you with a .22 rifle using pellets in the 18 to 21grn range will take a ground squirrel, or large rat (10inch in length, not including the tail), with proper shot placement at ranges of 33yrds, with no worries. Both my Gamo gas spinger and Benjamin PCP have done this on a regular basis.

 

More often than not, the .177 will be faster. Mostly that is because it is lighter......a typical .177 pellet weighs about 8 grains. A typical .22 pellet weighs nearly double that. The heavier weight means that, while slower at the muzzle, the .22 will shed velocity more slowly and carry its energy farther than a .177 pellet.
Pete

 

All well and good, but..

Let's think squirrels, crows, maybe even rabbits, here. I think all would agree that either .22 or .177 is sufficient, again within normal ranges. But how about inherent accuracy? I have no experimental experience with either caliber in air guns and I read about .177 tumbling after slowing to subsonic speeds and how some air guns are very accurate with .22 but not with .177. Given 50 yds max. shooting range, speed of sound is 1000 fps (+or-) so I wouldn't a pellet starting near 1000 fps maintain near sonic speed for that distance? Hence, pellet tumble is moot. Does anybody have any real life experience with the .177 under those hunting conditions? Then all I have to do is wade through the product hype to find the right gun.

 

Let's think squirrels, crows, maybe even rabbits, here. I think all would agree that either .22 or .177 is sufficient, again within normal ranges. But how about inherent accuracy? I have no experimental experience with either caliber in air guns and I read about .177 tumbling after slowing to subsonic speeds and how some air guns are very accurate with .22 but not with .177. Given 50 yds max. shooting range, speed of sound is 1000 fps (+or-) so I wouldn't a pellet starting near 1000 fps maintain near sonic speed for that distance? Hence, pellet tumble is moot. Does anybody have any real life experience with the .177 under those hunting conditions? Then all I have to do is wade through the product hype to find the right gun.

Sorry as I cannot speak to the inherent accuracy of a .177, but beyond 30yrds for a .177 at anything other than paper, I would question its power to take any of the game you list as a humane kill. (disclaimer: Yes I understand shot placement, but I am assuming a narrow window of opportunity for a live, moving target)

 

I don't have personal experience with shooting a .177 that breaks the sound barrier. But a friend of mine does and had best results using a heavier pellet (JSB 10gr) to keep his shots under the sound barrier. He has one of the Gamo break barrel rifles, sorry I can't remember which one. But he can hit an 8" target at 100 yards repeatedly.

I would imagine coming out of supersonic would throw a pellet way off because it doesn't have much weight behind it. And because of its lack of weight it would probably come out supersonic rather quickly. But I'm just speaking from my meager understanding of physics.

I think .22's are the way to go but they do have a down side in ballistics compared to a .177. But both calibers are pretty capable. I do know that both calibers can quickly dispatch a pigeon at 50 yards with a well placed shot.

I would say anything you can hit a 1" target with at 50 yards with a reasonable velocity should be what to look for.

Mcg, are you looking at PCP air rifles?

 

Oh! Ukelay, you dont really mentioned it, but talk around it (not intentionally), but wind is a huge factor with air rifles! Take centerfire and X it by 10, even at short ranges (20yrds).
More so with .177 vs .22.

 

At least once each year i will go someplace to hunt smallgame for three or more weeks. I carry a 45 caliber muzzle loader, and a 22 caliber air rifle in addition to a handgun for snakes. I spent seven months in the Raft River Range of the Rocky Mountains in 2011 with nothing but air rifles and slings. For anything larger than doves I recommend the 22 caliber because I have connected solidly many times with a 177 only to have birds to still fly away to die someplace else. Snowshoe rabbits were not even fazed by 177 pellets, so I quit using it altogether although it was very fast and accurate but too tiny for clean kills. The 22 caliber needs HEAVY PELLETS, the heavier the better. Though it lacks the range of the 177 it can drill a pigeon out to sixty yards, it kills rabbits cleanly, it even kills raccoons too. I ate very well during those seven months on at least a dozen Eurasian collared doves and pigeons each day, and rabbits occasionally. My Beeman Spring powered 22 caliber at 600 fps using 21 grain pellets was ample power. I will state that I dislike break barrel types because they will hit either at 50 feet or at 50 yards consistently shooting at one of the other range at each shot! I have wrapped more than one break barrel around a tree. Get a Side Cocker for precision hunting and leave the break barrel Toys at home.

 

I am inclined to agree with Sope Lote about break barrels, but if you go with a break barrel, look out for barrel drop. Varies with the scope you may use.
The Gamo I had, with the scope they provided, it was dead on for a 4x32 scope.
I replaced it with a Bushnell 6x18x50 AO scope. And had to get a UTG barrel drop mount.
It is very accurate with that combo.
But my PCP still gets more use.

 

Inherent accuracy???? Hmmm. It would be nice to see a test of one to another./
What I do know is that all serious...olympic quality...air rifles are .177s.....now most of that is due to rules as .22s are not allowed in ISSF match shooting. One wonders why.
Even in Field Target match shooting where .22s are allowed, the .177 dominates.
Pete

 

Dang Nab it ! Decisions, decisions.

That's what I like/hate about these discussions. Just when I think I know what to do somebody brings up another good point. Mo betta too much than too little info, I guess. I noticed the preponderance of .177 in competition but just ignored that - until now - I hadn't considered scope problems or side cockers - until now - and I sure hadn't considered PCP's. Frankly given my past history I think the way to go is to just get something, see how I like it and then get another and another one. After all, it's only money! But I do appreciate the info!

