Pictured above is a recent build using an upper purchased from Palmetto State Armory, who frequently offers insane deals on high quality upper receivers. Their private labelled house brand uppers include button rifled and cold hammer forged barrels, milspec uppers, and optional mil spec M16 bolt groups. The prices are extremely aggressive and their daily deals are always difficult to resist. After I disassembled the upper, I sent off the barrel to ar15barrels.com, who cut the barrel down to 14.7-inches and pinned/welded an A2 flash hider to make the minimum 16-inch non-NFA length. Note that I sent the barrel with the barrel nut I intended to use, as once the muzzle device is pinned and welded on, the gas block and barrel nut cannot be installed after the fact. Randall at ar15barrels.com turned the barrel around in days and within about a week I had my barrel back. He offers barrel contouring, cutting, gas port adjusting, and other machining services at very reasonable prices.
The bolt used in the above build was coated with NP3 by Robar Guns. As seen in my previous post, NP3 offers abrasion resistance, built in lubricity, and excellent corrosion resistance that is far and above the standard phosphate finish. To top it off, I finished the build with the excellent CMR rail from Centurion Arms, which offers light weight, and an extremely ergonomic and narrow diameter rail. I have several builds with this rail and I have to say it’s my favorite rail system so far. Other accessories include TangoDown’s vertical fore grip and BattleGrip, SureFire X300, Aimpoint PRO in a LaRue mount, Troy Industries flip up sights, and Viking Tactics sling.
Nice looking build, Tim. How did you attach that foregrip to the CMR rail?
I used a preproduction test shot of an accessory rail from Centurion Arms. You can also use a section of accessory rail for the OBR from LaRue Tactical.
Tim,
Did you have the opportunity to measure the gas port size on you PSA barrel? I have seen two trouble PSA barrels that were in the .093 area that were completely overgassed and would not run reliably regardless of the band-aid fixes that were tried. Curious if they have gotten their stuff together with their gas port sizing.
Nope. Did not bother. However I did run a few mags through the upper with no apparent issues with over gassing. Will keep an eye on it.
Tim,
What are your thoughts on the optimum fore/aft mounting location of a 1x optic?
For Comp M, I like it where you see it as it gives me better ability to index optic. For smaller T-1, I mount further back to gain field of view.
Rookie question, so I apologize in advance, but: why did you mount your front sight so far back? How are you activating the X300?
Thanks for introducing me to my new favorite retail site ever! 😀
Roll the support hand thumb up over the top of the forend and push the switch with your thumb. The sight is moved to allow room for the hand.
Is that a Redi-Mag attached to the lower receiver?
Yes, the Blue Force Gear Redi Mod, a skeletonized variant.
Are you using any kind of Bolt assist with the Redi-Mod?
No bolt release attachment used on Redi Mod.
Tim, what is youre experience of PSA’s lowers as I ordered one with the insane pricing you mention? After reading your experience with there uppers and I have turned a few friends toward the PSA uppers and the really like them. All my lowers are Colt and my uppers are Colt, BMC. Thanks for any assistance! bill