45 Auto Rim case cannelures

Here are a couple of 45 Auto Rims, one with two cannelures and the other with only one. Any significant reason for this?
45 aoto rim




Did you weigh these two cartridges to see if they are a different bullet weight or not?

John M.


I thought the same thing, The one with the single cannelure weighs 327.9 grains (21.249g) and the double cannelure weighs 324.7grains (21.023g). Pretty close.


Rimfire - I agree. That difference in overall cartridge weight, which would include any variables in the weight of bullet, case, powder and primer, to me indicates they are within spec to be called “the same.”

Wish I had an answer for you on the double cannelure. I only collect this cartridge if it has a .45 ACP/.45 Auto headstamp - giving me a “huge” collection of 2 specimens.

John Moss

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