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**Bud Helms** · April 13, 2000, 08:01 PM

WESHOOT2,

I've read the neck tension statement before. I need to understand what it means. Do you think the brass too "springy" for a taper crimp to establish neck tension?

Also, I need to understand something else. Why do you say that an auto cartridge's headspace is "based" on extractor tension holding the cartridge against the breech face. Headspace is a dimension, staying with auto pistols, measured from the breech face to the case mouth "step" in the barrel, with the breech in battery. Isn't it?

I mean if your extractor broke, you could still safely fire a round in a properly headspaced chamber, couldn't you? You wouldn't be able to extract a case, but headspace would still be within specs.

What has the extractor got to do with headspace?

Hypothetical question using a .45 ACP: If your case rim is .049, the extractor hook contact face is .056 off the breech face, the case is .898 long (head-to-mouth), and the in-battery chamber length is .902, then even if the case is fully forward in the chamber, the extractor won't be back against the rim.

April 13, 2000, 08:01 PM	#4
Bud Helms Senior Member Join Date: December 31, 1999 Location: Middle Georgia, USA Posts: 13,198	WESHOOT2, I've read the neck tension statement before. I need to understand what it means. Do you think the brass too "springy" for a taper crimp to establish neck tension? Also, I need to understand something else. Why do you say that an auto cartridge's headspace is "based" on extractor tension holding the cartridge against the breech face. Headspace is a dimension, staying with auto pistols, measured from the breech face to the case mouth "step" in the barrel, with the breech in battery. Isn't it? I mean if your extractor broke, you could still safely fire a round in a properly headspaced chamber, couldn't you? You wouldn't be able to extract a case, but headspace would still be within specs. What has the extractor got to do with headspace? Hypothetical question using a .45 ACP: If your case rim is .049, the extractor hook contact face is .056 off the breech face, the case is .898 long (head-to-mouth), and the in-battery chamber length is .902, then even if the case is fully forward in the chamber, the extractor won't be back against the rim.