I was making some 510 Whisper cartridges this afternoon (Sako TRG) and when I looked up at some SOCOM cases that needed sizing..... well you get the idea. A 650 AP when inserted into a SOCOM case thats had a 50 cal expander run down it,swells the neck out to .535 whereas the base is .538. I'm guessing when you put a few thousand CUP's to it, the case walls will straighten out
Afterward I got to looking at Skinner's "Cartridges of the World" and found the "50 American Eagle" described as a 50 Action Express opened to accept 50BMG projectiles... blah ..blah.... achieves about 1000 fps!
Starline describes the SOCOM case as a 50AE based case lengthened to 1.575 and the 50 AE is 1.285 so we have .290 more case length ....to stuff full of powder?
I know headspacing off the case mouth isnt "ideal" but its not impossible and it will work without much brass flow at low pressure (subsonic).
No, its not a Whisper, but the brass is cheap and I dont have to spend hours on the lathe to come up with a hundred cases. I think I'll order a reamer t'morrow.
I might have to try this on a Savage..............
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