10mm vs 40 S&W Recoil

[KBintheSLC]

Lately, I have been shooting a lot of .40 S&W through a Lone Wolf conversion barrel in my Glock 20. I have been noticing how snappy the .40 is even compared to the 10mm. Yesterday, I took out some various 10mm loads from PMC and DoubleTap as well as a box of 165g Fiocchi .40. Much to my surprise, the .40 ammo was displaying more muzzle flip and showed worse accuracy than even the hot 10mm loads from DT. And the PMC 200g 10mm felt like little more than a gentle push.

I know recoil is pretty subjective, but to me it felt like the 10mm loads were easier to shoot than the .40 S&W. The pressure levels are pretty close in both cartridges. Is it just me or have others had the same experience?

 

[gofastman]

I was just at the range yesterday and mirror your thoughts exactly, in fact I was gonna post something about it. It seems really strange that a .40, especially the low power Federal target stuff I was using, would recoil so much in a gun built like the G20.

FWIW, I was there testing out the reliability of the new #20LB ISMI recoil spring combined with the conversion barrel (100%) so maybe the heavier spring has something to do with it, but if I remember correctly it was snappy with the stock 17LB'er too, perhaps an 11 or 13 lb spring is in order?

 

[wow6599]

I feel the same way, that's why all my "fotays" are gone.....but I do have a 40 S&W LW barrel for my G20 because of all the free range brass I get.

 

[gofastman]

can anyone think of an explanation for this phenomenon?

 

[KodeFore]

Just wondering, have u tried shooting the .40 in G22? Mayby its something to do with the conversion? isnt 40 just a shortened 10? the conversion barrel? Does that just extend the chamber for the shorter round?

 

[loadedround]

Are the bullet weights the same in 40's vs 10mm's? That could make all the difference as pertaining to Newton's Second Law of Motion.

 

[nelsonal]

Maybe, faster powder used in the .40 vs the 10mm?

 

[Carne Frio]

I have noticed that when shooting my M610. I think it is
due to 40 S&W being loaded to near it's max potential and
much 10mm not being loaded that hot. When I shoot 10mm
200gr slugs loaded to near max, it is snappier than the 40.

I am about to order 40 S&W barrels for my M20 and M29.
How accurate and reliable is the Lone Wolf in your M20 ?

 

[wow6599]

How accurate and reliable is the Lone Wolf in your M20

I have both a 40 & 10 LW barrel for my G20 and they are not even close to being as reliable as the stock barrel. They have better support, but have a tendency to give me feeding problems......about 5 failures per 100. Great for target shooting and reloading, but not something I would count on.
YMMV

 

[alpha6164]

Think of it this way. The 40 is basically +P. This is why there is no +P in any factory 40 ammo. It is already loaded to max pressures, and further reason there have been some kb in glocks with less that desired chamber support. The 10mm is not loaded to max pressure. Most 10mm ammo even double tap are still loaded to about 36,000-37,000psi. There are documents floating around that the original Norma pressure was around 44,000 psi. I am sure you if you load the 10mm to those pressures then the comparison might even out. With all that said i love my Glock 20 with Lone Wolf barrel

 

[josephbw]

I have an XD40SC and a Kel Tec P-11 in 9mm. My .40 is a lot more controllable than my 9mm. Less muzzle flip, more accurate, very easy to get back on target, and just an enjoyable gun to fire. It may be the difference between the design of the Glock and the XD that makes it easier to shoot. Please note I am not putting down the Glock, just offering another possibility. Also the weight of the gun will make a difference in felt recoil too.

 

[KBintheSLC]

FWIW, I was there testing out the reliability of the new #20LB ISMI recoil spring combined with the conversion barrel (100%) so maybe the heavier spring has something to do with it, but if I remember correctly it was snappy with the stock 17LB'er too, perhaps an 11 or 13 lb spring is in order?

Could be... I was using a 22# spring for all of the loads. I'll try it with the stock spring and see if it changes anything.

