Quote:
Originally Posted by TomkinsSP
COL or OAL may be significant for feeding a semi or fitting cartridges into a cylinder. But it is irrelevant for loading the cartridge. The Useable Volume under the bullet is important, but different bullets of different shapes and different lead alloys and different jacket design/thickness and different plating thicknesses will have different Useable Volumes at the same bullet weights and OALs. The way to know for sure is to measure them.
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Yes, you can only use COL as a surrogate for residual case volume when the bullets are the same length and perhaps base profile.
Fortunately, a Speer 115gr GDHP @ factory spec is 0.560". That's a good enough match for Berrys (.556-.564) which was the OP's specific question, as well as Xtreme (0.553-0.557) and Precision Delta (.560-.564). According to Quickload, other brand name FMJ bullets are in that same ballpark too.
I suspect that's why Hodgdon can continue to list only the GDHP as the example of a copper surfaced bullet.
(I've never seen a 115gr LRN, but Hodgdon's 1.100" test COL has always made me curious. Anyone know the length of a typical LRN? Unless they are really short, that may help explain the lower powder charge range.)