Newbie - How tight is tight?

[ILpaul]

I recently purchased a surplus CZ 83 .32 ACP (?esk? zbrojovka) from a forum member. The bore is immaculate, a lot of bluing wear and the plastic grips show more than occasional use. It must have bee fired!!!

I "slugged" the barrel today. I took over a dozen readings (they didn't make sense to me) with a Lyman digital caliper. I came up consistently with 0.3065" - 0.307".

Has anyone else done this operation? Did I mess up? How tight is tight?

Any input would be appreciated.

[eastman]

What are you expecting the result to be? 7.65 Browning uses a 0.309" bullet diameter.

Calling it a ".32" is an exaggeration that goes back to the old black powder rimfire days with the heeled bullets at the same diameter as the case.

[ILpaul]

My first .32 auto. My only other pistol is a S&W Model 19. I wasn't really sure what to expect. Hence the question. Commercial .32 ACP are 0.311" - 0.312".

Consensus suggests the optimal sizing for cast bullets is 0.001" over actual bore, with 0.002" over maximum.
For my pistol, that would put the bullet at 0.308" - 0.309" diameter. I just looked weird when compared to commercial bullets.

Thanks for the sanity check.

[eastman]

Cartridges of the World, 13th Edition lists the bullet diameter as 0.309". The revolver ".32"s are 0.312-0.313".