How accurate and reliable is the Lone Wolf in your M20

I have had 100% reliability with the 10-40 conversion barrel so far. My other 6" 10mm LW barrel sometimes fails to feed due to the long cases and the tight chamber. I think the 22# spring helps with that. Accuracy is very good, but not quite as good as my stock 10mm barrel. However, POI is basically the same out to 50 yards with both so I don't have to mess with the sights.

Are the bullet weights the same in 40's vs 10mm's?

The .40's were 165g and the 10mm's were 165g and 200g. The .40 "felt recoil" seemed to be snappier than any of the 10mm loadings.

Just wondering, have u tried shooting the .40 in G22? Mayby its something to do with the conversion? isnt 40 just a shortened 10? the conversion barrel? Does that just extend the chamber for the shorter round?

I have never shot a G22, but I have shot a G23. The recoil felt pretty normal, albeit a bit punchier than my 9mm. I never noticed the snappiness of the .40 until I compared it side-by-side with the 10mm from the same gun. I would think the recoil would be even less in a heavier gun like the G20. I am puzzled.

 

[6Covered]

I have a G29 with a LW 40 barrel also. I mirror the same results. The 40 is much
more snappy. That's not to say the 10 is a pussycat.

I have had good results as far as accuracy and reliability with the 40 Lone Wolf barrel. From my experience, I would recommend them.

Jon

 

[DasFriek]

I found the same thing back when i owned my G20 and i also had a .40 LW barrel with it.
Much more muzzle flip with the .40 even over the 200gr DT's.

This past weekend at the range i took my 1911 and SA XD SC .40 both and i was much faster on repeat shots with the 1911. A 22lb recoil spring really smooths that gun out.
But the .40 took some practice to keep the recoil under control for follow up shots.

Also im comparing a heavy 5" barrel gun against a smallish lite 3" barreled gun.
I owned a Taurus PT145 .45acp single stack which was about equal the the XD SC in size and weight. And it was just as much a handful as the XD .40 is.

So if you go throw 10mm and .45's in small guns the .40's tend to be made in recoil will once again become a factor.
But the bad part is the .40 will do it in large guns also which usually tame other rounds.

I still carry the XD .40 and will continue. I just need to keep up on the practicing.

 

[Skylerbone]

Every manufacturer uses a different mixture of bullet weight, bullet composition, bullet style, bullet diameter (yes, there are some small variations), powder and finally charge. Add OAL and crimp in for fun and every round is likely to impart a different signature when fired.

The best way to control any firearm (aside from propper grip; ) is to load your own ammo. Using a 150gr. Nosler HP with 5.0gr. of TiteGroup my 4 1/4" barrel M&P averages 850 fps. While it's not enough speed for propper expansion of the bullet it drastically reduces muzzle rise and recoil allowing for quicker follow up. 5.5gr. moves it safely into the 1000+ fps range where expansion is assured (by my testing) and recoil is still more controlled than most factory loads.

I've found the same to be true of 9mm loaded down to around 950 fps. Suddenly my wife could reliably control her pistol!

 

[PO2Hammer]

It's been a couple years since I've had a .40 barrel for a G-20, but it always seemed softer shooting with .40.
Maybe your shooting full power .40 and the 10mm your using isn't. Pressure could be substantially higher in the .40 load.
I can't imagine any .40 would recoil more than full power 10mm.

 

[KBintheSLC]

Maybe your shooting full power .40 and the 10mm your using isn't.

I know the 165g Fiocchi .40 is loaded pretty hot, but the DoubleTap 165g 10mm is no pussy cat either... moving well over 1400 fps. That's at least 200 fps faster than the hot 165g .40 loads.

 

[gofastman]

Maybe your shooting full power .40 and the 10mm your using isn't.

I too, shoot Doubletap stuff in 10mm.
My .40 ammo was Federal 180gr target stuff, around 370 ft lbs

 

[Rokman]

I feel that the recoil in my M&P.40C isn't that bad. I do think that I feel more recoil in my G23. I don't think that either is that bad though.

