Slugged some 9mm bores...
Two RIA 1911's', a commercial Yugo Tokarev, and a CZ75B SA. The RIA's were .355, the Tokarev was a shade under at .3547, and the CZ was .356.
I also did a 'plunk' test with some dummy cartridges that were .357 diameter 125-grain bullets of 9mm ball profile, that I got from Widener's. They were seated into PMC brass at an overall of 1.159. The RIA's and the Tokarev took the cartridges fine, and the CZ also took them but with zero clearance (they didn't fall back out of the chamber, but pulled out easily with fingernails).
The CZ also has a short ball seat, and I have found that if a bullet has any significant amount of the cylindrical portion projecting from the case, the bullet will meet the lands before the cartridge is fully chambered. I've never had any problems with any factory ball ammo, or with handloads using standard-profile 9mm bullets. Handloads that were loaded with the cast 'smallball' 124-grainers, which have a long cylindrical portion, that worked well in my P1's and P38, would stop the slide on the CZ before it reached full battery.
Anyway, info for anybody who can use it [:)].
I also did a 'plunk' test with some dummy cartridges that were .357 diameter 125-grain bullets of 9mm ball profile, that I got from Widener's. They were seated into PMC brass at an overall of 1.159. The RIA's and the Tokarev took the cartridges fine, and the CZ also took them but with zero clearance (they didn't fall back out of the chamber, but pulled out easily with fingernails).
The CZ also has a short ball seat, and I have found that if a bullet has any significant amount of the cylindrical portion projecting from the case, the bullet will meet the lands before the cartridge is fully chambered. I've never had any problems with any factory ball ammo, or with handloads using standard-profile 9mm bullets. Handloads that were loaded with the cast 'smallball' 124-grainers, which have a long cylindrical portion, that worked well in my P1's and P38, would stop the slide on the CZ before it reached full battery.
Anyway, info for anybody who can use it [:)].
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Glad your groove diameters are so close to nominal.
What I never understood is why my two CZ-75s have perfectly normal throats when there are so many complaints about short throats. Did CZ change their bore specs when they went to the CZ-75Bs?
Personally, I generally load so the bullet just touches the lede/rifling/lands to eliminate head space which seems to improve accuracy.0
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