Hi all,

I am building a LMT MRP CQB with the CL 16" barrel. Upper/stock should be here tomorrow.

I ordered their M4 Stock Assembly with the upper. First does anyone know if the assembly comes with the buffer and buffer spring?

Second if it doesn't should I go with LMT's Heavy Carbine Buffer (item # L7CB2F) or should I stick with a standard carbine buffer? I will be shooting a wide variety of ammo through this upper. Everything from 55-77gr bullets. Maybe lighter than 55 it it will shot them OK.

I am after the BEST in reliability and want to make sure everything is right.

That's it for now.

Thanks!

If you ordered the $58 stock assembly that would only be the stock, no tube or hardware, the $128 assembly includes tube and hardware but doesn't mention buffer and spring per LMT's site.

I had better luck with the LMT H buffer with my standard LMT 16" Defender 2000 carbine setup with LMT M16 BCG and I'm also using some extra power magazine springs on some of my mags.

The standard LMT carbine buffer have no markings but their H buffer have a letter H marking on the front face of it.

I would also highly recommend the BCM extractor spring upgrade kit from Bravo Company, it have a better extra power chrome silicone 5 coil springs, black buffer insert and Crane O-ring which in my opinion required on all carbine gas systems.

Quoted: If you ordered the $58 stock assembly that would only be the stock, no tube or hardware, the $128 assembly includes tube and hardware but doesn't mention buffer and spring per LMT's site. I had better luck with the LMT H buffer with my standard LMT 16" Defender 2000 carbine setup with LMT M16 BCG and I'm also using some extra power magazine springs on some of my mags. The standard LMT carbine buffer have no markings but their H buffer have a letter H marking on the front face of it. I would also highly recommend the BCM extractor spring upgrade kit from Bravo Company, it have a better extra power chrome silicone 5 coil springs, black buffer insert and Crane O-ring which in my opinion required on all carbine gas systems.

I ordered the stock with all the hardware.  Yes their site says nothing about the spring and buffer.  I assume I am going to have to call them tomorrow and get it ordered.  

When you said you had better luck with the H Buffer, what exactly has it done for you compared to the standard buffer?  My MRP upper is the 16" barrel with the mid-length gas system.  Do you think I will benefit from using the H Buffer still?

My upper is coming with the standard LMT M16 BCG.  I thought that the LMT M16 BCG came with the 5 coil spring and the black buffer insert with the o-ring.  If not I will be ordering the upgrade kit from Bravo Co.  I have a couple Bravo Co. BCGs in other ARs and they are top notch!  I believe they did come with the black buffer insert with the correct spring.

Sorry if my response seems choppy.  I am recovering from knee surgery Fri and I am pretty doped up on pain meds at the moment.  I just want to make sure I understand what you are saying before I order anything tomorrow!

Thanks

My MRP is sitting on a LMT Defender lower ordered with SOPMOD stock and 2-stage trigger. This lower came with the standard (not heavy) buffer and the MRP is utterly reliable with all kinds of ammo.

I have tried heavy buffers and pneumatic buffers in other lowers with the MRP and it seemed finicky with heavy buffers, not working well with some ammo. I haven't had any problems with the LMT lower with the standard buffer. IMHO you should get a standard buffer. You could always experiment around based on your own ammo preferences. I have been shooting 62 gr Wolf and 69/77 SMK reloads.

For midlength gas system the standard carbine buffer would work just fine.

I also have a midlength gas system Denny's Guns Operator 16" barrel on my Colt 6721 carbine and it works great with my Vltor standard carbine buffer.

I would only recommend the H buffer (or heavier buffer) for carbine gas systems, midlength and rifle gas systems are fine with standard buffers.

My two LMT M16 BCG didn't came with extra power 5 coil extractor springs, it had the standard Mil-spec 4 coil springs (maybe stainless), I just upgraded them with BCM extractor kit's extra power chrome silicone springs and I'm very satisfied with them.

Quoted: My MRP is sitting on a LMT Defender lower ordered with SOPMOD stock and 2-stage trigger. This lower came with the standard (not heavy) buffer and the MRP is utterly reliable with all kinds of ammo. I have tried heavy buffers and pneumatic buffers in other lowers with the MRP and it seemed finicky with heavy buffers, not working well with some ammo. I haven't had any problems with the LMT lower with the standard buffer. IMHO you should get a standard buffer. You could always experiment around based on your own ammo preferences. I have been shooting 62 gr Wolf and 69/77 SMK reloads.

I probably just stick with the standard buffer.  Who knows maybe the buffer spring and buffer will be included in the assembly.  I guess I'll find out tomorrow.

BTW how do you like your LMT 2 stage trigger?  I ordered one of those as well.

I am really looking forward to my build tomorrow.  After doing much research on the MRP, I know I will be happy.  I am putting the upper on a Tactical Innovations T15BDX "Deluxe" billet machined lower

Quoted: For midlength gas system the standard carbine buffer would work just fine. I also have a midlength gas system Denny's Guns Operator 16" barrel on my Colt 6721 carbine and it works great with my Vltor standard carbine buffer. I would only recommend the H buffer (or heavier buffer) for carbine gas systems, midlength and rifle gas systems are fine with standard buffers. My two LMT M16 BCG didn't came with extra power 5 coil extractor springs, it had the standard Mil-spec 4 coil springs (maybe stainless), I just upgraded them with BCM extractor kit's extra power chrome silicone springs and I'm very satisfied with them.

Sounds good.  I need to place an order with Bravo so the timing is right!  Thanks for your advice.

I like the LMT 2-stage. It has a "long" first stage which takes a little getting used to, but the 2nd stage break is very crisp. It's the best of the 3 2-stages I have (the other two are the Bushmaster and RRA), and the time to get it is when you buy the receiver. I think they only bump the price by $74 over their standard trigger, and this is a bargain for a factory installed EXCELLENT 2 stage trigger. If you upgraded to some other match 2-stage later, it will cost you more (possibly MUCH more) especially if you are going to have some one else do the installation.

I usually favor a single-stage for most of my shooting, but yesterday I was shooting at a "swinging" target - and appreciated being behind a 2-stage trigger.

You should remember to lube the FCG before you first use it. My LMT lower came out of the box pretty "dry" and needed lube prior to first shooting. This includes the sear. IMHO the MRP CQB is "happier" with the Defender lower than with any of the other lowers it's been used with (Colt, Bushmaster X2). Almost as if the CQB was designed o be used with the LMT Defender/SOPMOD lower...