About two or three years back, I did some fairly extensive testing on several pistol barrels with cryogenic tempering. If I remember right I tested a Sig 229 in 40S&W, Beretta Cougar in 40 S&W, Browning BDM in 9mm, Kel Tec P11 in 9mm, and a Taurus PT945 in 45 ACP. No revolvers, all autos. I was pretty well convinced that it was worth while and had been proven in rifles. I was skeptical about the short tubes on pistols, but like many others I am a techno and gadget buff. Most gadgets are worthless, but evry once in a while you find a real gem, so I keep looking and fooling around with almost any aftermarket item made for pistols - if its in my budget
I fired 10 shot groups at 25 yards from a deviced used for testing accuracy or sighting in a pistol. I was very meticulous (sp?) and actually wrote a short paper on the results althought it wasn't for anyone, just a record for myself. I will look for it and if I find it and anyone is interested I will try to e-mail them a copy.
There was a small increase in accuracy, but not (in my opinion) enough to make a different in a handgun used for combative defense. On average the group improvement was just over 1/4" at 25 yards. By this I mean that the average distance of the rounds from the group center shrunk by 1/4". One of the pistols showed no improvement and actually showed a group that was about 1/8" larger. Keep in mind that these very small differences at 25 yards could be completely written off as human error or influence (felt better, less coffee, just having a good or bad day, in the groove, etc.) The Taurus PT945 showed quite an improvement and the Kel-Tec P11 showed a tremendous (sp?) improvement. The Beretta Cougar showed no improvement, I believe, and the Browning BDM showed a slight increase in group size and the Sig 229 showed a little improvement. This is all from memory and I may not remember it exactly right. Five to eight different types or brands of ammunition were used. Cor-Bon, Speer Gold Dot, Hydra-Shok, Speer Lawman, S&B, Houston Cartridge, etc., if memory serves me. The pre-cryo and post cryo rounds all came from the same box (same lot)and weather conditions were the same to within several degrees, both with no wind and high humidity. The pistols were allowed to cool 5 minutes between each round and two fouling or heating rounds were fired off target into berm before the test was begun. None of the pistols were exactly new. Some had had over 1000 round through them and none had had less than 200. This is only important if you subscribe to barrel break in. I have seen barrel break in occur in a couple of pistols, but I personally think it is rare.
The cryo treatment is also touted as making cleaning easier. If it did, it did not help enought to really impress me. I don't know if it increased velocity as I did not Chrony during this experiment. If it does, I think it would show the same relationship in pistol vs rifle concerning accuracy. Maybe a very slight increase (10-15fps???). If you are interested in a copy of the test (If I can find it - may still be lurking on the hard drive of the computer I don't use much anymore). E-mail me and I will try to get a copy out to you or send it to some one who can properly post it (graphics and all) to this forum.
Would I do it again. Yes, but only on my primary defensive weapon (only my life, and maybe others, depends on it)and any very very serious target pistol (which I don't own any of) under the following condition; I could get it done cheap(<$35)or free. A decrease in group size of 1/4" at 25 yards seems almost a rediculously small improvement in a defensive handgun, but I also carry a spare magazine when many don't They say "If 8 or 12 won't solve the problem, your too deep in the poop to get out anyway" I think they are full of it. A 1/4" improvement might mean the difference in a loved one living or dying if you were forced to make a sniper type shot with a pistol at 15+ yards.
By the way, expending so much ammunition, having numerous handguns and getting so many of them cryoed doesn't mean I am rich, it just means that I am a gun nut like the rest of you, borrowed a couple of guns, and got much of the ammo and all of the cryo work for free. Gotta choose your friends right!
TEX
Any of you folks going to the GSSF shoot in San Antonio, December of 99?