Suppressor(s): Existing atmosphere can change accuracy in a rifle?

[islandermyk]

So I took out the GAP and the new SDN6 can.




Did a 5 shot group cold bore without the can. It was fine and dandy. (Top left)
Okay.. now with the SDN6 on. (Top right) First shot dang near dead on. Second shot was right below it. Third one another inch below it. I was shooting pretty fast strings, but when I saw where that third one hit I pretty much freaked out and stopped for a minute or two. So I then shot the fourth one and got it dead nuts again (right beside the first shot) and the fifth one is on the left of the second shot.

Seeing that first group shot with the can on made me wonder....
Note the middle target. That one was with the can, but this time with a different shooting strategy.
After every shot in this 5 shot group I left the bolt open for little more than 3 seconds ejecting the spent cartridge.

So do you think the existing atmosphere from residual pressure in the can after a shot can cause a spread in groups?

By the way, I love this SDN6... been smacking steel at 1000 yards and everything inside that. It really shines from 800 and inside of that... and the rounds were hand loaded 175 gr SMKHPBT 43.7 gr Varget

[brutal]

Did you get the golfball?

[ray1970]

I don't think you could have any "residual pressure" in the suppressor.

Where is Hoser? He might have some knowledge on the subject.

[islandermyk]

Did you get the golfball?

yeas I did... and I brought that home with me

Got it dead smack center.

[islandermyk]

I don't think you could have any "residual pressure" in the suppressor.

Where is Hoser? He might have some knowledge on the subject.

I wonder cause when I was shooting faster strings smoke was coming out of the action... it got me thinking too that since the SDN6 is shorter... I don't know... It's driving me crazy trying to make sense of all this

[smchop]

Just an idea, but your spread was vertical. Since you were shooting faster, could it have been breathing? I don't have any kind of shift like that with my can ( different can but ? ) Thats the same load I run in my .308 43.7gr of Varget! Works great.

[brutal]

I wonder cause when I was shooting faster strings smoke was coming out of the action... it got me thinking too that since the SDN6 is shorter... I don't know... It's driving me crazy trying to make sense of all this

Lend me your can and I will figure it out for you.

[islandermyk]

Just an idea, but your spread was vertical. Since you were shooting faster, could it have been breathing? I don't have any kind of shift like that with my can ( different can but ? ) Thats the same load I run in my .308 43.7gr of Varget! Works great.

You could be right.. I wasn't watching my breathing on that one.

I was shooting prone....

It was that one time I pulled the bolt back and watched the case eject that caught my attention. The case almost acted like a plunger sucking the left over smoke out of the barrel this question...
Who knows.. it's my first can.. I'm pretty sure I'll have more weird questions coming along the more I shoot with them

[brutal]

You may need to swab it.

[C Ward]

Haven't seen a shift like that in either of my TBAC cans . My first guess would be a lack of preload on the bipod since it went away when you started concentrating again . That being said AAC has had a lot of issues with their QD mounts and if your can uses one that can cause issues also .