The wife's P238 has fed everything we've put in it so far. Only issue was a stovepipe with some Prvi ammo the first time out that I attributed to her limping it as she hasn't shot an semi-auto in years. The Blazer aluminum stuff is noticeably hotter than an other factory stuff she's fired in it. Last time out, her fourth with the gun and shooting Fiocchi XTP'S, she made a free-hand five shot group that you could cover with a quarter with three nearly in the same hole.
It was only fifteen feet, but she's easily shot more in the month she's had the pistol than in past 10 years, so I was still impressed. I guess we got lucky.
Slide to frame fit on P220-series guns plays no real role in accuracy. While many SIG pistols are moderately "tight" from the factory, they do loosen up through use. Some of the SIGs I used to shoot would literally rattle when I shook them hard. A gunsmith can actually remove the rattle by re-fitting the barrel but it won't do anything other than stop the rattle.
What matters is that the barrel locks up tight with the slide. The slide has the sighting system, so as long as the sights and the barrel remain repeatably aligned then minor variations in the top end's position relative to the frame are meaningless.
While you certainly need no supporting evidence, I will add that while my SP2022 has to have more rattle and slide to frame slop than any other modern pistol I own, it will chew a single hole if I do my part. I can find no appreciable difference in accuracy between it and my Sig Classic and Beretta pistols.
I picked up a 228 today, before reading this.I'm going to make an effort to work with the sa/da because I also have a hk45c coming.So the M&P will be sitting it out for a while.I've looked for a srt kit they are hard to come by.
If I can pass on the advice SLG gave me -- learn to love the DA Sig trigger pull. Get yourself a snap cap, and DA the crap out of your pistol until you own DA. When you do live fire drills, do fewer drills that involve one DA shot and a bunch of SA presses, and focus on lots of two shoot drills until the DA/SA transition becomes subconscious.
When I was learning my Sig, I would put up (2) 2" circles at 5Y. Draw and shoot one (DA) to the left dot, and then transition to the right dot for the SA shot. Decock, holster, repeat.
I also used (2) 3x5 cards @ 7Y for the same drill.