I haven't seen the claim that AR Comp is more temp-resistant than RL-15. Where'd you find that? On the Alliant website they just claim both are consistent across a wide range of temperatures.

RL-15 is pretty good--or has been for the last 10-12 years, since it was reformulated for military use. But in my own tests it still isn't as temp-resistant as the Hodgdon Extremes. I haven't had a chance to test AR-Comp in cold weather yet, but it has shot real well in more than one .223. Can't remember trying it in any other case yet.

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