Quote:
Originally Posted by Dtmoss14
When does it start to falter?
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Depends almost entirely on the bullet chosen and not the rifle type (semi vs bolt etc, a good quality barrel in either is assumed). Ballistic coefficient must be high for longer range, but long bullets have to be spun faster in rifling so the barrel effects whether you can use this approach.
75 grain Hornady ELD Match bullets at 2650 FPS out of 1:8 rifling 20” barrel in an AR15 can stay supersonic out to 800 yards, remain transonic (maybe stable, maybe not) out to 1000 yards. Stability directly relates to accuracy. Once unstable, it is inaccurate.
90 gr ELD bullets may stay supersonic passed 1000 yards. These require at least 1:7 rifling so I haven’t used them.
Andrew - Lancaster, CA
NRA Life Member, Calguns.net contributor, CGF / SAF / CRPA / FPC / USCCA member