 

[MolleMan]

got a question, guy in the gun store said that 10mm is the most powerful round that glock has, so in self defense how is he comparing to the .45 and the .40?

my taurus pt101 in .40 shoots great, recoil is better than most of my pistols including my 9's. and follows up good.shot a S&W Sigma .40 and it was pretty snappy but not uncontrollable though i guess. big weight difference their too though.

 

[MTMilitiaman]

I believe the SAAMI specs for the max operating pressure of the two is 35,000 for the .40 and 37,500 PSI for the 10mm Auto.

I run a 20 pound spring in my G20 with a KKM barrel. Never saw a use for a .40--that cartridge is a solution is search of a problem in my opinion and if I had my way it would fade away into obscurity. The more useful cartridge of the two, the 10mm Auto, got screwed in the popularity contest. But I think that considering it lacks the military history and nostalgia of the 9mm and .45, and the brand name and commercial support of the .40, it has done alright for itself based purely on it performance. People said the 10mm was dead two decades ago at least, but it continues to have a devote fan base, myself included. I don't think it will ever be mainstream, but as a Metalhead, I am okay with that. Pretty much everything mainstream sucks, including the .40 S&W.

I like the Doubletap stuff. Mike does it right. The 180 gr Gold Dot load is awesome. I also like the 175 gr Silvertips as a good moderate standby load. I know either of these loads will let you know you touched something off. They can be a little snappy. But they aren't abusive and the thing that always strikes me about my G20 when I am shooting it is how much I feel like I am getting something for nothing--more performance, more blast, more fun, and more utility--with very little in the way of added recoil or expense. I have seen a 16 year old girl run my G20 with full power 10mm and her smile when the slide locked back was almost as big as my own smile when the slide locked back after my first mag through the thing. I just try to remember it is an autoloading .357 Magnum, and I treat it as such, so I don't expect .1 sec split times.

The only .40 I've ever shot was a friends SIG Pro. Maybe it was the change in the grip angle and the higher bore axis, but it definitely seemed snappier to me. In fact I dumped a mag through it then handed it back to him and told him to keep it, then went back to shooting my 10mm.

 

[gofastman]

perhaps the 10's higher energy expends itself in snapping the slide back more rapidly, transferring less felt recoil to the shooter, the energy gets "burned off" before it even moves the frame of the gun
I'm not sure if I'm describing it very well, but it makes sense in my head

 

[KBintheSLC]

Maybe, faster powder used in the .40 vs the 10mm?

It may very well have something to do with the type of powder used. I don't know this for certain, but I believe that most .40 loads use a very fast-burning powder that causes the pressure to reach peak levels as quickly as possible. The 10mm might have a higher max pressure, but it may take longer to reach the peak. The faster the rate of expansion to terminal pressure, the faster the gun recoils, hence feeling "snappy". This is the only logical explanation I can come up with that does not defy the basic laws of physics.

 

[KBintheSLC]

got a question, guy in the gun store said that 10mm is the most powerful round that glock has, so in self defense how is he comparing to the .45 and the .40?

The 10mm is in fact the most powerful round supported by Glock right now. It's energy levels are in the 600's and 700's whereas the .40 and .45 are in the 400's and 500's. I have never tried it on a human attacker, but I can only assume that the 10mm would make a fantastic round for self defense.

 

[9mmepiphany]

The 10mm round was championed by the late Jeff Cooper (father of modern defensive handgunning) as the Perfect Fighting Round to replace the .45ACP. But it was originally spec'd at a much lower level than Norma originally introduced it. It was meant to throw a big enough (.40), heavy enough (180-200grs) and fast enough (900-1000fps) to be controllable...and have increased capacity (10+)

Norma over loaded it for the marketing advantage of Power...it was never as powerful as the .44 AutoMag...and destroyed it's fighting ability (like the .41 Mag).

The FBI load of the 10mm went a bit much the other way, but was very controllable. When S&W introduced the .40 in a 9mm length cartridge, the pressure curve became much sharper...and hence perceived as being more