Originally Posted by OKFC05

The barrel is not fit correctly, and it is easy for S&W to fix.
And no, the ammunition has absolutely nothing to do with your problem, and the ammo does not "cushion" the closing.

I agree with the advice to be very specific about the problem, and what mods you want left in the gun. One of our shooters sent in a Sigma last year (there was really nothing wrong with it) with a vague request to "update" the gun he bought used. They updated it all right: the entire sear block assembly was replaced, and all the polished sear block trigger pull smoothing was lost.