Originally Posted by The Guide
Does it look like RL-17 will work good in all of the cartridges based on the 308 casing? I have a 243 win, 2 in 7mm-08 rem, and a I just picked up a 308 win too. Sure would be nice if I could use all the same powder in all 4 guns. I am a new reloader (or soon to be reloader) and would enjoy having as few components to source as I can. I have a 338 AX coming from Kirby and might have it this fall so need to practice on how to "roll my own".
I have just started using RL-17 myself. I am using it in .308 with Berger 185g Classic Hunter Hybrids for F-Class and have had excellent results.
In regards to your question, my understanding is that RL-17 offers advantages with heavy bullets in any cartridge that does its best work with powders in the 4350 to 4831 burn rate range. That especially seems to be true in cartridges that show compressed charges of those powders with heavy bullets. I am basing this mostly on what I have read since RL-17 was introduced, rather than extensive experience.
Based on what I have read, I would say that 7-08 with 160g+ bullets would be a good application for RL-17. I'm not sure about .260. I don't think it would do anything special for you in .243 because that cartridge does its best work with slower powders.
I would like to try it in 30-06 with 215g Berger Hybrids, in 338-06AI with 225 to 250g bullets, and in 375 H&H with 300g and 350g bullets. In the 375, I am having such good results with H4350 and 300g bullets that I am having trouble finding a reason to try RL-17. I may feel differently when I step up to 350g bullets, or I might do it just to satisfy my curiosity.
In short, my thinking is that any cartridge that works well with H4350, but runs just a bit short of capacity before reaching max pressures is an excellent candidate for RL-17. I guess I will see if my thinking on that evolves with further testing.