The Firing Line Forums - View Single Post - What other calibers share/use the same basic cartridge case?

Bart B. · January 1, 2013, 03:33 PM

Mike Irwin, the .270 Winchester (or 6.9x64mm) was developed by Winchester Repeating Arms Company in 1923 and unveiled in 1925 as a chambering for their bolt-action Model 54. 1923's twenty years later than 1903, so I doubt that old military cartridge was used as the basis for the .270.

Many cartridges "reformed" from parent ones will have a different case length than their parent case does. .243 and .270 Win are just a couple. Especially if the parent case is just sized down in the neck, it'll often be a few thousandths longer.

January 1, 2013, 03:33 PM	#25
Bart B. Senior Member Join Date: February 15, 2009 Posts: 8,927	Mike Irwin, the .270 Winchester (or 6.9x64mm) was developed by Winchester Repeating Arms Company in 1923 and unveiled in 1925 as a chambering for their bolt-action Model 54. 1923's twenty years later than 1903, so I doubt that old military cartridge was used as the basis for the .270. Many cartridges "reformed" from parent ones will have a different case length than their parent case does. .243 and .270 Win are just a couple. Especially if the parent case is just sized down in the neck, it'll often be a few thousandths longer.