Running a A5 system on a 14.5" Adams Upper. Standard weight BCG.
I'm encountering multiple FTFs. I get a clean 4 o'clock ejection, but 90% of the time the bolt is going home with nothing in the chamber.
Here are the different things I've tried.
- Checked piston rod and cup to ensure it was straight and true. Examined piston spring, buffer spring, and BCG for any binding. All appears to be in order.
- Gas system full on > Gas system on suppressed (no can)
*Suppressed lead to FTEs, w/the bolt face locked back 1/4" from the ejector port which I would consider normal function unless I had a can on the muzzle.
- Multiple 30 Rd PMag > 20 Rd Thermold
*Never get more than one shot from a PMag. 2-3 sporadically from the Thermies. Did not have any STANAG mags on hand to test.
- 10 oz Heavy Buffer > 4.6 oz H1 Light Buffer
*No change
- XM193 > XM855 > Fusion 62 gr
*No change
Edit:
- Checked to ensure Rifle, and not a Carbine length spring was used.
Unlike AA's aftermarket kits, their fully built upper comes with a staked gas block so I wasn't able to examine if the ports were possibly misaligned, but that's extremely rare on a staked block that was factory tested (I presume) before being shipped.
I'm left thinking that perhaps the A5 is a contributing element to the problem since it's the only other 'non standard' operational component on the rifle.
I left the rifle with a well known gunsmith in another state to see if he can possibly work out what's going on. Of course being good often means being in demand, and being in demand is commensurate with a 4-5 week wait time so I won't be seeing that rig until Decemeber (maybe).
Still, for my own education and edification I'll like to see what others think.