M&P .45 slide jams at full rear

[elton01]

Hi all,

I bought a full size M&P .45 six months ago. In that time I've fired both FMJ and ww cast lead bullets through it. It's had equal number of both, amounting to a total of 800 rounds. I've kept the loads light (3.6 grns of Clays, under a cast RN or FMJ-RN 230grn bullet). I've never had a single hiccup until this weekend. During a local IDPA match, I fired a round off and the slide jammed solid at full rear. I tried to tap the slide with the heel of my hand, but to no avail, it was jammed so solidly, it felt like it had been welded to the frame.
Just before this had happened, I had a squib round go off (cast lead bullet) and I had the bullet jam about 1/4 of the way up the barrel. I took my brass rod and light hammer and removed the lead round. I then re-assembled and attempted to get back into the game. First round and then the slide jammed.
I didn't want to play field mechanic, so I packed up the pistol with the slide at full rear and took it home. Once home, I took a really good look at everything and it appeared that the slide was now seizing up against the barrel. I took a set of feeler gauges and tried to fit them between the sides of the barrel and slide. I could do so on top and bottom, but the sides of the barrel were mated solidly to the sides of the slide.
I'm just wondering if a simple squib round and the resulting removal of the lead round could cause the barrel to distort, causing the slide to then seize against the barrel at full back.
It's bad enough that when I rack the slide to chamber a round, the slide jams up and it takes a whack with the heel of the hand to get it to unstick and move forward.
If I shoot a round, forget it, I need to dissasemble the frame to get the slide released. I don't want to hit the slide to make it go, I don't know how much force it would take and I'd prefer to send it back for warranty. Just wondering if anyone else has seen this? If removing a bullet can bulge the barrel, that seems really underdesigned.
Any input?

Cheers,

E

 

[Geno44]

Is there any chance that any of the bullets you loaded were slightly oversized? A couple or three thousandths oversize could cause high pressure even with a light load and bulge the barrel. Can you caliper or mike the outside diameter of the barrel all the way from one end to the other (in many places) to detect a possible bulge? Sometimes you can see a bulge looking down the barrel. Sometimes you can actually feel it on the outside with your hand. Good luck!

 

[S&WIowegan]

My first guess is a damaged recoil spring but not sure how it could have happened. It is still in the gun, right?

I'm not being a wisea**....sometimes the simple answer is the right one.

 

[Wee Hooker]

Have you mic'ed the barrel exterior? From here,sounds like you buldged it with the squib/follow up. That would leave the bushing binding in the "fat" spot where the bullet lodged.

 

[elton01]

Well, I mic'd the barrel down the length. My measurements were .607 at end of muzzle .608 at 3 measurements down the next 1/4 inch, then going to .609-610 for 1.5 inches and finally to .612 for the remainder.

Without another barrel to compare to, I can't be sure if it's bulged or not. When I hold it to the light and look down the side, it looks as if there is just a touch of waviness right where the slide stops. That could be a bulge, which would explain the slide jamming.

It's under warranty, so I'll send back to S&W and let them make the call. I hope that it can be repaired/replaced. I love the gun, it shoots like a dream and is accurate as anything else I've shot from team G.

I checked the recoil spring as well, it looks like it's ok. Thanks for the tip as well, sometimes the best thing to check is the easiest.

Cheers,

E

 

[Geno44]

I'm not sure how Smith will view the warranty if you have been shooting handloads. Often there is some clause in the owner's manual voiding the warranty if handloads are used. (I shoot almost all handloads)

 

[M29since14]

I thought about the recoil spring, too. In 1911s, that can sometimes be a problem - particularly if the evil "shock-buff" has been installed.

I don't have my M&P45 handy but I can't imagine that the OD of your barrel should increase at all as you measure it progressing away from the muzzle. Doesn't sound right. I think you are going to be needing a new barrel, if that is the case.

