S&W M&P 2 9mm Easy problem-return to battery

mogwan

Member
Joined
Jun 15, 2012
Messages
113
Reaction score
65
At 71, I need a bit of an advantage as my Sig P229 and CZ 75- both M&P semi's are VERY heavily sprung. After 60 yr shooting, I still own only 1 striker fired pistol, a P365- where precision accuracy is not as important as reliability. I bought the Performance Center model to get a hammer/sear instead of striker gun. Bare bones stripped it to remove any packing grease or oils, lubricated it and went to the range to test fire it using factory pack, non-reload, brass case 124 gr LRN with a power factor between 137-140. After approx. 30 rounds- all with the same mag, the firearm frequently refusees to return all the way into battery- giving me no trigger/hammer sear engagement. I then need to retract the slide about 1/4" or so back, then return to the actual 'slide-stop' position and the trigger will re-engage the sear. Took it home- and it will 'dry fire' w/o a mag- no problem. However, insert either of the new mags empty, rack the slide / override the slide lock- do this about 10 times and 6 out of 10 times the slide fails to return to battery with an empty mag in and letting the slide 'snap' down the slide rails; with full, unimpeded-no 'limp wrist or 'finger on the slide' tavel. The trigger will just be 'dead' and pulling on it offers no resistance all the way to the frontstrap stop- apparently with no sear/hammer engagement then hammer drop. Somehow, i don't think it's normal. My CZ or Sig will give me 'trigger engagement' w/an empty mag after the slidestop is dropped. Any ideas-advice welcome. Somehow, i don't think my 'Manual of Arms' is the problem...
 
Register to hide this ad
SKU 13223

MODEL:M&P SHIELD

PC M&P9 SHIELD EZ PRTD BLK TS

Yes, the PC Shield EZ is not striker fired and has no external hammer... think more like 'Humpback Bodyguard.'
The hammer is concealed under the slide.
 
Last edited:
I'd be inclined to...

...get back to the S&W mothership, however they are in the middle of the big move to TN. I think I'd try running it by hand without the recoil spring (both with and without mags and ammo) and see if it's binding up near closing. Hold the top of the gun down to keep the barrel in place. If it isn't binding, you could probably get S&W to send a new spring without having to return the gun.

Since the slide comes so close to locking into battery, there is probably nothing wrong with the feed ramp. Just in case I would surely try some name-brand ammo in it. I'm not sure why, but a rough or short chamber could be keeping the bullet from sliding in easily. Might do some 'Plunk testing' with the barrel out to check that out.

If there is nothing wrong with the feed ramp and the ammo is ok, it would have to be in the guides, spring or the barrel. I'd assume that the round cleared the magazine since it gets so close to locking. I had trouble with my magazines as the mouth of the case would hang up on the front of the mag but that doesn't sound like what you have.

Oh, and I think I'd try a lot of oil just to see if it clears it up. I know you don't want to run it that way, but just as a diagnostic.
 
Last edited:
I have seen some folks post that dry fire does not equal live fire in terms of return to battery. It does seem that based on your analysis that something is not moving as it should. How many total rounds have you fired through it?
 
I have a couple of guesses. First, check that none of the roll pins that secure the innards to the frame have backed out. Second, it's possible the recoil spring assembly went into a slightly "off" position when you reassembled it after initial cleaning. It moved some more after the first 30 rounds and is now interfering with the slide in a way that prevents it going into battery.
 
I'm old school and like to run my guns wet. Using a bit of Moly grease on slide rails, barrel & bushing, recoil spring, etc. followed by a few drips of synth oil on all lockwork, bars, etc. so lube isn't the problem. About 50 rounds of fresh, 124 Gr. 9mm Magtech going into new mags with a bit of graphite powder lube and -0- lip deformation. The fail to return to battery happens both with & without firing live rounds. All pins are flush- no apparent obstructions. I'll check the position of the recoil spring rod. I had one issue of a 'slide lockup' when removing the slide as i didn't notice the left & right flat clearance cuts where the rod end meets the barrel lug so i put a small dab of white nail polish on the top to remind me of the correct orientation. When new, the slide rails were VERY lightly stoned with #600 sharp/flat India followed by #1000 flat Arkansas for 2-3 passes to remove any possible burrs. no clearance change- only smoother surface that still holds lube.I'm thinking it's related to mag position or slide release mechanics. Going to the range on Tue. and will see if i can "Shoot it away" by gently force-feeding rounds if necessary and looking for high spots after a coat of black Moly grease. Thanks all for your replies-mog
 

Latest posts

Back
Top