I've had zero issues with my Hellion cycling any ammo I've tried to date. My rifle is a tack driver with just using a non magnified Burris RT-1 I can ring steel silhouette targets at 200yds all day. My rifle is so accurate I feel like a cheat code has been enabled when using it.
Suppress it and it will feel like a nail gun sound and recoil-wise, it's spectacular!
I just need to swap the muzzle device and I'm good. I've got a few QD muzzle devices ready to go.
There is one from SIG that looks almost like the original Helion one, of course compatible with SIG cans only, that's the PITA about suppressors
Yes, gas block is on N. I had trouble cycling crappy ammo, Wolf .223REM....but it runs Wolf 5.56, Norma 5.56, Winchester 5.56, IMI 5.56...it surprised me since my budget AR runs ANYTHING I feed it. The Wolf .223 55gr failed to pick up a new round from the magazine after ejection. No big deal, I just use my AR for the cheap stuff. I need to do some research on zeroing rifles with a 4" height over bore though...I mounted an old RDS after removing the optic riser and it seems to coincide well with the iron sights for co-witness. I don't like my LPVO on the Hellion...way too high with a scope mount added to the height of the pic rail. Just look at Pro Digy's pic above....that looks at least 4" height over bore for the optic. I'll just need practice going from 25 yards out to 300 to get new/different hold points than I'm used to. I'm not a good enough shooter to call it a tack driver with that trigger though...