Group difference suppressed/un-suppressed

[usmc0352]

I have had great success with my PSA 20" grendel with my 7.62 AAC can on it and my 130 gr. TGK and TAC. Sub half MOA. I loaded some up using Match Rifle, shot them with A2 flash hider and no adjustment to gas. HORRIBLE groups! I couldn't find the right sized wrench to adjust. Any clues as to what size it is? POI shift was about 6" low and 2" left which is no problem. I'm making this my backup gun for Wy. Mule deer and want to save the 1.5lbs of weight. Do you think it was the gas? The harmonics/Gas? Very surprised this bullet shot shot so poorly. Rest was ROCK solid. I shot some 123 AMAX through it to confirm it wasn't just a bad load combo. Same results.unsuppressed unadjusted gas groups 130gr TGK - Copy.jpgsierra 130 gr TGK 27.0 TAC - Copy (2).jpg

[myrifle]

So you took a diffrent powder and used it with a load you already worked up and got bad groups?

Am I understanding that correctly?

[usmc0352]

Yes, a known stellar performing bullet but with a different powder and unsuppressed. Too many variables. Going to back up, shoot with the known well performing load again suppressed to verify there isn't a new issue with scope/mount etc.

I'm going on a Western hunt and would like to shed the weight of the can. Earplugs=less than an ounce, suppressor= 1.5lb.

[Double Naught Spy]

Yes, a known stellar performing bullet but with a different powder and unsuppressed. Too many variables. Going to back up, shoot with the known well performing load again suppressed to verify there isn't a new issue with scope/mount etc.

I'm going on a Western hunt and would like to shed the weight of the can. Earplugs=less than an ounce, suppressor= 1.5lb.

If you switched out your left front tire and now have a wobble in your steering, do you then go back and check the shocks to make sure they are correct? You can, but that would seem to be what you would check AFTER you determined if the new tire was at fault or not. Or, in your case, have you also messed with the scope/mount etc. as well changing the suppressor and powder?

Any time you add a suppressor to a rifle/load/bullet combo or remove a suppressor from a suppressor/rifle/bullet/load combo where everything was good before the alteration, you may get a change in group sizes. You may get a POI change.

Bottom line, you may have to work up a new load to get the same results with the suppressor off as you had with the suppressor on the rifle.

[usmc0352]

Some groups from today. With results like this it is worth it to just carry the extra weight of the can in my opinion. Only 3 shot groups but all are pretty decent! If it ain't broke.... I have lost 20lbs so I think I can afford 1.5 lbs of added rifle weight LOL
130 gr Sierra TGK 27.0 gr TAC 522 yards 12.5 MOA up - Copy.jpg123 gr SST 28.0 gr AR Comp 522 yards - Copy.jpg123 gr SST 28.0 gr TAC 522 yards jpg - Copy.jpg

[204 AR]

Those are great groups at that range imo! I'm betting the flash hider is your culprit, I'd try it with a bare muzzle if that's what you want. But honestly I'd hunt with the can on anyway.

[usmc0352]

Adjusted gas to cycle with or without suppressor and re sighted. Groups are good with or without suppressor. A 6" high change in POI without but good groups with several loads.