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  #1  
Unread 04-03-09, 22:00
mechelaar Offline
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LMT Lower issues?

I recently purchased a LMT complete lower. The lower has not yet been fired, but I did slap an upper on it to make sure everything was working. I’ve noticed a few issues that I have not noticed with any of the other lowers I’ve dealt with/owned (RRAs, LWRC, and USGI Colts). I’m starting to worry I got a bad or slightly out of spec lower.

First, the mag well is a little tight. Closer inspection of the mag well reveals several slightly raised rough spots where the finish is starting to flake off. Pmags (with the exception of one old one) will not drop. USGI and H&K mags drop fine. I'm not sure if the pmags are hanging on the rough spots in the mag well, but I feel like the finish should not be chipping on a new lower.

The second issue is that it seems to have an unreliable “two stage” bolt catch/release. The bolt does not always lock back on an empty chamber when the charging handle is pulled. After removing the upper, I noticed that something with the bolt catch is hanging, preventing the mag follower from lifting it. This mostly happens with pmags. As far as the "two stage"-ness, when I try to release the bolt with a magazine in, the bolt catch creeps and hangs a little before finally dropping the bolt. It feels like the release somehow is hanging on the mag, but I can’t really see what’s going on. This happens with all mags. I suspect the two issues are related

Also, unless you flick the thing pretty good, the safety selector will sometimes hang between safe and fire. Not as much snap to it as I'm used to. Maybe a weak spring? Not a major issue, but I thought I'd mention it.

Anyway, like I said, I’ve never really run into these issues before, even with a brand new lower. I was wondering what you guys thought. Does this sound like an RMA or does the lower just need some break in? I’m not sure what to do here.

edited to make more sense

Last edited by mechelaar; 04-04-09 at 04:40
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  #2  
Unread 04-03-09, 22:46
Thomas M-4's Avatar
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I have a lmt upper and lower and i was having issues with the bolt catch not locking the bolt back on the last shot all of the time. The bolt catch spring seem to be a little stiffer than what i thought it should be. I hosed it out with gun scrubber real good and worked the bolt catch by hand for about 30 mins reoiled it and stuck an empty mag in it over night with the upper off after that seemed to help a little.
but i tried brownells mags HK mags and my bolt was only locking back about 30%to 40% of the time. I found some p-mags and the next trip to the range it worked perfect locked the bolt back every time I still need to test some more but I am pretty sure that fixed it .
The first time i put a p-mag in my lower it didnt drop free but after the third time me doing empty mag changes it drops free now and the 4 other p-mags drop free no problem.
Are you sure the finish is comming off or is it the dry film lubricant from the mags just rubbing off into the magwell?
I hope this helps
ymmv
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  #3  
Unread 04-03-09, 23:18
mechelaar Offline
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I tried to take some pictures, but I only have my phone camera at the moment. In the first picture, I tried to circle the bare metal spots, but it is really too blurry to see. I scrubbed at them a little bit with some lube and then scratched at them with a fingernail. More finish came off. It is definitely bare metal.

In the second picture the bolt release paddle is pressed in and stuck on an empty magazine. If I let it sit like that, it will pop back out on its own after about a minute. In the third picture, you should be able to see the bolt catch on an empty magazine as it should be. The hammer is back on both pictures.




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Unread 04-03-09, 23:39
Thomas M-4's Avatar
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mine wasnt sticking like you just discribed . It was just a hair stiffer than what i thought it should be.
In my magwell there are streaks from the the dry film lubricant that rubbed off from my mags and scratching it with my fingernails doesnt do anything to them but thats normal but if yours is flaking off i would send it back to lmt everybody says they have good customer service. I have no Idea about the wait time ?

Sorry i cant tell any thing with the pictures

I am sure that some other people can chime in and give you some advise
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  #5  
Unread 04-04-09, 00:18
OneKYards Offline
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I had issues with my lower fitting on the CQB MRP and Standard MRP Uppers. The Uppers have two protrusions close to the front pin/ejection port cover to keep the upper and lower tight.

My Mag well is not a tight fit for USGI, MagPul, or TangoDown's ARC. I did notice the bolt not wanting to release when I hit the release and seemed a little tight. It may be the Young Manufacturing Bolt Carrier Group. Will wait for the LMT BCG to show up.

You should definitely send yours back. Call the LMT's main line and ask for Gene Swanson. He handles warranty and issues with the parts. In the AM, he is out test firing weapos, so you may have to leave a message.
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