COAL and OAL?

[alphabrace]

What is the difference between COAL and OAL?

[s&wchad]

Cartridge over-all length (C.O.A.L.) and over-all length (O.A.L.) mean the same... at least they do when you're talking about cartridges.

It's usually measured with a caliper from the tip of the bullet to the case head. S.A.A.M.I. specified cartridge O.A.L. is designed to insure that loaded cartridges fit in the magazine and the ogive on production bullets is safely clear of the rifling. You can usually adjust the bullet seating depth and find a sweet spot that yields better accuracy for a specific gun. Comparators that gauge off the ogive (like the seating die for a pointed bullet) give a more meaningful reading, because bullets vary within the same lot.

[moxie]

OAL and COAL like S&Wchad said are the same. OAL was the term of choice for many moons, but the COAL term crept into the lexicon for some unknown reason. The C is redundant and unnecessary, as we know it's the length of the cartridge we're talking about.