LMT MRP Rifle length

[sf88]

So I just picked up an MRP rifle length with an 18" SS barrel at a sweeeet price, but I originally wanted a 16" to make it more of a recce style with the long rail. If I cut the barrel do I need to mod the gas port? Not sure what length the gas system is. Also, bother cutting the barrel or leave it be? My original plan was for a 16" SS with a 1-4 optic.

ETA: This is going to be my ONLY ar for quite a while, keeping my scar and this as my only carbines. I'd like for this to be as broad as possible in terms of capabilities, but I had to go stainless since accuracy is #1 for me.

 

[trident1982]

Re: LMT MRP Rifle length

Congrats, I never looked back once I got my first stretch chassis.

I certainly wouldn't chop the Rock 5R SS barrel, I would either keep it as is, or sell for the one you want.

Both barrels in question are mid lengths and should have the same gas port fwiw.

Personally I think you need both

 

[mattmcg]

Re: LMT MRP Rifle length

I second what trident says. Don't cut it. Just sell it and buy the one you want.

I unfortunately only have chrome lined 16" extra MRP barrels otherwise I would trade you.

 

[HPLLC]

Re: LMT MRP Rifle length

If the Stainless barrels are anything like the 16" CL barrels, you will be able to cut it without other mods.

The CL barrel users are reporting overgassed guns. The stock buffer is an H3 carbine buffer 5.6 ounces. So if you chopped and re-threaded it to 16" and had issues with gas, you could rectify them by just swapping to an H2 buffer or H buffer. The solutions for under-gassing are a lot more simple than for over gassing as the heaviest buffers on the market are ~7.1 ounces (MGI RRB)

ADCO firearms in Ohio does very nice thread work and has fast like 1-2 week turnaround.

18" might be the ideal OAL. The 16" guns are getting 2500FPS with 45grains of Varget and 175Grain loads. It would be nice to be able to back off to 44 or so and still hit 2500FPS.

I have a 16" CL coming and I'm going to run 45grains of powder in it because I want to get that velocity. I also would do a trade + cash for a Stainless 18" barrel. I would have bought a SS barrel, but the $700 price tag is kind of outrageous IMO.

 

[trident1982]

Re: LMT MRP Rifle length

Were talking MRPs not MWSs homie

 

[sf88]

Re: LMT MRP Rifle length

I'm going to take Trident's advice and just wait until I can afford a separate 16". I can probably get together the scratch for a shorter general purpose upper right now if I sell an unused eotech or something similar.