Bought a new M&P45 on Saturday, and put (well, tried to...) 200 rounds through it today. I wound up getting a fail-to-feed on about 30 rounds (hanging up on feed ramp). Ammo was a mix of 230gr. Hydra-Shoks, 230gr. American Eagle, and 230gr. Magtech FMJ, and failures happened approx. equal number of times with each brand.  

Anyone else experience this with a new full size 45?

Could be a couple of issues.  Are you mixing hollowpoints and FMJs in the same magazine?  Sometimes mags won't feed with mixed ammo like that.  The other problem that we have had with our issued M&P45s is that the mag springs sometimes get bent.  Disassemble your mag and check that out.

Did you clean all the factory oil/grease/preservative and relubed?

AE is a decent ammo IME, so I would discount that. If all else fails, call smith. They have CS second to none in the industry.

I first would look at the magazines, your shooting grip, ammo and proper PMCS on the pistol.  If all of those are good to go I would next look at the feed ramp and recoil spring assembly.  I have an M&P .45 ACP midsized and it has been flawless.  I hope this helps.

I bought a full size M&P45 about six months ago and experienced a similar issue with it while using Blazer aluminum cased ammo. Mine has not had any issues while using brass cased FMJ or hollow point ammo, but it still will not feed aluminum casings at all.

I was wondering how you guys were making out with them. Mass seems to like theirs. My 45c has been 100% and will hand cycle empty brass. I did use a little Flitz on the Feedramp.

I  absolutely love mine.  I actually have two, one issued, and one personally owned that I bought before we had ours issued.  Both of mine have been flawless, but a couple of the guys at my small department have had FTFs with bad magazines.  We got new mag springs in them, and a few spares just in case, and we haven't had as many issues.

Magazines - both factory new, but will disassemble to check for issues.

Shooting grip - have never had an issue before with any weapons...

ammo - see above for ammo used. I could see Magtech being sketchy, but have never had problems with AE or Federal HS before. Also, ammo type was not mixed in magazines.

PMCS - weapon was purchased new, field-stripped, and relubed with Slip 2000. Malfunctions began immediately with first magazine.

I was hoping to qual. with this one next month in order to carry on-duty, but will need to put a bunch more rounds through it (w/o malfunction) before I even think about carrying it.

Thanks!

Give it a couple hundred to settle in.

Tried to hand cycle 50 rounds of 230 gr. HydraShoks through it this afternoon...had @ 70% malfunction rate. I always put 800 - 1K rounds through a weapon before I carry it for duty/defense, but I've never had one that had this malfunction rate, and don't believe it'll "settle in".

It appears that the rim is catching the extractor and not allowing the round to chamber.

I sent an email to S&W customer service...hopefully I can get it returned and back before qualification at the end of the month.