Thread: Short fatties vs long slender ones...

I found the old Handloader Magazine that Grandpamac mentioned about the .300 WSM vs .300 H&H Holland. It's the February 2007, No 245 on pages 95, 96 and 97.
The 300 H&H and 300 WSM have virtually the same case capacity. Both chambers were given the same amount of throat.

Using the 180 grain Nosler Partition:
.300 WSM RL-19 at 67.0 grains gave 2,918 fps at 56,064 psi Velocity spread 13 fps.

.300 H&H Rl-19 at 67.0 grains gave 2,914 fps at 57,177 psi, Velocity spread 9 fps."

So the 'short and fat' 300WSM has no velocity difference over the 'long and slender' 300 H&H.

Another test:
"A series of tests were described in 'The American Rifleman' 1981. Three cases were tested, all of the same capacity, and all necked to take identical .22 caliber bullets.
1st case - conventional body taper and a long 14-degree shoulder.
2nd case - very long body taper and a 35-degree shoulder.
3rd case - little body taper and a concave radius shoulder.

Velocities and pressures were measured by both electronic-transducer and copper-crusher methods.
It was reported that the performance was almost identical, within the expected error. This very carefully controlled laboratory experiment found no difference in ballistic performance.

So this confirms that 'short fatties vs long and slender' case shape has no effect on velocity.