MAT9 Other Build · Training · 124 gr
In her maiden voyage, I couldn't get the gun to run. It refused to feed FMJ, my standard 124 gr S&B. Here is my summary.
Finally got my MAT9 (not from midway). I tried to cancel this order to move on to a dissent but my cancellation request was returned with a tracking number...since I have it now, I decided to build it out.
The Build: https://builderarmory.com/builds/mat9-otherbuild
Lower: Aero EPC-9, Fortis Torque
Stock/Brace Setup: A3 Tactical Brace, Arm, Riser, Strike 1913 adapter, Mod1 C
Internals & Controls: Rise PCC trigger, Strike safety, Strike takedown pins, Matador hydraulic buffer
Front End & Muzzle: Kaw Valley Blast Shield on a Plan B mount, vertical grip
Optics & Sights: Holosun 510C, Magpul offset iron sights, plus an Amazon laser because $30
Since assembling it, I’ve been obsessively hand-charging, cleaning, and lubing it to wear in the mating surfaces and build a smooth wear pattern.
Here’s what I’ve run into so far:
Failures to Feed (FTF): I can’t get this gun to run, whether racking it manually or live firing. It won't feed more than one round consecutively. I tried about 30 times, but getting it to reliably chamber 124gr Sellier & Bellot FMJ was completely impossible.
Hydraulic Buffer Issues: The buffers installed fine, but after a short range session, they’re fully retracted and stuck tight in the bolt carrier. Twisting frees them temporarily, but they’re useless if they collapse and freeze up every time. Getting them out completely is going to be a pain.
Mid-Stroke Friction: There’s a distinct drag halfway through the charge stroke. You can feel it with the upper off, but it’s way worse once mounted to the lower. That parasitic drag is almost certainly what’s killing the energy and causing the FTFs.
On top of that, the recoil impulse is unimpressive. Maybe I’m spoiled because I’ve built half a dozen AR9s this year all using some form of KynSHOT hydraulic systems, but I was expecting something better than those or a lot closer to an MP5 feel.
I only managed to get 9 total rounds through it today—and only 2 back-to-back. I went in with low expectations but was hoping I’d be one of the lucky ones who got a solid unit.