the PCC division of USPSA has given a new life to a lot of us old guys... shoulder fired, dot scope, high capacity...and you get to shoot pistol distance targets with it...
my first venture was with a MechTech carbine for my small frame Glocks... I had some tolerance stacking problems with the G34, but the G17 worked fine...the design, however, used an extension recoil spring, and there was not an easy way to tune the action for reduced power loads... the division only requires a 125 power factor
my choice was to stay with Glock due to the excellent 32 round magazine...I wanted to stay with the AR platform as that was what I'm the most familiar with...my lower is a New Frontier Armory billet unit, and my back up is a Palmetto State Armory that is made by NFA and varies only in roll mark... my original upper was an Aero Precision and barrel from MAS Defense, NFA modular bolt, and round handguard...a friend purchased both upper and lower from PSA, and I like the feel of the handguard, so ordered a PSA upper, which is what I have settled on....the original PSA barrel needed to be chamber reamed to accept the longer 1.140 bullets, so after reaming it replaced it with the original MAS barrel that had a deeper chamber... topped with a Miculek style 9mm brake... using the PSA bolt... I don't have a need for a side charger or last round bolt hold open ... the PSA bolt uses a pistol style extractor, while the NFA uses an AR style claw extractor... I had an incident when the roll pin holding the extractor in the NFA bolt came out and allowed the extractor to come out... luckily I found the extractor... replaced the roll pin with one that I spread a little with a sharp wood chisel to increase tension
I knew I was going to play with springs and buffer weight, and use an A1 full stock for my 5.56 competition carbine, so that was the choice for the AR9 also...I built several weight rifle length buffers , some with lead shot, full poured lead, a couple of different diameter brass slugs... once I settled on a load, currently a 135grain Bayou polymer coated with 3.6 grains of Win Super Field at 1.140" OAL, I started playing with different weight buffers to try to reduce dot movement...I tried heavy and light, and settled on a factory 5.2oz rifle buffer... when I shot groups, however and compared it to the Enidine hydraulic buffer from my 5.56, I was surprised to see that although the scope movement appeared the same, the double tap groups at 18m was considerably smaller with the hydraulic...the hydraulic is in the gun
for trigger I have Rock River NM units in my 5.56 guns, so stole one for the PCC.... tried several scopes... Trijicon 1.5x ACOG, ACOG reflex, Vortex Spitfire and Vortex SPARCII... I have a pretty bad astigmatism, and the SPARC shows a round dot with the distance prescription in my bifocals...a Taylor Freelance +9 extension, and TACCOM coupler that connects a Glock 32 to a 17...a several round reduced loaded G17 mag is used for reloads...
PCC is a fun new division, unfortunately the go fast young guys are finding out how much fun it is... the short piston SIG MPX and JP AR are the most common high end guns in local use... most using CMore scopes