'Thought I'd get some expert advice on powder here. Over the years I've tried lots of different powders as the " latest and greatest" came out, but finally gave up about 3 years ago and went back to using my old reliable IMR 4350 exclusively because it was, without exception, the most accurate powder in every load tested over 50gr. A guy at sierra said I wasn't as much of a dinosaur as I thought because a lot of bench rest guys had done the same and that IMR4350 was also the least temperature sensitive powder they (Sierra) tested. Any opinions about this?
If Hogdon fiddles with IMR 4350 then go to Accurate XMP-4350 I use the same loads with either and can't tell any difference between them. They are both very accurate powders. So is H-4350 but the load data is different.
I have used it for 25 yrs and is a good powder. I started out using it in the .270 Win and when I got my first 7mmRM that was my first choice. Accuracy was top notch. Over the years other powders have come along and I've tried quiet a few of 'em.
I drifted away from IMR4350 in the 7mag when I got my first Sendero in that cal. I started using RL22 and verlocity and accuracy was great. I eventually shot the barrel out and traded it for the 700P that I have now.
I have found that it doesn't like 168 Bergers or RL22. I tried quiet a few powders in this rifle and had almost convinced myself to trade it in and get something different.
Then I tried IMR4350 with the 150gn BT and there it is. Bam! Sub-1/2" and 3240fps. I haven't seen anything run away from it. JohnnyK.
I went to R19, R22, and R25 for 7mm mag loads, but none of the loads were as accurate as IMR 4064 and IMR 4350. Also for 270 WSM, IMR 4350 performed better with 130gr accubonds than R19 or R22. Did quite a bit of testing with the WSM.
R22 has worked great for 270 Win, but haven't tried any other powder since R22 did so well.