Looking to sell my Proof 18" 6mm Arc Upper.
This was my first foray into "accurizing" a gas gun, so it got the full works (steel shim and green loctite) when building, following the advice from the written work of Joe Carlos.
I'm selling this now because I plan on building an almost-identical setup, but in a much shorter barrel length, to shoot suppressed.
Parts list:
I would like $1200 OBO (shipped) for this setup. It has approximately 500 rounds down the pipe.
the full length arca rail handguard by CMT is superb, adding weight and tripod/bipod ideal flexibility. I would consider selling without the Geissele Bolt Carrier, to reduce the price, if necessary. You would still get the headspaced JP Bolt, just need to provide your own carrier (tested with JP FMOS, worked well).
I also tested this on a variety of magazines once I figured out the gas system, and can confirm it works reliably with both grendel mags, and dedicated 6mm arc mags, and will feed from both ASC and duramags without issue.
A few edges on the hand guard have the black paint scratched off near the upper receiver side, I tried to photograph those closely so there's no surprises to the condition. The pic rail on the upper has silver sharpie from the scope mount, which will be removed before shipping. This also clears the superlative arms gasblock (others have asked this before).
I included a few shot groups with hornady black, and chrono data for both hornady black and hornady match.
Pics (scope and mount not for sale, sorry):
hornady black:
horandy match:
This was my first foray into "accurizing" a gas gun, so it got the full works (steel shim and green loctite) when building, following the advice from the written work of Joe Carlos.
I'm selling this now because I plan on building an almost-identical setup, but in a much shorter barrel length, to shoot suppressed.
Parts list:
| part | cost | |
| barrel | Proof 18" stainless steel rifle+1 Barrel | 500 |
| gas tube | Proof rifle + 1 gas tube (their proprietary length) | - |
| upper | VLTOR MUR-1A (with Forward Assist) | 200 |
| handguard | Cross Machine Tool HDM Rail with Full Length Arca, 17" | 237 |
| bolt carrier | Geissele Reliability Enhanced Bolt Carrier | 145 |
| bolt | JP Enterprises Headspaced Grendel Type 2 Bolt DLC (includes one piece and mil spec 3 piece gas rings), verified and headspaced to this barrel, per Proof's recommendation | 150 |
| muzzle device | Nextgen EC Tuner - 6.5 MM | 250 |
| charging handle | Aero Large Ambidexterous - APRH100388C | 105 |
| Gas Block | Forward Control Designs Steel Gas Block | 57 |
| Total | 1644 |
I would like $1200 OBO (shipped) for this setup. It has approximately 500 rounds down the pipe.
the full length arca rail handguard by CMT is superb, adding weight and tripod/bipod ideal flexibility. I would consider selling without the Geissele Bolt Carrier, to reduce the price, if necessary. You would still get the headspaced JP Bolt, just need to provide your own carrier (tested with JP FMOS, worked well).
I also tested this on a variety of magazines once I figured out the gas system, and can confirm it works reliably with both grendel mags, and dedicated 6mm arc mags, and will feed from both ASC and duramags without issue.
A few edges on the hand guard have the black paint scratched off near the upper receiver side, I tried to photograph those closely so there's no surprises to the condition. The pic rail on the upper has silver sharpie from the scope mount, which will be removed before shipping. This also clears the superlative arms gasblock (others have asked this before).
I included a few shot groups with hornady black, and chrono data for both hornady black and hornady match.
Pics (scope and mount not for sale, sorry):
hornady black:
horandy match:
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