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Old July 21st, 2021, 08:30 AM #3
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balttigger balttigger is offline
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Join Date: Oct 2008
Location: Middle River, MD
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balttigger balttigger is offline
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Join Date: Oct 2008
Location: Middle River, MD
Posts: 2,944
Just piddling around with the numbers using a .270/.308 as a base round shooting a 145gr Hornady ELD-X @ ~62,000psi. Using the same test length barrel as 6.5CM (28 inches), the 270/308 would punch that pill at approx 3,000 fps for ~2900 ft/lb energy. The 6.5CM using a 143gr ELD-X is 2,710fps @ 2,283 ft/lb (per wikipedia). I would expect an all brass cartridge formed to a Sig Fury chamber would be able to hold more powder and get 270/308 numbers or better easily.

A more reasonable hunting length barrel of 20" would put out ~2,875fps @ ~2,660 ft/lb on a bullet with a ballistic coeff of .536 (G1) giving an 850yd hunting range and supersonic out to 1350yds or just over 3/4 mile.

Not too shabby.
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