HighDesertWolf. you may want to reconsider and use a 7mm Rem. Mag. with 160 gr. Sierra Pro Hunter. Your 338 UM will drift 3.2" at 200 and 7.6" at 300 in a 10 mph. breeze. The 7mm Rem. Mag. will drift 2.9" at 200 and 6.8" at 300 and you will have some useable meat after the shot.

There is not enough difference between the two regarding wind drift to make the difference!! And the Lost River Ballistics bullet is LOOONNNNGGGG, not like a typical bullet. There is an air gap in the middle. Its like a Barnes X with a bigger center, and then a larger copper tip put into there, with a gap between. The bullets have something like a .750 BC. Its pretty amazing stuff!!

Looks like we got another arm chair ballistics expert on our hands charlie.....
where did you get that data sniper??? from your exterior ballistics software?? software is not reality.......
before you go off telling me whats what........ My ears would be a little more open if you could tell me that wind drift data was from one of your shooting log books. I log all my handloads and most or there exterior ballistics if I am happy with a loads accuracy. I will tell you straight up with my experience with lost river J40 190 grain match bullets (BC is .774) and my sporterized Springfield 03-A3 ( glass bedded walnut stock, jarden trigger, shepherd 6-18x40 scope). I'll put my rifle up against any rifle of your choice in a 600 meter match you just name the time and place.

by the way the 338 cal 250 grain J36 has a BC of .661, your 7 mag with a 160 grain bullet..... (sierra doesnt make a 160 grain pro hunter) probably the best BC for a 160 grain .284 cal bullet would be a nosler partition even then its BC is only .475, a 7 mag pushes a 160 grain bullet around the same velocity as a 338 RUM with a 250 grain bullet so from experince with the J36 bullets I would flip flop your numbers around that would then make that 338 load to have better wind resistance then that 7 mag load. but either way those numbers you posted are very marginal and are not nearly enough to say one is better then the other for windy conditions.

I hunt in Wyoming all the time and I use a 7mm RUM with a 160gr Nosler Partition with 94 gr. of Retumbo powder. It's fast, flat and generates it's own wind! j/k

Growing up in Wyoming you learn how to shoot in it. I must admit the wind really whistles in Wyo., but it usually is very constant on direction which is nice. Overall though, most of us don't think about it much unless we are shooting long distances.

Right on bud, those RUM's practically do make their own wind LOL they sure do send a bullet screaming, only thing better is Lazzeroni's firebird or warbird cartridges the firebird pushes a .284 cal 160 grain bullet at 3,550 fps and the warbird pushes a .308 cal 150 grain bullet at 3,775 fps talk about making some wind