B/C gap measuring?
Posted: Thu Jan 24, 2013 12:19 pm
Looking around online, I get fifty different ways to check the barrel/cylinder gap on a revolver. With the cylinder static, pushed forward, pushed back. With and without cartridges in the chambers. Etc., etc.. I think some people only do it during a certain moon phase.....
I've always understood that with an empty cylinder pushed forward, that was the B/C gap. Pushed back was headspace, and the difference was end shake, or cylinder play. Or maybe I've read so much, I'm confusing them now?
My four revolvers are such:
Bearcat one, .003 forward, .005 back, endshake of .002.
Bearcat two, .005 forward, .007 back, endshake .002.
LCR-357, .004 forward, .008 back, .004 endshake.
LCR-22, .003 forward, .008 back, endshake .005.
I had a Single-Six that measured .003 and .007 after Ruger re-barreled it to fix a .012 B/C gap.
And with countersunk rim chambers like the Bearcat, I don't think the measurement is right with the cylinder pulled back, since the cylinder has a raised rim on the back that contacts the recoil shield?
I've always understood that with an empty cylinder pushed forward, that was the B/C gap. Pushed back was headspace, and the difference was end shake, or cylinder play. Or maybe I've read so much, I'm confusing them now?
My four revolvers are such:
Bearcat one, .003 forward, .005 back, endshake of .002.
Bearcat two, .005 forward, .007 back, endshake .002.
LCR-357, .004 forward, .008 back, .004 endshake.
LCR-22, .003 forward, .008 back, endshake .005.
I had a Single-Six that measured .003 and .007 after Ruger re-barreled it to fix a .012 B/C gap.
And with countersunk rim chambers like the Bearcat, I don't think the measurement is right with the cylinder pulled back, since the cylinder has a raised rim on the back that contacts the recoil shield?