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44 40 wind drift

Posted: Tue May 22, 2018 9:53 am
by Porpoise
i was thinking about going supersonic with my 44 40 loads to 200 meters. i went on hornady ballistic calculater and couldnt find wind drift but the speed from 1350 to my 1050 speed drops more than twice as fast as below 1050 even though its only about 30 percent faster to start out. i am aware of transonic increased resistance my question is do you improve on wind drift with the faster load. it seems like you could actually lose. if i have to start at 1800 to get to 200 supersonic with my low bc bullet thats no good. to make a long story short is a 1350 fps load any better than a 1050 fps load over 200 meters. i know the 44 40 is a crappy round for cowboy highpower i use my 30 30 but i am shooting the 44 40 for fun

Re: 44 40 wind drift

Posted: Tue May 22, 2018 11:13 am
by thauglor
The faster you start, the faster the bullet will get to the target; lower wind drift is always a benefit from going faster. Going faster doesn't always mean more accuracy though.

I use the following calculator to for wind drift and bullet drop
http://www.jbmballistics.com/cgi-bin/jbmtraj-5.1.cgi

Re: 44 40 wind drift

Posted: Tue May 22, 2018 12:11 pm
by Porpoise
i checked that site it gives me better drop numbers but about 30 percent more wind drift with the faster load. 1350 vs 1050 i mean for speed

Re: 44 40 wind drift

Posted: Tue May 22, 2018 12:13 pm
by BrentD
Porpoise wrote: Tue May 22, 2018 12:11 pm i checked that site it gives me better drop numbers but about 30 percent more wind drift with the faster load. 1350 vs 1050 i mean for speed
That is surprising. I just ran through it with numbers for .22 LR, and it was always less winddrift for faster bullets.

Re: 44 40 wind drift

Posted: Tue May 22, 2018 12:33 pm
by Porpoise
i just tried it with 22 cal 40 gr. bc .15. i got 20.8 drop with 18.1 inch wind drift at 1250 fps. at subsonic 1050 i got 26.7 drop and 14.2 wind drift. according to the calculator the drop increases but the wind drift decreases. thats 10 mph crosswind

Re: 44 40 wind drift

Posted: Tue May 22, 2018 12:37 pm
by Porpoise
for the 1350 speed the wind drift is even more pronounced but i wanted to compare common 22 high vel and 22 standard

Re: 44 40 wind drift

Posted: Tue May 22, 2018 12:40 pm
by BrentD
Porpoise wrote: Tue May 22, 2018 12:33 pm i just tried it with 22 cal 40 gr. bc .15. i got 20.8 drop with 18.1 inch wind drift at 1250 fps. at subsonic 1050 i got 26.7 drop and 14.2 wind drift. according to the calculator the drop increases but the wind drift decreases. thats 10 mph crosswind
I was reading the wrong column. My mistake.

The increase in wind drift with velocity is the story I've always heard, although thauglor's explanation always made more sense. The issue, I believe, is related to how BC changes with velocity, though I don't fully understand the details. However, a bullet with a BC of .15 at 1050 fps will not have a BC of .15 at 1500 fps.