A few problems with an LMT upper

AR/M4 AR General Discussion
1

I’ve got an LMT M4 upper half with 30 rounds through it. It is exibhioting afew problems. When feeding (by hand) the bolt is fairly slugish and often does not fully chamber the round. (Yes I am pulling the charging handle fully to the rear and releasing it.) The problem persists with several different mags USGI and P mags. Often when pulling the charging handle to the rear it sticks and takes quite a bit of force to pull it back, this has lessened since it was brand new, but is still noticeable. When firing I had to slam the but of the rifle on the ground to get it to extract more than once. Inserting a round into the chamber by hand with the BCG removed the round tends to stick in the chamber with and not fully seat about half the time. Again this is with several different types of ammo. All problems seem to persist wether the upper is on a lower or not. Ejected rounds all have pretty deap scratches in the projectile and ejected brass has scratches running from the neck to the head. So I’m thinking there is a bur in the chamber though I can not make it out visually. Any other thoughts?

Also there is some premature wear inside the reciever and on the cam pin. the wear may indeed be normal, most of the M16s I dealt with in the service were quite old, however my other ARs never showed this much wear this quickly. I could really care less about the cosmetic issues however I would tyhink it should hold up better than this.

All in all this upper has been a dissapoint ment to date. I’ve owned several other Ars over the years, RRAs, Bushys and other LMTs and never had one that would not feed reliably before. I’ll be calling LMT Monday to see what they can do inless anyone here has an ideas that may fix the problem.

The round on the left shows the typical scratches on the projectile.

The bottom round shows the typical scratches in the brass.

Here’s the best pic I could get of the chamber and feed ramps, not very helpfull I know.

Here are a couple shots of the finish wear I was talking about.

2

Just letting you know my 16" LMT Upper does the same exact thing with the scratches on the brass and bullet.

It has caused no problems to date after 1k rounds.

I also experience the same wear from the charging handle on the top part of the upper. This also hasn’t caused any problems. My bolt has no problem going forwards and backwards though.

I’m assuming you have her lubed up real well right?

3

What does the inside of the chamber look like? Shine a bright light down in there and tell us what you see.

4

the " finish wear" is probably LMT dry lube, the same they put on their buffer tubes

5

Nothing is wrong with your LMT and you should run it a little more wet with oil.

Also following the rules here if you think you have a problem you should contact the manufacturer first.

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