I am building a 280 and plan to shoot 139/140 and 150 grain bullets. It seems to me, by reading other posts, that many prefer RL 19,21, and 25. I have heard that this powder can be 'spikey' and temperature sensitive. Is this true? Where I practice and shoot it can be 60% to 100% and where I hunt it can be 30% to 100%. I plan on loading pretty close to max. Should I worry about the RLs or not? Thanks, capt david

I've used RL 19 and had good results but if you are worried about extremes in temp I would look to H 4831 SC.

I have had little luck w/ RL in my .280. For 140-150gr bullets, H4831sc is tough to beat, although IMR4831 is also good w/ 140gr bullets. For bullets heavier, IMR7828ssc is a great performer in my .280.

Fred is spot on. I have had not so great results with RL19 and 22 in my 280. H4831sc in 2 280s and an AI have really shot well. Close to or at max with H4831sc and a 140Accubond is series whitetail medicine