Home Forums Reloading Big Game Rifles Cooper Model 52 in 280AI reloading

Recently purchased a Cooper M52 in 280 Ackley and was curious if anyone has experience with shooting 160 or heavier hunting bullets in theirs. The test target is incredible but was shot with a 130 SMK.
Thanks Jim

Still at 50 yards and indoors?

Yes.

I’m sure the rifle is waaay more capable than I am. Just looking for some help.
Thanks Jim

Take the bullet and powder from the target look up the start load for that. Probably a Sierra bullet. 9 times out of 10 that start load is what they shot the target with. My pair of 223’s were shot with a 50 Blitzking using 24 grs. H335. My 220 Swift was shot with a 50 BlitzKing and 39 grains H380 both new and a 2nd tube.
If you call they might tell you specifics. But I’m betting it will shoot, but it’s up to you as too what and how after that.
My Swift was finicky at times the other 2 weren’t, but they are still different in multiple ways.

Thanks Swifty.

Looks like about 4-5 powders show up in that Flavor from Sierra in heavier bullets. 4350’s of course, magnum, but RL 22 - 25. seems to be the huckleberry for all but the 130.

I've shot the 280 AI for nigh on 35 years. With 140 and 150 grain Noslers my rifles have preferred RL-19, IMR-4831 and one even liked (loved) RL-15. IMR-4350 is also a preferred powder per the experts but I have never had a 280AI that even remotely liked it. Nevertheless, I'd give it a try too....you might hit a home run with it.

Good luck! PM me if I can help in any way.

I'd give RL26 a try with 160's and heavier bullets. I just tried some test loads with the 162 ELD-X in a standard 280 and the accuracy is there. I need to make up some more and chrono them. Here is some Speer data for the standard 280 should be a good starting point.https://www.speer-ammo.com/reloading/rifle/recipe/?setId=80629bc2-a933-4e59-b755-3cdcf2730a77

Thanks for all the replies. I currently have H4350, 4831SC and R16. 162 ELDX and 168 classic hunters as well.

63 gr N165 does 3200 with 140’s in my 280 AI

Care to share your load data? I have been working up a load for my .280, with the ELD-X 150 gr. bullet and RL- 26. So far, the accuracy and velocity are excellent- Sub-MOA groups and a MV of 3020 fps. I backed off the max load I have tried, not because it showed signs of pressure, but QuickLoad indicated it as a Near Maximum load.

I'm also shooting the 150 ELDX over 63.3 grains of RL26 in my 280AI. Velocity is 3120 fps. I've had great success with RL22 & RL23 in the 140 class bullets. For 150 and heavier I'd certainly be giving RL26 a try.

Thx again for sharing. Jim