I want to reload some 180 grain nosler ballistic tips and some 220 grain Sierras
for the 8mm Rem Mag. I have a can of Reloader 25 and it's screaming to be used up.
Where do I start for the 180 grainer with R-25?
Where do I start for the 220 grainer with R-25?
Thank you!

Matt Rl25 is a little slower than RL22. There isn't a lot of data out for RL25 in any calibre let alone the 8mm Rem. I don't think it will be the best powder for the 180 gr Nosler(too slow). I would suggest you consider trying IMR 4831 or RL19 for the 180 gr and IMR or H 4350 may be other good choices.As for the 220 Sierra. There is RL22 data availible for the Sierra bullet. Work up to max loads with Rl22 and use that as your start load for RL25

I have some data, I just need to find it.

88.0gr. of RL25 200gr. Accubond - 3210fps
86.0gr. of RL25 220gr. Woodleigh - 3040fps
90.0gr. of RL25 185gr.. CoreLokt - 3345fps

Thank you, sorry about the delay. That 185 grain load is mighty impressive! I have a load worked up with imr-4831, I haven't ever chronographed it, but i use 76.0 grains. I should chrono it, but tell you what, the oal, everything, it just shoots. Probably not a hot load, but it gets her done. I just have some reloader 25 sitting around and want to use it.
Thank you for you help.

No problem. Good 8mm Mag data is really hard to find.