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Otto-

Tell me about those assymetrical crowns.
Also note what the grouping was like with the gun that you worked on, what you did with the crowns, and how that effected how the gun printed a target.

The crowns on the Tolley are 'deeper' where the barrels meet, clearly showing up as evidence of the angle at which the barrels are soldered together. The 'faces' of the crowns are perpindicular to the bore axis of each barrel though.
Do you mean to say that you intentionally brought the crowns off perpindicular to the bore axis to achieve your results, or are you referring to depth when you describe your crowns as assymetrical?
Were the groups of your rifle printing as one barrel over the other, then fixed with tuning via muzzle crown depth?

For whatever it's worth, the rilfe muzzles on the NitroExpress banner at the top of the page also show recessed crowns. I think that gun's a Chapuis, I also think those are factory crowns. I know the resolution of the photo is crap and the lighting might be a little funny there, but from here the left barrel looks a schooch deeper than the right.
Go figure.

Thinking about it, I can imagine how slightly less barrel time could effectively lower a rifle's group on paper. The next thought is that if that were achieved with a deeply recessed crown, the wall of the counterbore made during the crowning effort could possibly kick the bullet's tail and screw the accuracy, necessitating a larger diameter counterbore as depth was increased so as to allow the barrel to continue upwards in recoil as the bullet flew straight on clear of the recessed muzzle crown.
There's a bit of movement here to consider.
Hm.

--Tinker

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--Self-Appointed Colonel, DRSS--

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