M&P 9L, can it be accurate?

[Mickster]

I got a PM from a well respected gun writer and photographer advising me that some M&P's can benefit from re-crowning the barrel. A close inspection revealed chatter marks on the crown I never noticed before so I had it re-crowned by a master builder of bench rest rifles.

The shooting was done just as before, 5 shot groups off sandbags at 31 yards with mostly the same ammo.

Results were interesting in that a few of the groups came in at 2". Some were close to 5". Out of 20 groups using a variety of loads and factory the best groups were shot using 4.1 of Titegroup with the 124 XTP bullet. The 147 XTP came in a close second but the most consistent were the 124's. Taking all the groups, with all the different bullets and powders, adding them up and dividing them out gave an average group size at 31 yards of 4".

That makes it better by about 25% as compared to the over 5" average before re-crowing.

This is a step in the right direction. What's next? I noticed the slide to frame fit is tight at the rear and loose at the front with up/down movement. Don't know if that makes any difference.

Is it possible to bend those tiny little rails in the frame (sort of like the 1911 trick) to tighten it up or are they so hardened that doing something like that could break them? Perhaps an M&P gunsmith could chime in.

[want2race]

I've too have noticed the slide moving as the firing pin drops. I look forward to the parts that Randy puts out.

When I first got the 9Pro (borrowed), I tested it at 25yards. I don't know if it was a fluke, but I shot a 2" group off hand at 25 using Blazer Brass. Steel1212 was with me and let out a few expletives when he saw it.

I think with the Melonite finish inside the bore, the more rounds down the tube the better it will get. For a new gun it may even be worth running a little bore paste down it to polish it up a little.