Rather than just ordering a new barrel, you might consider sending the gun in and asking S&W to check it over. Your "warranty" was nixed by your use of handloaded ammo, but S&W may take pity on you and help you out, even though they are not obligated to do so. If you have damaged your barrel, I would want to be sure the rest of the gun is OK before spending the money on the new one.

 

[BIGMAC116]

I just fixed a co-worker's Glock that had all the same symptoms. The squib round damaged your barrel. My guess is that the barrel is bulged and won't allow the slide to return to battery. Picture Bugs Bunny cartoons back in the day when he'd stick his finger in the muzzle of Elmer Fud's riffle and it would bulge and blow up in Fud's face (although not so dramatic). Hopefully all you need is a new barrel. Watch out for +P and reloaded ammo.

 

[BIGMAC116]

Also: when I removed my co-worker's Glock barrel, the bulge was invisible to the naked eye. But that's all it took to prevent the barrel to fit properly through the slide. $104 Lone Wolf barrel later, the Glock is as good as new.

 

[elton01]

Yep, I've come to the conclusion that I've possibly bulged the barrel at the point where slide is sticking. It has been sent into S&W for inspection. I've indicated that I've been using hand loads. We'll see what happens.
I mic'd all of my cast bullets, and they're all within .451-.452 range. I mic'd the cast bullets I bought from **** Win (a local supplier), guess what, I found 32 rounds in a box of 250 that were .455-.456. This might explain why my barrel has bulged. I thought I'd save my time and just buy cast, meanwhile it may have cost me more than I saved.
When casting my own, I took the time to measure and double check all the rounds. It's apparent that not all casters do the same.
Oh well, if this is fixed under warranty, you can bet dollars to donuts that the only bullets finding their way into my pistols will be factory or ones that I've cast myself. As a matter of fact, I may take the whole 1500 rounds I have purchased of the current .40 and .45 and just melt em down and recast my own. Lesson learnt, mic all bullets you buy to ensure they're good to go, don't assume.

Thanks guys,

E

 

[catcus-jack]

I am going to say you had a squib load on the first shot and then fired another one behind it forcing the first one out and leaving the second one in the bbl.I don't think its a casting problem more a loading problem.

 

[BlueOvalBandit]

Shooting oversized lead bullets such as the .455-.456 shouldn't bulge the barrel(I'm surprised they'd even chamber). I shoot .358 bullets out of a 38 super(.355 barrel), they just swage down. Oversized bullets run into problems chambering.

 

[M29since14]

Elton01, I am inclined to think Cactus-Jack is on the right track. Seems like the only thing that makes sense. An oversize lead bullet like you describe should not cause a barrel to bulge.

I applaud you for being honest with S&W. Whatever happened I doubt very much it is their fault. If they help you out, it would be great CS, but if not, let's hope nothing but the barrel is damaged. Factory barrels are not too expensive. Let us know how this all works out.

 

[elton01]

After thinking about sequence of events, it is possible that there was a squib followed by second round that caused the bulge. I was in the middle of a stage and had others firing at other stages. I may just have missed it and been concetrating on the target and not realized I didn't get the round off. Which is not something I like to admit.
We'll see, the factory barrel is only 139.00
I may replace it with a Storm Lake while it's out, might as well upgrade if I need a new barrel.
If S&W replace it then yep, my pistols will all be S&W in the future because it certainly will be a case of going above and beyond requirements. If not, then hey, I'll have an upgrade on the pistol. Put in an APEX kit and it'll kick ***.
Just hope the slide is OK.

 

[elton01]

Well, no warranty work on this kit.

S&W rep said he felt bad about the end result, but it really isn't anything they can control. This is not an issue though, since putting a Storm Lake barrel was in the future anyway, I'll just be doing it a bit sooner than I thought.

The next piece of great news is that I picked up my M&P .40 Pro today and will be shooting it tomorrow. So one door opens, and so does another....can't get any better than that.

 

[B P S]

Sorry to hear they wouldn't cover it.

The only downside to buying another M&P Pistol, is you have to buy another trigger kit to go with it.

Lee