 

That's what I like/hate about these discussions. Just when I think I know what to do somebody brings up another good point. Mo betta too much than too little info, I guess. I noticed the preponderance of .177 in competition but just ignored that - until now - I hadn't considered scope problems or side cockers - until now - and I sure hadn't considered PCP's. Frankly given my past history I think the way to go is to just get something, see how I like it and then get another and another one. After all, it's only money! But I do appreciate the info!

I like the way you think!
Yeah, I started out thinking,
"Eh, all I need is a break barrel. No need to spend anything more than $300 right?"
And now I have a PCP, and a bin full of pellets.
Gotta admit, when I had a rat problem, the 10rnd magazine, bolt action was much better then having to re-charge the break barrel, seat a new pellet, close the barrel, re-acquire, and take the next shot (if I missed or if it was not a clean kill, I dont like to see animals suffer).

 

There are other question that might be even more important than .177 vs. .22. Such as the weight and shape of the pellet. I think a chronograph might answer a lot of questions,(such as which has more muzzle energy?)but I haven't broken down and gotten one. Some of the heavier pellets have longer skirts, which makes them more accurate. Hollow point .177 vs. round nose or pointed .22? Heavy .177 vs. light .22? Light .177 vs. Heavy .22? I think a pertinent question, as far as hunting, is how much penetration are you getting?. If the .177 is passing clean through, then the .22 might be better. But if the .177 isn't going clean through, it might actually be more lethal. Most people seem to disagree with me, but I'm not a big believer in the bigger hole is better theory. A smaller, deeper hole may be more lethal.

My short answer is, a powerfull gun would be better in .22, but a less powerful gun would be better in .177.

Whatever you use, go for the clean kill. Even squirrels deserve a quick death.

 

The skirt length may have some effects on accuracy.
But my Benji M-Rod has a better preference for head diameter then skirt length (i.e. 5.52mm vs 5.50mm).
Even the higher end Professional Line from RWS Meisterkugeln (5.5mm) does not group as well as JSB Match Diabolo Exact Jumbo Heavy (5.52mm).
Very well could be a mix of head diameter and skirt length.
All the shots I have taken have passed through or, well, took the top off the head of a rat (I was using Beeman Crow Magnum HP). Like I could see into the cranium cavity, most of the brain was gone.

What do you mean by "powerful?" Like FPS? Energy the pellet can deliver when it reaches the target?

 

I once had a Side Cocker 177 that did 1400 FPS which stayed inside 1/2 inch at 100 feet, but scores of skuirrels ran off to die someplace else. With my 22 caliber Side Cocker's i do not need ultra high velocities but i do need heavier pellets. From 22 to 28 grains are available, and the Eunjin 28.8 grain pellets will easily know most anything down and keep it there. Jim House is America's leading authority on Air Rifles and The Backwoodsman Magazine has featured articles by him which have greatly influenced my permanent choices in air guns. I refuse to ever own another Game Wounding 177 caliber. It's just indecent how the 177 wounds much more often than it kilss, despite its inherrent accuracy.

 

I think ballistics, ammo shape and weight, influence of wind, are more amplified with air and can be seen at short, mid, and longer ranges.
An excellent training tool, as well as maintaining the fundamentals.
Scop' Lote' I agree with you, I would rather have the extra energy downrange and downrange for air can be as little as 20yrds.

 

My very first time using an air rifle on skuirrels was at Sopchoppy Florida using a side cocking 1400 fps 177. I averaged nine hits per skuirrel before they finally died a slow death and fell out of the trees. I switched to a side cocking 600 fps 22 caliber air rifle using the 21 grain dome pellets and I have cleanly killed skuirrels, raccoons, rabbits, and hundreds of doves since then with mostly one shot kills. Even Canadian Grey wolves noticed when they were hit with the 22 pellets, never returning for another look. I would not chance shooting a wolf or a cougar with a 177 caliber mosquito to chase them away. It might be the last memory I ever had.

 

Accuracy is more a function of how well made the rifle is and "does the shooter know how to shoot an airgun"?
Shooting the airgun required a different technique from shooting a firearm.
I've tested .22 and .177 airguns, good ones, in various mediums and find the .22 will display more impact damage than the .177. This includes modling clay, playdough, duct seal, b-get, water filled alum cans and lots of other things fun to shoot with the airgun.
Then there is the results on small game, i.e. squirrels and crows. The .22 seems to put the critters down much better than the .177. I have no hunting experience with the .25 cal pel guns.
Pyramydair.com has a lot of articles on airgun hunting and the .22 bore is recommened hands down over the .177.
Pyramydair.com has good prices and a huge selection of products from all over the airgun world.
They also have a huge selection of assessories and ammo.
As an important after thought. Many airgunners (and shooters of firearms) are willing to spend the bucks for a decent airgun but try to get the least expensive scope that appears to be o.k.
I made that mistake a couple times only to replace the junk with a good glass.
The best airgun rated scope I have thus far is the Hawke brand. Hawke just got into the modern firearms scope sight market.
I had one scope that went south on the 5th shot from an RWS 48. The reticule fell right out to the bottom of the tube.
I'm sure others here can recommend good scopes for airgun use than just Hawke.