Re: 280 AI load
Thanks for the replies guys. I also emailed Hornady and asked them for a load and here is the responce I got from them. Im not sure they will work for me with the 1-10" twist but im gonna try them anyway.
The Hornady #2840 7mm cal. 162 gr. National Match A-MAX bullets were discontinued some years ago. This 7mm bullet has a whopping .710 BC that makes this bullet extremely flat shooting. You will need at least a 1-in-8" twist to 1-in-8 1/2" twist to really stabilize it. I have shot them out of my 1-in-9" twist 1000 yd. match rifles and these bullets do not stabilize quite as good as our present #28402 162 gr.
A-MAX bullets with the red polymer tip that have a .625 BC. Be sure to check your .280 Ackley Imp. barrel twist to make sure that it is between 1-in-8" twist and 1-in-9" twist. I would recommend 52.0 grs. to 53.0 grs. of H-4350 or 55.0 grs. to 56.0 grs. of H-4831SC. Start at least 1.0 to 2.0 grs. below what I gave you. If you have any load data for the .280 Rem. Ackley Imp. cartridge using a 160 gr. or 162 gr. bullet, I would recommend that you back off at least 5% and work up carefully.
The best to you in reloading, shooting, & hunting!
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