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Old 12-24-2017, 11:05 AM
Nyksta Nyksta is offline
 
Join Date: Dec 2014
Location: Calgary
Posts: 1,542
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Quote:
Originally Posted by marxman View Post
Somebody always says this. Without s.d. its misleading. Why would anyone ever shoot a higher s.d. bullet when a lower s.d. bullet would be faster. You didnt tell us the speed of the 308 x180gr. Compared to the similar 270x140
270 140 grain (sd=261) is more similar to 308 168 gr. (Sd=253)

Compare 270 cal 150 (sd=279) to 308 180 (sd=271) and that would be closer.

As caliber drops, you need a slightly higher sectional density to compensate for less overall mass.

I didnt look up the velocities or bc's of said bullets this time, but i already know that impact energies are extremely close at all ranges from muzzle to 500 meters and the drift is about 1% better for 270 So it pretty much comes down to whatever cartridge turns you on more
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