LMT MRP Piston - Carrier Tilt Issues?

AR/M4 AR Technical Discussion
1

I am very interested in getting the LMT MRP defender 16" with the piston system and was wondering if anyone had experience with these. I’m mainly curious about carrier tilt issues. Their website is very uninformative, and I can’t find any decent pictures of the parts. Does the BCG have skids to stop carrier tilt like some do? Or is this just not much of an issue?

Also, is there a standard to the design of piston BCGs like DI ones, or is each one made for a specific system? Say if I wanted to get a BCG that did have skids to prevent carrier tilt, could I use it in the LMT or do I have to use the specific LMT BCG?

Thanks for any information.

2

I only fired 400 rds with mine. So far I only see a very smooth little finish worn in the tube. If it stays that way, it’s a non issue.
Other than that , I’m very pleased with the way it performs.

3

Carrier tilt isn’t a real issue with pistons any more.

Also: No you can’t mix and match BCGs. You have to get piston specific ones.

You can throw any maker’s piston BCGs in a piston gun though, the same way you can with DI.

Like how if I’m running a friend’s Adam Arms piston, LMT piston, or otherwise. I throw one of my spare LWRCi BCG + Bolt group in it. (I have a designated one for this purpose.)

4

This is odd. What LWRC upper do you have? My M6A2 has a “solid” carrier-key, whereas the LMT/Adams Arms has a one-piece carrier with a smaller carrier-key. I think the bolt-carrier itself might be interchangeable but I do not think you can just drop in the BCG and expect all piston guns to be cross-compatible.

5

Earlier LWRCs had a shorter op-rod with Bolt Carriers similar to your standard DI BCG. Problem was the key would still wiggle loose/shear, so LWRC went to a longer op-rod and a one-piece carrier.

6

All current generation LWRCi M6 series rifles share the same bolt carrier.

I have an M6A3 that I bought in January 2010. It has the advanced combat bolt, similar to the KAC E3 bolt. Just not proprietary.

7

Oh really? Have your seen gotM4’s write-up on the Ruger Sr556?

http://m4carbine.net/showthread.php?t=31110&highlight=sr556+ruger&page=16

http://m4carbine.net/showthread.php?t=31110&highlight=sr556+ruger&page=13

8

Maybe I should rephrase…

Carrier tilt isn’t an issue on a well engineered piston rifle.

LMT, LWRCi, H&K, etc.

9

I just received a new Ruger SR556C. After nearly 150 rounds I have no signs of tilt in the buffer tube.

10

I have a 16" LMT piston MRP with Noveske lower. While I do not have thousands of rounds through the rifle yet, I can say that at this time I have had no problems with carrier tilt. Lmt does have ramps to the rear of their carrier to help limit tilt. I also am using the Anti Carrier Tilt Buffer from Firearm Ready Solutions. The Rifle works great and I am very pleased with the performance of the buffer. It’s virtually eliminated any tilt issues. The buffer can be found here by contacting Seth Harness

11

Yes the LMT MRP piston bolt carrier has two skids on the bottom.
After only 20 rounds they start to wear the anodizing away inside the buffer tube.
I know that people say it does not matter, but it bugged me, so I am sticking with DI.

:cool:

12

The action spring in your DI gun will eventually wear through the buffer tube’s anodizing.

13

150 rounds isn’t enough to tell anything. Read gotm4’s write up on the Ruger linked above.

14

I’ve read M4’s opinions on the Ruger. I’ve got another 556 with 4,000 rounds through it. While it does show some wear, it’s nothing I’m concerned about.