LMT Piston Barrel Accuracy?

Glassaholic

Optical theorist and conjecturer
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  • Nov 30, 2012
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    Back in the early 2000's I bought an LMT rifle with a 16" piston barrel that had accuracy issues (2 -3 moa at 100 yards doesn't cut it for me). I know LMT has made great strides over the past two decades but am curious if anyone has any of their new piston uppers and what kind of accuracy you're getting with match grade 5.56 ammo? I would like to be able to ring steel out to 600 yards with this setup and I like piston uppers because I almost always shoot suppressed and pistons are a lot cleaner than DI; however, if by going piston means I'll sacrifice accuracy then I'll just deal with the carbon build up and stick with DI.
     
    I think general quality issues are the gremlin at LMT right now regardless of the barrel type more so than any systemic deficiency in accuracy. Folks I know have been happy with accuracy, but reaming your own chamber isn’t unheard of.
     
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    Back in the early 2000's I bought an LMT rifle with a 16" piston barrel that had accuracy issues (2 -3 moa at 100 yards doesn't cut it for me). I know LMT has made great strides over the past two decades but am curious if anyone has any of their new piston uppers and what kind of accuracy you're getting with match grade 5.56 ammo? I would like to be able to ring steel out to 600 yards with this setup and I like piston uppers because I almost always shoot suppressed and pistons are a lot cleaner than DI; however, if by going piston means I'll sacrifice accuracy then I'll just deal with the carbon build up and stick with DI.
    Great question as I was looking at the piston LMT myself. Just bought a MK116 and am liking the piston system, so was looking to add another. Might just go with the SCAR 16. Curious to see what others have to say.

    My MARS-H has been awesome, but its DI
     
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    I had a similar problem with Federal GM 168gr. Tried the Federal GM 175 and it was better. I don't know if that's a common result but it might be worth a try.

    John McQuay (perhaps 8541 Tactical?) Had a couple of threads where he went down the rabbit hole after LMT MWS accuracy.
     
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    I have a 2 week old MARS-L piston and it shoots sub MOA with 62gr green tips with only a couple hundred round down range. So far so good. I hope so, as I just ordered a MARS-H piston and it was not cheap. Fingers crossed.

    On that topic, anyone aware of an aftermarket 6.5 creed piston barrel for the MARS-H?
     
    Problem with 62gr M855 and SS109 is the steel penetrator under the jacket and concentricity. It’s hard to get mass-produced military ammo like that to be made precisely. Sectioned samples of M855, M855A1, and M995 AP:

    greenm85541215-002-zpscvot6dyb.jpg