LMT MRP CQB Piston Middy or LWRC Piston?

AR/M4 AR Technical Discussion
1

Which one should I get. I already have a DD M4 and I am looking for a piston.

Options:

LMT MRP CQB middy with Sopmod stock for $1599

LWRC M6 A2 in FDE for $1935

LWRC M6 A1 middy Paul Howe edition with whole package for $2160

These are all new gun prices.

Positives and negatives of the LMT vs LWRC?

Also, any problems with either?

I have read some on both, but never a head to head comparison.

Thnx

2

I have a LWRC M6 A2 with MRE finish and can tell you that they are great guns. Fit and finish is the best I’ve ever seen on an AR-15. That said LMT’s are great weapons as well.

3

I own both LMT and LWRCi for sometime now and found the LMT to be slightly ahead of the LWRCi in the following: Accuracy, ease of cleaning, and being able to change barrel on your own.
Also, LWRCi has a sharper recoil which isnt much on a 223 but it is noticeable between the two,

4

Correct me if Im wrong, but cant you change the MRP piston to DI and vice versa? I would go with the LMT personally, I had an LWRC M6A2 until this week. Wasnt a fan of the balance of it at all.

5

GMZ is right about the balance between the two…LMT wins hands down.

6

The comments on balance are pretty accurate. I owned both and found the LWRC M6A2 to be noticeably more heavy up front than the LMT. The LMT is also easier to clean as taking out the piston is incredibly simple.

7

Two rifles that I can never get rid of are my Sig 552 Commando (556 conversion) and my LMT MRP Piston M4. The piston is way easier to get to for cleaning and you can change barrel lengths in mins as well. :cool:

8

I own uppers of both in question. They are both excellent and you do get alot for your money, especially with LWRC. I personally can’t decide which is better since both have their own strengths and weaknesses. I did a comparison on an old thread listing pros and cons of both. I hope this will help you…

LWRC M6A2

PROS

  • 1/7 cold hammer forged ferritic nitrocarburized barrel
  • Slick full-auto Teflon Nickel BCG with raised grooves
  • Comes with Troy front and rear BUIS
  • Well designed piston system, low profile
  • Top rail is continuous with flat-top, no loss of zero in my experience when taken off for cleaning then placed back on
  • Excellent CS

CONS

  • Expensive
  • Top rail must be removed to access the piston
  • 3 piece piston can be a bitch to remove
  • Rail could be longer (there is the M6A2-S if you want a longer rail)
  • Gas pushed out of piston cup gets all over the front sight and anything else attached near the cup’s location
  • Mine came with the older two-piece BCG, and the staking job does not look GTG to me. I plan to get the new one piece soon (Not an issue anymore since they come with new flat face BCG now)
  • Yes it is front heavier

LMT MRP Piston

PROS

  • Monolithic rail
  • Quick change barrel & gas system capability provides unmatched versatility
  • 2 piece piston is easily removed from the front
  • Comes with LMT’s Tactical latch charging handle
  • BCG is one piece, has O ring insert and like all LMT products, well-made
  • Lighter
  • Less expensive
  • Excellent CS

CONS

  • (I used to list current availability since it took a year to get mine but now they seem to be more available.)
  • Came with semi-auto BCG (LMT doesn’t sell F/A BCGs to non-LE/mil contracts?)
  • Does not come with BUIS
  • Very tight fit (emailed LMT and they said they purposely machined them for a tight fit. It fits my KD lower with some effort but does not want to close down on my Daniel Defense lower. I guess this will appeal to the “fit and finish” crowd :rolleyes:)
9

I can second this. I put the LMT piston upper on 2 different lowers, both Colt, and it was ridiculously tight. I needed a flathead screwdriver to remove both pins.