I’ve considered many different rifles lately and have finally narrowed it to another M4. My main question is the enhanced BCG from LMT, specifically their dual extractor spring bolts. Is there any advantage in this? Otherwise I will probably get the Colt.
BTW, good site, good people, good info. Thanks
I think I’ve asked this question before; A simple answer would be to buy a Colt LE6920 and put a Crane Reliability O-Ring/Stud/Extractor spring Kit into the bolt.
Grant sells them…
Also, IMHO, the LMT Enhanced Bolt is an example of fixing something that isn’t broken.
Flip a coin. Cant go wrong either way
I’ve got both Colt and LMT but I’m a long time Colt user and they’re both fine.
I have the regular LMT M16 BCG on my LMT carbine with an upgraded extractor spring and it works well, I’ve heard mixed reviews about the enhanced LMT BCG.
Both of them have a good amount of Mil-spec features but there’s a few little differences like the LMT have non tapered FSB pins, bottom of FSB sling swivels, not parkerized under the FSB, single layer heat shields handguards, standard carbine buffer, and six position buttstock.
Colt have tapered FSB pins, parked under the FSB, barrel side sling swivel, double layer heat shields handguards, H buffer, four position buttstock, and large diameter FCG pins.
I would suggest to pick the brand which have the features that are important to you.
The LMT Enhanced BCG was designed for a very specific purpose. It is intended for carbine length systems with to much port pressure. If you don’t have a 14.5" or 16" carbine length system with too much port pressure it’s a liability as it will slow the gun down. You can use the enhanced bolt in a standard carrier and have no problems but I don’t think there really is a point.
The LMT enhanced carrier is an excellent upgrade to 14.5" and 16" carbine-gassed barrels due to it’s re-timed cam slot which allows extra time for the bullet to leave the barrel and the case to shrink back down to original size.
This makes for more reliable extraction and a cleaner running gun.
The dual extractor bolt is nice as well, but it’s not enough better than a good standard bolt to justify the extra cost in my opinion.
Go Colt or LMT, won’t matter.
Put the LMT enhanced carrier in the upper if you want it to run cleaner and more reliably.
They now come with the 5coil spring, black insert and Oring from the factory.
THe handguards are a add on item and dont come standard with the upper.
Yes, I’m aware that the handguards are an added item when you buy a LMT upper, but the OP is buying a complete carbine and complete LMT carbines are available now, see the G&R Tactical website. 
In addition to the handguards, the BCG, CH, and BUIS are also added items on separate LMT uppers.
When I bought my LMT upper and lower separately a couple of years ago, I got the handguards and CH plus free shipping as part of the upper deal. 
The guy in TOS that sells the uppers and includes the handguards isnt giving LMT handguards with it. Im not sure if thats who you got it from.
Get both or a combination of both. Here’s my LMT 14.5" brought “up to spec” :D:
Colt 4-position receiver extension with Colt CAR stock and H buffer. Colt detachable carry handle, Colt side sling swivel adapter and Diemaco M16 BCG.
LMT handguards would not be my first choice.
They are M4 size, but only have single heat shields.
If I’m only going to have single heatshields, I don’t want the fat handguards.
As backwards as this sounds, I recommend the Rock River R4 handguards with dual heat shields over the single heat shield LMT’s.
It doesn’t hurt that the RRA R4 handguards are $15 less expensive to boot.
Agreed
I love it.
my LMT upper came with everything but the BUIS.
I paid the 38 bucks because I wanted all LMT parts
The LMT M4 HG work Fine here in Punta Gorda FL
It gets real hot here in SWFL and my hands are fine
Other than that I like KAC RAS even better
I have a Complete Defender 2000 M4 14.5
and as a SPARE Bushy/VLTOR lower with LMT M4 upper
Both have arms BUIS
I dont like LMT buis at all
Why not?
I have a Complete Defender 2000 M4 14.5
and as a SPARE Bushy/VLTOR lower with LMT M4 upper
Both have arms BUIS
I dont like LMT buis at all
yeah,i just bought a YHM A2 flip up for mine.
i like it fine,but might get something else down the road.
I highly recommend the Larue BUIS.