I have a 229 that fires .40s&w without a hiccup but often fails to return to battery when firing .357sig. I have tried swapping out springs but have not been able to eliminated the problem. Any suggestions?
Hmm, I have the same setup and never had a hint of a problem with it. Got the rails well oiled and slicked up? Probably the recoil impulse is much sharper with the .357SIG than with the .40S&W, so maybe the slide is binding slightly. Just a guess.
Yeah, I think it is something binding ever so slightly. Newton's law is probably having an effect. You are pushing more mass out the barrel with the .40S&W then you are with the .357SIG, and it is making a difference.
Maybe some polishing and smoothing of the sliding surfaces will help out.
Yes, it can be more in total recoil, but the impulse is different. The .357SIG feels much sharper in recoil than the .40S&W. That could be enough to make a difference on moving the slide back. If the slide is catching at the peak of recoil with the .357SIG because it hasn't moved back as far as it would be at the peak of recoil energy in the .40S&W, that could make all the difference.
As I mentioned, this is just speculation on my part and is what I would look at if I were having this problem.
The most common reason I have run into causing this problem in any handgun is the feed ramp. Either the angle is off a bit or a good polishing is needed. A little bit of fitting and tweaking of the barrel to your specific gun is probably all that is needed.
Nothing official, but is appears that the block is off slightly and is binding on the frame. I have stopped using the .357 Sig barrel and just shoot the .40. It is still one of my favorites guns. MOF, I put Coco Bolo wood grips on it......totally pimped