Let me preface this entire post with this... My AR shooting has been limited to Army quals almost 20 years ago (expert for what that's worth
) and short range blasting more recently. I'm new to shooting for groups outside of a 25m zero so go easy. Honestly , this was the first time I've shot for groups at 100 yards. I know nothing that follows is impressive. In fact, I'm pretty embarrassed with it. Especially embarrassed to post this in the precision rifle forum. I'm ready to start learning though
.
I just had a question.
How much zero shift/groups opening up should one expect while shooting suppressed at a fairly rapid rate?
My Aero 18 inch fluted SPR barrel shot well enough to satisfy Ballistic Advantages 3 round (yeah yeah
) sub MOA mag fed guarantee...at first. 5 round group was a bit larger. That was in spite of using American Eagle M193 with rusty me on the an ALG ACT single stage trigger. I had only put 10 rounds through it to function check it previously, then cleaned it.
Rifle in question. Budget barrel (Aero fluted SPR), ammo (AE M193), scope (PA GLx 2.5-10x44), single stage trigger (ALG ACT), and out of practice shooter behind it...lol.
Zeroing at 100 yards with American Eagle M193 cause that's what I have on hand. Want to try some match stuff soon.
Anyway, after about 100 rounds though it without letting it cool, the grouping had opened up and shifted quite a bit. There was considerable mirage coming off the barrel and suppressor. I was pretty much just loading mags and letting it rip.
Is this kind of group shift and growth pretty normal with a hot suppressed gun and bulk ammo or was I just getting way sloppy?
Banging a steel silhouette at 300 was still stupid easy the whole session though. Was double tapping it for fun getting the 2nd round off before I even heard the first hit without even having to try because I was getting bored.
All in all, it was a fun day. Just not great to end with what seemed like a shifted zero and much larger groups. Stayed minute of torso silhouette the whole time though at least