Bizarre 300 Win Mag behavior

[Pappabear]

How bad is the vertical stringing? Maybe an ignition prob. Are you using magnum primers?

Not if they shoot great without the can. huh? I buffed the brake and barrel out. Cleaned end cap of can, hardly anything there but what the hell....

PB

[Bimmer]

Eyeballing the alignment through the chamber doesn't show anything alarming.

Did you do the pencil test?

... a sharpened #2 pencil is a perfect fit in a .308 barrel. Push one through the can, down the barrel, to check your clearance. (I learned this trick on TFL.)


Or maybe it's just a barrel harmonics problem? The combination of heavy bullets and the weight of the can is screwing things up?

[TomMcC]

Not if they shoot great without the can. huh? I buffed the brake and barrel out. Cleaned end cap of can, hardly anything there but what the hell....

PB

Then I misunderstood what markm meant by "stacking". Looking back I guess it means stacking one shot on the other, not vertical stringing.

[markm]

I think that they may be in the verge of instability. How do they shoot at extended range with the can off? Say 800-1200?

Good. I shot 3 rounds at 1300 yards. No fanning out or anything.

[Pappabear]

Yes, stacking holes inside one another. Not walking up the paper.

[lsllc]

So always good with no can...

Sometimes ok with can, sometimes not ok with the can.

How’s the bedding and action torque? Perhaps the weight of the can could also be causing some form of changes in barrel harmonics.

The key change seems to be suppressor related.


Sent from my iPhone using Tapatalk

[Pappabear]

Did you do the pencil test?

... a sharpened #2 pencil is a perfect fit in a .308 barrel. Push one through the can, down the barrel, to check your clearance. (I learned this trick on TFL.)


Or maybe it's just a barrel harmonics problem? The combination of heavy bullets and the weight of the can is screwing things up?

Yes, it dropped through like it (#2 Pencil) had eyes. And I checked the screws, they were tight.

PB

[Pappabear]

So always good with no can...

Sometimes ok with can, sometimes not ok with the can.

How’s the bedding and action torque? Perhaps the weight of the can could also be causing some form of changes in barrel harmonics.

The key change seems to be suppressor related.


Sent from my iPhone using Tapatalk

Yes yes and yes it could be harmonics, good idea. I thought the same.

PB

[eightmillimeter]

Find a way to get another 50 FPS on that load by upping the charge or switching powder. You’ve got more recoil force and a slower bullet with that heavy and the gun may have started moving a c-hair before the pill is out of the can. That’s my official guess.

[Pappabear]

Find a way to get another 50 FPS on that load by upping the charge or switching powder. You’ve got more recoil force and a slower bullet with that heavy and the gun may have started moving a c-hair before the pill is out of the can. That’s my official guess.

We loaded some hunting bullets at 75grains but went back to 74.5 H1K because it was so hot on the brass, we can take some of those loads.

PB