LMT Upper- Need advice

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[ARCHIVED THREAD] - LMT Upper- Need advice

Posted: 10/1/2004 4:21:21 PM EDT

Okay here's the scoop. I've got an LMT 16" M4 barreled upper and a new Bushmaster lower. My dilemna is what kind of bolt carrier group should I put in it?

I have a LMT enhanced carrier and enhanced bolt but I am very hesitant to go with it because of all the controversy around the enhanced carriers. I have read that Colt bolt carrier assemblies are good because of their quality control but don't know where to find them.

What would you do? a) Buy a regular Bushmaster bolt carrier assembly
b) Look for a Colt bolt carrier assembly
c) Put in the LMT enhanced bolt assembly

Posted: 10/1/2004 4:25:50 PM EDT

[#1]

Can't help with the decision, but you can get Colt bolt groups from SAW.

SAW

Posted: 10/1/2004 4:25:59 PM EDT

[#2]

The LMT enhacned bolt is great, I use one with my LMT 14.5".

But the LMT enhanced carrier is finicky for how it is used. I would suggest dumping the carrier and getting a standard carrier. LMT makes a very nice standard carrier. I have almost 1000 rounds of 55gr Q3131A through my LMT 14.5" with LMT enhaced bolt and LMT standard carrier....zero malfs of any kind.

Posted: 10/1/2004 4:28:24 PM EDT

[#3]

Dump the LMT carrier but keep the enhanced bolt - should serve you well and outlast the barrel of the rifle.
HFG

Posted: 10/1/2004 4:28:58 PM EDT

[#4]

Just saw this post in the rifles and uppers section, it explains the carrier problem well:

www.ar15.com/forums/topic.html?b=3&f=12&t=204162

Posted: 10/1/2004 6:01:06 PM EDT

[#5]

Thanks for the info. I gonna look into getting an LMT standard carrier.

Posted: 10/1/2004 6:56:37 PM EDT

[#6]

What's wrong with the LMT carrier? Don't have one, just curious.

Posted: 10/1/2004 7:10:25 PM EDT

[#7]

i have the LMT enhanced bolt and standard carrier. It has been 100% reliable so far, no malfunctions of any kind. I've only shot a few hundred rounds tho. I have shot q3131a and fed american eagle with it....

Posted: 10/1/2004 7:20:19 PM EDT

[#8]

RRA enhanced carrier or a Colt M16 carrier. Either using a Wolff XP M4 extractor spring.

Posted: 10/1/2004 7:33:21 PM EDT

[#9]

I think RRA bolt groups are GREAT, especially for the price. I have one in my SHTF weapon, and it has yet to let me down

Posted: 10/3/2004 10:03:56 AM EDT

[#10]

I had big problems with the LMT enhanced. Go with Colt. You will save money and have a more reliable weapon.

Posted: 10/3/2004 10:15:06 AM EDT

[#11]

Does LMT make a semi carrier? Or are the enhanced and standard available in both semi and auto?

Posted: 10/3/2004 11:33:07 AM EDT

[#12]

Quoted:
Does LMT make a semi carrier? Or are the enhanced and standard available in both semi and auto?

They make all of them.
HFG

Posted: 10/3/2004 12:40:40 PM EDT

[#13]

Quoted:
I think RRA bolt groups are GREAT, especially for the price. I have one in my SHTF weapon, and it has yet to let me down

+1. I have their pre-enhanced ones and it has been great. I'd like to pick up an enhanced one sometime as an extra.

Posted: 10/3/2004 12:47:26 PM EDT

[#14]

I bought a new Bushmaster bolt carrier group for my new LMT upper and it works great.

Posted: 10/3/2004 2:20:37 PM EDT

[#15]

I'm running the LMT Enhanced Bolt in my MRP (18") with no problems.

-z

Posted: 10/3/2004 3:03:33 PM EDT

[#16]

I'm using the standard LMT carrier and bolt with my upper and so far it's been 100%. What are the benifits of the enhanced bolt? It seems like a solution to a problem that doesn't exist. Enlighten me.

Posted: 10/3/2004 4:11:50 PM EDT

[#17]

Quoted:
I'm using the standard LMT carrier and bolt with my upper and so far it's been 100%. What are the benifits of the enhanced bolt? It seems like a solution to a problem that doesn't exist. Enlighten me.

Posted: 10/3/2004 7:41:43 PM EDT

[#18]

Quoted:
Quoted:
I'm using the standard LMT carrier and bolt with my upper and so far it's been 100%. What are the benifits of the enhanced bolt? It seems like a solution to a problem that doesn't exist. Enlighten me.

photos.imageevent.com/smglee/mstn/large/LMTbolt-3.JPG

Doesn't really answer my question. I like the chrome plating but you can have that with a standard bolt. All I see are two smaller extractor springs instead of one big one and some weird notches on the lugs. Seems to me if parts were to fail you would have a lot more trouble finding new springs and an extractor claw. Can someone please explain the so-called enhancement this thing provides over the standard bolt? Thanks.

Posted: 10/4/2004 4:33:33 AM EDT

[#19]

The locking lugs are rounded and have reliefs in them to help with dissapating sand or grime. With those reliefs in the lugs, the dirt has somewhere to go rather than jamming the operation up.

Instead of relying on just one extracter spring, you have 2 with the LMT. There is also a relief cut on the underside of the extracter itself, but I forget what purpose that served. The whole extractor part is beefier than the std bolt's.

Then you have the wonderfuly smooth chrome finish, makes cleaning a joy.
I know I'm missing something else, but that's all I remember off the top of my head.

Posted: 10/4/2004 5:23:18 AM EDT

[#20]

Quoted:
The locking lugs are rounded and have reliefs in them to help with dissapating sand or grime. With those reliefs in the lugs, the dirt has somewhere to go rather than jamming the operation up.

Instead of relying on just one extracter spring, you have 2 with the LMT. There is also a relief cut on the underside of the extracter itself, but I forget what purpose that served. The whole extractor part is beefier than the std bolt's.

Then you have the wonderfuly smooth chrome finish, makes cleaning a joy.
I know I'm missing something else, but that's all I remember off the top of my head.

The reliefs actually reduce the stress on the root of the lug - any dirt clearing is purely coincidental - by shortening the moment arm, the lug acts as a spring and prevents the stresses at peak pressure, transferring to the root and fatiguing it (that's the theory anyway). The bolt is electroless nickel plated, which makes cleaning easier and does add some lubricity, the cut outs on the underside of the extractor allow for more material in this part but allow it to grip the cartridge rim.
HFG

Posted: 10/4/2004 5:36:19 AM EDT

[#21]

Thanks for the correction HFG, I didn't realize that.

I just know mine works great.

[ARCHIVED THREAD] - LMT Upper- Need advice

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