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I didn't mean to start a discussion on actual barrel bending. I misspoke earlier, in my mind I was think barrel harmonics.
Anyway, personal story time. I have a 35 Whelen on a Mauser action with a 24" barrel that came with a "pepper pot" muzzle brake. Similar to the internet picture below.
![[Image: Bull_Barrel_Both_2__71415.1666292725.png?c=2]](https://cdn11.bigcommerce.com/s-dv1tqne/images/stencil/1280x1280/products/76865/90593/Bull_Barrel_Both_2__71415.1666292725.png?c=2)
Two inch vertical shift up at 50 yards when I took the muzzle brake off.
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Not sure what is going on with the Tikka altralite in 30-06( small threads for the thin barrel). Point of impact changes with a suppressor thats a fact but in the 7" configiuration the Bannish is a foot low and left @ 25 yards and can not be zeroed at 100 yards! In the 9" configiuration it is only low left a couple of inches just about what the Gemtec and TABC are. The 7" configuration works just fine on the Grendel, 300Blackout and 223s.
At any rate i run the Gemteck quick detatch between the Tikka 30-06 and Grendel AR and the Bannish dirrect thread in 7" between the Blackout and 223s. All 4 guns are sighted in with the respective suppressor on and not shot without the suppressor!
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This is a good read on barrel harmonics to help visualize what is happening when you add weight and or length to a barrel.
https://www.shootingsoftware.com/barrel.htm
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Klem Wrote:Mach,
What you say here is intriguing. What exactly do you mean?
Are you saying all the shots go in a tight group but in a particular direction outside the scopes adjustment travel?
Is the suppressor group size roughly the same as when the suppressor is off?
What is the muzzle thread on your Tikka-3?
It groups just fine and no baffle strike but the group is 1.5 feet low and a foot left at 25 yards! This only happens in 7 inch configuration on the 06. One other anomaly is that all other goups run a consistant 1 to 1.5 inches low left at 100 yards with the suppressor and it matters very little calibar or suppressor
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MachV Wrote:It groups just fine and no baffle strike but the group is 1.5 feet low and a foot left at 25 yards! This only happens in 7 inch configuration on the 06. One other anomaly is that all other goups run a consistant 1 to 1.5 inches low left at 100 yards with the suppressor and it matters very little calibar or suppressor
Mach,
Sounds like your 30-06 barrel's muzzle thread is not allowing the 7" suppressor to square with the bore. The interface between the 30-06 muzzle and the 7" is off somehow.
Sounds like the two suppressors (7" and 9") are perfectly fine. I say this because your 7" works fine on the Blackout, and the 9" works fine on everything. Blackout is the same bullet diameter as a 30-06, and if the problem was the suppressor then you'd have rounds going off axis in the Blackout also. You're only seeing wildly off groups in the 30-06. The more clearance in the smaller diameter calibres: 6.5 and 223 means any runout issues will be more forgiving. But, comparing the Blackout with the 30-06 suggests the problem is the 30-06 muzzle.
All suppressors change the MPI about 1-2" at 100, so that's normal. But 1.5ft at 25yds is clearly an off axis suppressor. Rounds don't have to strike the baffles to be deflected. Gas can escape more on one side than the other, throwing the bullets off axis. Suppressors only have about 0.5mm clearance between bullets and baffles so it doesn't take much runout to throw bullets off.
