Slugs V pellets.

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Trouble with wind science is "it's not constant" the wind itself. If it were the calculations would always be true. But dirrection and speed is always on the move. Then if your mainly a pester like, although I shoot on the gench often, you have extreme vertical involved where hoizontal distance is rather short but vertical maybe almost twice that distance. So time in flight and wind effect is multiplied. I am also finding as I did flying the wind dirrection is much different as vertical changes. THOUGHT'S?
 
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Don’t know, since we don’t shoot at 500 FPS. I do know that if I had bumped the speed up to 1080 FPS the drift would have been worse not better... You can’t think of higher speed as making wind drift better. With subsonic pellets it doesn’t work that way. You have to look at what happens to the BC with specific MVs. In this specific case, the 25.4 JSB Kings exhibit the highest BC at about 850 to 925 FPS. So going from 888 to 1000, or higher, you are lowering the BC. And since wind drift is proportional to BC and NOT speed, the wind drift will increase.
Going from 888 to 1080 the drift at 100 yards in a 10mph cross wind increases drift from 10.3 to 11.6 MOA at 100 yards with the pellet listed above. Blows your mind doesn’t it?

You will think “the pellet is faster, and spends less time in the wind, so the wind just can’t affect it as much”. But the science says the pellets slows down faster at that higher speed, so it’s BC is less, and therefore the wind has a greater effect. Hard to believe? Yup. Hard to believe the sun doesn’t revolve around the earth too, but it doesn’t...
 
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One reason this subject resonated with me was I am considering a RTI prophet in .22 (over the .25) the reason being it's "High speed barrels" capability of shooting JSB 25g at 1000fps+ for better accuracy.

so, "better" only it there is no wind.

Please don't even dignify this with a response if it is WAY of the mark.

"my head hurts"😅 very good.
 
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No, it’s a good question. And therein lies the rub. .22 RD Monsters act like a pellet/slug hybrid, or a plug. So it’s BC curve is shifted to the right more like a slug than a regular diabolo pellet. So it’s up to 1000 FPS, even a little higher before the plug’s BC starts to decrease. In this case you get the benefit of the higher speed with none of the downside until you go much over 1000 FPS. I shot the RDMs at 995 in my Bleu Wolf no problem. I ended up settling on 975 because they were more accurate and the gun was more efficient there. So this “plug” is the exception to the rule, as there always seems to be... 
 
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I think one of the reasons why it is so hard to wrap one's head around this is that there is a bit of a curve that is involved. That is to say that, at pellet gun velocities what Centercut describes is 100% correct. Once the velocities get to a certain point though the wind drift goes down as the velocities go up. Let's use the example of the 22-250 that was described in an earlier post. I use a Hornady 53 gn bullet with a BC of 0.29. At a velocity of 3700 FPS the drift at 500 yards is 34.3 inches. If we slow the velocity down to 3300 fps the wind drift grows to 40.0 inches at 500 yards.

Let's take that same exact bullet and run it at pellet gun velocities using the values that Centercut used. At 985 FPS the drift is 57.8 inches at 500 yards. At 1085 FPS the drift grows to 64.6 inches at 500 yards.

All of these drift values were obtained with the online federal ballistics calculator.

Guys (like me) who started in powder burners and then took up airguns have a bias based on what we (I) experienced at significantly different velocities. When I started playing with sub-sonic loads in 300 blackout I found that wind drift is not as simple as one would think. 

ETA: wind velocity used in the calculations was 15 mph
 
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