Seriously, all jokes aside, I've used RL,-17 a lot in smaller cases with great results. But I don't think it's quite the same as 4350. When it first came out it was described to me that you could pretty safely use 4350 data to begin working up a load, but things changed somewhat as you went along.
For one thing, I've heard that it is somewhat in the league with Superformance Powders in that It is not like most powders because it contains its inhibitors within the powder formula and not just dusted on the outside of the grains as in most powders. I was told this contributes to a slower pressure curve and it has less of a pressure peak. This is what I've been told. I'm no chemist and you can take all this with a grain of salt and do your own research. I called Alliant and spoke with a customer service rep and told him what I had been told. He wouldn't deny any of it but thanked me for the info.
However, upon the advice of a friend who had used it in his 6mm Remington with great results, I worked up a load with it for my .250 Savage. I got tremendous results with really great velocities with no visible signs of pressure. Also note that this was with 115 grain bullets, not 100s. However I did find that I was a bit over pressure when I went to reprime the cases and found that this load had loosened the primer pockets. At that powder charge it was expanding the case heads.
I destroyed those cases and loaded new ones dropping the charge a couple grains lower. Then worked it up again slowly (This took around six months because I was being very cautious and also it was a wet year and I couldn't always get to my range when it rained too much.). I got it up to 1 grain less than before with no signs of pressure and no problem with primer pocket expansion and called that good. I found I still got fantastic velocity and good accuracy with no signs of excessive pressure and the primer pockets didn't expand noticeably. That was good enough for me.
For safety sake I won't list my powder charge or velocity here in case my results are a fluke, because I have a 26" barrel and my chamber has a long throat. It's on a Howa 1500 action which I believe has a longer Magazine than a Remington short action so I have more room to seat bullets longer which gives me more powder capacity without excessive pressure. I'll just say it puts the already excellent little .250 Savage in a bit higher class even with the heavier bullets.
Those are my results with RL-17 in a .250 Savage and I had reasonably good results wth it in my .257 AI but I don't know how well it works in longer, higher capacity cases such as a .270 or .06. Proceed at your own risk, LOL!
Last edited by Filaman; 03/20/20.
