M&P9 Accuracy issues... is it me??

[netchemica]

So I own an M&P 9 core and I have an RMR installed on it. I had a regular M&P9 before this and I also had accuracy issues with it, but I just chalked it up to it being the original version which was plagued with accuracy problems.

Well, I got this gun, shot it a lot, couldn't group for shit. I installed an Apex FSS trigger in it, helped a bit, but it was still pretty bad. I was consistently getting ~7 inch 17rd groups at 10 yards.

So I figured that it was still a barrel issue, I could feel the barrel move forwards/backwards and side to side in the slide. I decided to send it out to G&R Tactical to get their oversized Storm Lake barrel fitted. I waited about 8 weeks, it finally got sent back, and I picked it up yesterday. There is virtually zero movement in the slide and it feels really solid.

The range trip was still pretty disappointing. I was barely able to pull off a 5 inch 17 round group at 10 yards.

Now, I really don't feel that it's shooter error. I shoot significantly better with my M&P9c with a DCAEK trigger, my Ruger MarkIII with a VQ trigger, the 40s&w p229s at work that have a heavy double action trigger and tons of rounds through them, and my buddy's stock G19. Even the XD9 I sold 6 years ago showed better results. I highly doubt the RMR is moving on me. I don't remember what I torqued it to, but I know I looked up what the fastener is rated for and I used my FAT wrench to torque it... I then used a paint marker to set up witness marks to make sure it doesn't loosen. I was using some cheap Freedom Munitions ammo for this run, but I don't feel like they would make that big of a difference, especially considering my M&P9c with a factory barrel had a group half the size with the same ammo.

Can anyone help me diagnose what's going on? I feel like this gun is capable of much more than it's putting out. I would like put it into a vise and test it properly, but I don't have access to one.

If anyone is curious, here's a photo of the gun that I took with my phone: http://i.imgur.com/uh2r3P6.jpg

[Mjolnir]

What's the twist rate and what is the ideal twist rate for 9mm?


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"One cannot awaken a man who pretends to be asleep."

[netchemica]

I don't know what the ideal twist rate is, and I can't find any info on the Storm Lake website. I found a bunch of results on random forums that showed the Storm Lake 9mm barrel being 1 in 16.

[Inkslinger]

Have you shot it with just using the iron sights? You listed quite a few guns you had success with. Unless you had a RMR mounted on all of them, I would look there for an issue.

[ezveedub]

Earlier M&P9s had accuracy concerns and S&W increased the barrel twist rate to the same as Glock from what I read about a year or so ago.

[Toecheese]

Earlier M&P9s had accuracy concerns and S&W increased the barrel twist rate to the same as Glock from what I read about a year or so ago.

Bingo......I have never had great luck shooting M&P's across the board. It's probably me, but who knows. I only carry an M&P 40C which I actually shoot pretty well. Try swapping back to an OEM Smith barrel OP?

[netchemica]

Bingo......I have never had great lock shooting M&P's across the board. It's probably me, but who knows. I only carry an M&P 40C which I actually shoot pretty well. Try swapping back to an OEM Smith barrel OP?

I had awful luck with the factory barrel also, which is why I decided to send it out to get a fitted barrel. Would anything change by trying it again?

[Tigereye]

Are you shooting off a range bag or what?

I ask because of a tip I got on the Brian Enos forum years ago regarding M&P's. The tip was to not rest the gun on the bag but only rest your arms on the bag. It greatly improved my accuracy and groups with the M&P. But, I've never seen someone shoot a 17rd group. I probably couldn't focus that long.

[Tequila45]

Has any one else shot this m&p? Not saying it's operater error but it would help to get a better diagnosis.

[jayfl]

I was barely able to pull off a 5 inch 17 round group at 10 yards.

Something is definitely wrong there.

I have a 9L slide with SL barrel fitted by Grant with a RMR cutout from ATEi. This was unsupported slow fire @ 15 yards (closest photo I have to 10 yards):

If you're having problems with that setup, I'd assume there's an optic mounting problem, jacked up optic or possibly shooter error (no offense). Are you seeing any change in zero on the RMR relative to the irons?