Bought new rifle, Old Sako AV in 9.3 X 300 WM - 2967 FPS with 286 NPs

RL17 is a weird powder. Today I got 3250fps with a 175gr bullet from a 300WSM. No pressure signs whatsoever, even though it's nudging 300RUM velocity. Accuracy wasn't great though. Every time I use RL17 I basically get this result. Crazy high velocity, few pressure signs and inconsistent accuracy.. Probably good enough accuracy to hunt with, but other powders are much better in the same rifles.
 
Gatehouse, you are not the first guy I have heard that from, yet it gives very high velocity and fine accuracy in the one 308 Winchester I have developed loads for.

180s at 2795 fps, 3125 ft lb, primers starting to flatten, edges still round, bolt lifts easy, primer pockets still tight, no measurable head expansion after five firings.

Three shot groups average 7/8" at 100 yd. Other than a Krylon paint job, the rifle is a plain vanilla Stevens 200 with its factory 22" barrel.

Ted
 
Gatehouse said:
RL17 is a weird powder. Today I got 3250fps with a 175gr bullet from a 300WSM. No pressure signs whatsoever, even though it's nudging 300RUM velocity. Accuracy wasn't great though. Every time I use RL17 I basically get this result. Crazy high velocity, few pressure signs and inconsistent accuracy.. Probably good enough accuracy to hunt with, but other powders are much better in the same rifles.
Click to expand...

My experience has been exactly the same, best velocity in cases where 4350 works well but real sketchy accuracy. Doesn't matter I'm out of it now and there's been none in town for months.:mad:
 
I'll be heading to the range this weekend and do some more shooting with this rifle as well as others and checking zero and groups with my .375 H+H before heading off to Africa. I have 286 Parts loaded and I may load some more 270s as I got my WSS order and have another 4 boxes. Gonna try 4350 and Win 760 I think, still looking for that 3100 fps. Will post data and pics tomorrow night weather permitting.
 
Rembo said:
I would think velocities should be close to the 375 Taylor....a bit more case capacity but a bit smaller bore....where's Supercub?
Click to expand...
I got these velocities with my 375 early on in the testing. Extraction was easy and primers were not totally flat.

I don't need/want that kind of performance so I backed it off to 2700fps with 270 TSX. The moose I shot this year didn't seem to know the difference.

375CT2866fps.jpg
 
OK guys I'm back in the Yukon with my beloved toys and will be resuming my development of this cartridge and a few others I've procured over the winter...............stay tuned. I may just sight this baby in and go kill a bear tomorrow with it just to get her blooded. This thread is just too much fun (read contoversial) to let die just yet.
 
Good info in this thread, I gotta question for the OP though (sorry if I missed it) why base the 9.3 on a 300 win case vs. a 338 win case?

edit: thanks cam, I thought the case capacities were about the same, they are significantly better for the 300.
 
Last edited:
Well boys I took the 9.3X300 out and killed a nice black bear tonite, looks to score around 20" which is a big bear here. Will have pics and story tomorrow. I can tell you from this terminal ballistic experiment that the 270 gn Speer HC was not designed for impact velocities above 3000 fps. The bullet penetrated less than 12" of bear, hit the spine but had already fractured into several pieces.
 
Last edited:
You must log in or register to reply here.
Back
Top Bottom