Originally Posted by mathman
I look at it like this: Having a larger capacity, the Swede loaded to modern pressure should be able to best the velocities obtained from a 260 Remington.

That's true, and that seems to be the case here.

Nominal case capacities
Code
.260 Rem            53
 6.5x55             57

So that gives the Swede about 7.5% capacity advantage over the 260 Rem. Using JB's 4-to-1 Rule (any increase in case capacity results about 1/4 that much extra velocity) would yield the 6.5x55 an additional 1.9% velocity over the .260 Rem (when loaded to the .260 Rem pressure levels).

Hodgdon lists 120g Speer SP w/ 43.0g IMR 4350 for 2,885 fps (@58,000 psi). That would suggest you could safely get to ~2,940 fps at the same pressure level in the Swede. Although it would take more powder in the Swede to get to that velocity level due to it's larger case capacity.

Looks like jwall is already in that ballpark with Denton's loads.

Last edited by Azar; 05/04/16. Reason: Fixed typo
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