BCM/LMT first stoppage ~600 rounds

[futureAT]

Had my first stoppage yesterday.. I have fired probably 600 rounds through this since I built it (no assembly myself, just parts put together) with zero problems up to this point. The last cleaning was ~300 rounds ago with about a month between firings.

Specs:
BCM BFH LW middy upper
LMT "enhanced" bolt/standard F/A carrier
LMT lower receiver/ 2-stage factory trigger
I was shooting black hills soft point 62 gr

I was firing strong side with the rifle turned on it's side, ejection port facing up, shooting over a berm when I had a stoppage. I looked into the ejection port and noticed that there was a cartridge sticking about 1/2 way out of the chamber and the bolt was pressed up against the rear of the case but the cartridge was not inside the bolt face (extractor couldn't grab it). I tried racking it several times but the casing was lodged pretty tightly, so I stopped the drill and took it to the truck. Since the bolt wouldn't grab the case, I just held the charging handle rearward and tapped the rifle on the ground buttstock first and this is what came out after a few whacks (see attached).

It looks like it fired the round, ripped the case in half inside the chamber, ejected the rear half, leaving the bullet half of the case lodged in the chamber, and loaded the next round into it. Didn't find the other half.. I sprayed some oil on all the main parts, reassembled, and didn't have another hiccup in the 100+ rounds I fired afterwards.

Ideas? I built this rifle with the highest quality of parts I could afford, reason being is because I wanted to avoid these problems..

11573

11574

11575

11576

[Failure2Stop]

It's a cartridge case failure.
It happens.
Drive on.

[futureAT]

Thanks F2S. Figured that's what it was, just surprised me since I almost exclusively shoot black hills. First encounter for me! Glad it wasn't on a 2 way range..

[Failure2Stop]

Happens a lot with M249s even though they're using LC brass.
It's just one of those things, and usually the second round pulls out the broken top half. However, it's not a bad idea to have a broken shell extractor on hand.

[CoryCop25]

However, it's not a bad idea to have a broken shell extractor on hand.

do these things really work? I have been told they are a waste of money.

[MistWolf]

Looks like that case was reloaded once too many times

[Failure2Stop]

do these things really work? I have been told they are a waste of money.

I've only used the 7.62 ones in real life.
The 5.56 occurrences have always pulled out with the live squished round, so I've never had to use one.

[rob_s]

blue box or red box?

[Sgt_Gold]

blue box or red box?

It would have to be blue box, red box is all now components. Brass out of an M249 is already stretched pretty badly and has a known history of higher than normal case head separations.

[globeguy]

blue box or red box?

I hope blue box. :eek:

[TehLlama]

It could well be red box - case separation failures do happen, they're obviously uncommon, but I've had one in an M16 before with LC brass too.

[kartoffel]

If you extractor started making a habit of ripping the rims off cartridges, I would worry. However, that looks like a textbook case head separation. It's more likely to be bad brass, rather than a problem with the gun.

[QuietShootr]

do these things really work? I have been told they are a waste of money.

Yep, they do, and if you don't have one when you need one you're pretty much SOL. 5.56s sometimes come out just the way the OPs did, but bigger ones rarely work like that.

[Robb Jensen]

I've had it do that at least 20 times with blue box.

[Nightvisionary]

Why are there concave grooves in the top of the bolt lugs?

[militarymoron]

Why are there concave grooves in the top of the bolt lugs?
it's LMT's enhanced bolt.

[Heavy Metal]

It's your practice ammo, don't sweat it!.

BTW, this is the EXACT reason BH DOES NOT recommend Blue Box ammo for self-defense or duty use! Training use only!

[Nightvisionary]

it's LMT's enhanced bolt.

I read that so I went to the LMT site to look at the enhanced bolt. The one shown on their website does not have grooves. If it's suppose to be that way I wonder why. It seem like more surface on a locking lug would be better than less.

This is the LMT enhanced bolt from their website.

http://i43.tinypic.com/35bzbmg.jpg

[Clint]

5.56s sometimes come out just the way the OPs did, but bigger ones rarely work like that.

The 7.62 case has less body taper than 5.56.

Possibly related.

[futureAT]

I apologize for the delayed response fellas. Thanks for the feedback. I was shooting blue box at the time as I shoot it regularly and I was not aware that they recommended blue box for training only.. I'd say I've shot nearly 2,000 rounds of it, no problem; but I'll definitely be purchasing some more trustworthy ammo to load up my go-to mags with. I know the drill: orange search button..

Thanks for the knowledge contributed everyone! Much appreciated. Stay safe.

[Failure2Stop]

I read that so I went to the LMT site to look at the enhanced bolt. The one shown on their website does not have grooves. If it's suppose to be that way I wonder why. It seem like more surface on a locking lug would be better than less.

This is the LMT enhanced bolt from their website.

http://i43.tinypic.com/35bzbmg.jpg

Must be a new design.
http://www.google.com/search?q=lmt+enhanced+bolt&hl=en&rls=com.microsoft:en-us:IE-SearchBox&rlz=1I7SMSN_en&prmd=imvnsfd&source=lnms&tbm=isch&ei=0C5oT66LDMX-sQKu7dWQCQ&sa=X&oi=mode_link&ct=mode&cd=2&ved=0CA8Q_AUoAQ&biw=1366&bih=673

[JEL458]

do these things really work? I have been told they are a waste of money.

I used a 5.56 one several times in a TRICON class a few years back. It worked as advertised. The Team that was in the class was using cheap reloads.

[GunTotinRedneck]

And that happened with Black Hills ammo? Geeze... :confused: