More chrono data on the 16.5" 300Mag

[PJ]

I have been trying to find the best powder for my new toy.I want the best velocity and most accurate load.I have used IMR4350 and IMR4064.I'm thinking W-760 maybe next..? If any of you have an idea let me know.Here is the run down so far....All loads grouped 1/2" to 1"

180gr Speer SBT
70grs IMR4350
2680fps

180gr Speer SBT
59grs IMR4064
2597fps

165gr Speer Spitzer
71grs IMR4350
2687fps

165gr Speer Spitzer
61grs IMR4064
2702fps

[Duffy]

You might try some VV N550 or N560. I found that the N550 in my 7-08 gave higher vel plus tighter groups. Varget was my best for vel but the accuracy sucked. 4064 gave good accuracy but no vel. The 4350 was just too slow for the 708. With the N550 I get 2625 fps from a 140g BT and about a .75 group if I do my part.  Sort of the Goldielocks syndrome.
Ryan

[PJ]

IMR4350 gives me more velocity with 180's than IMR4064.But IMR4064 gives me more velocity with 150's and 165's.The Speer SBT 150gr goes 2766fps and the 150gr XBT hit's 2818fps.Factory Rem Core-locks hit 2720fps and group 1".The 70gr 4350 load groups 1/2" as do the 165's.I'll try W-760 next.