what causes uneven bc gap?

Are you measuring from the same spot every time?

Are removing the factor of endshake by either measuring with the cylinder held forward or held back?

An uneven cylinder face seems most likely.

WrongHanded said:

An uneven cylinder face seems most likely.

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I agree. That was what I thought when I read the OP.

I would call Ruger.

.011 is a big gap.

There is at least one custom shop that faces off the cylinder flat and square, along with the barrel breech for close and consistent gap.
Sometimes you have to have the factory work finished.

It would be really interesting to shoot some rounds over a chronograph and see if that larger b/c gap is causing any noticable reduction in velocity. 5 rounds per chamber should suffice (so long as you can keep track of which shots are from which chamber).

WrongHanded said:

It would be really interesting to shoot some rounds over a chronograph and see if that larger b/c gap is causing any noticable reduction in velocity. 5 rounds per chamber should suffice (so long as you can keep track of which shots are from which chamber).

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I want to say that it wasn't unheard-of in at least one shooting discipline to number the chambers and test them against each other and only single load the particular chamber that was most accurate once upon a time.

Don't know about Ruger but S&W's range for an acceptable gap is .004" to .010".

Obturation said:

.011 is a big gap.

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Par for the course these days with revolver manufacturers. You'd be lucky to get anything less than .006" gap with any current production revolver under $900.

Howdy

Closing the gate after the horse left.

Kuhnhausen says acceptable barrel/cylinder gap for Rugers is .004/.006 for revolvers set up for jacketed bullets, .008+ in revolvers set up for lubricated soft lead bullets.

He does not mention the amount of perpendicularity that is acceptable for the front face of the cylinder. You are saying .008 to .011. That is .003 from one extreme to the other. I would be surprised if Ruger routinely holds the cylinder face to much better than .002 for perpendicularity to the center pin.

It will be interesting to see what they say.

WrongHanded said:

It would be really interesting to shoot some rounds over a chronograph and see if that larger b/c gap is causing any noticable reduction in velocity. 5 rounds per chamber should suffice (so long as you can keep track of which shots are from which chamber).

Click to expand...

I really doubt if you would see much measurable difference in velocity with a variation of .003 of the size of the barrel/cylinder gap.

I think the Flattop .45/.45 is a good choice in a single action.
But were you shooting your Redhawk double action?

I would be very pleased with a .45 flat top. Glad they worked with you. I hope you like it.