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M1NM
07-21-2012, 6:14 PM
Is there a formula to convert the fps out of a 24" barrel into the likely fps one could expect from a 20" barrel?
Want to make up some 223 match type ammo and noticed that Hornady 75 grain is going 2790 fps out of a 24" barrel. I've got a 20" barrel and wondered what I should aim for in fps.:confused:

StratORcaster
07-21-2012, 6:17 PM
I read that you can expect about 50 less fps per inch, so ~ 200 less?

J-cat
07-21-2012, 6:27 PM
I vote 50FPS per inch.