I finally got out for some range time today. Shot the FA556K on two rifles. LWRC 10.5" SRT gas piston upper/SBR, and a Colt 6920 14.5" w/perm attached flash hider mount.
Forgot the camera, so no pics. But here is what I learned today.
-Suppresson. The 10.5" still rings my ears. It's not really uncomfortable, but it's still loud. I wouldnt want to shoot this much without hearing protection.
14.5" was better, didnt ring my ears, but the crack is still pretty loud.
About on par with the other 5.56 rifle cans I've heard
-reliability. Both guns ran 100%. The LWRC did blow two primers (Black Hills MK262).
-Accuracy/POI shift. Both guns did group slightly better suppressed. The 14.5" did the best. I'm still looking for a load that the LWRC really likes. I've never been able to get better than 2.5-3" groupa at 50 yards, off the bench with this gun.
The 10.5" did exhibit some POI shift. It shot about 1.5" higher with the can on.
The 14.5" did not show any noticable POI shift between un-suppressed and suppressed.
-Gas blowback/fowling. The 10.5 LWRC did not seem to have any blowback at all. I ran a quick 30 rounds thru it, and my eyes didnt water.
The 14.5 DI did show some bowback, but not much. The only time I noticed it was about 20 rounds into a 30 round magazine, rapid fire. My eyes did start to water some.
I was wearing UVEX shooting/safety glasses for both. No unburnt powder in my teeth, or anything like that with either gun.
The piston gun is much cleaner inside, than the DI gun. Much, much cleaner.
No problems getting the can on, or off. While it was still warm, it was easy to remove.
Overall, I'm happy with it. I may look into an Ops can in .308 for my SR-25 now.