280 AI owners

muzz · Mar 27, 2014

All you 280 Ackley owners here post up your load info. I just took my rifle down to get rechambered. What powder, speed, and groups are you getting.

I have two pounds of magpro, two pounds of retumbo. Anything else worth trying? I might get some 7828ssc and give it a go.

I have heard reloader 17 is another good one amongst others. I want speed ad accuracy and that will come for testing loads. its a factory barrel with 1-9 twist and im going to shoot the barnes 140 TTSX bullet.

O--one
B--big
A--ass
M--mistake
A--america

Stonefly · Mar 27, 2014

Had a 280 AI a few years ago sold it, and went with a 7mm mag. F$^&*#FIN Stupid move. Now I'v got rid of the Mag and am planning on building a new 280 AI soon. My old home rolled was IMR 4350 55.5 grns Sierra game king 140. My old Rifle was a madeover 7mm express and had a 24" barrel. I have written in my reloading note book " 5 shots- 1-3033fps 2- 3038fps 3-3033fps 4-3029fps 5-3031fps avrg 3032.8 . Cant wait to get back at it when I get my rifle done. allot of new powders and bullets to play around with. I really like the looks of the OVER .5 BAL. COEF. stuff, they have out now. If I remember the Sierra was mid .4ish. Will be cool to buy store bought brass, I fire formed all my old ones. would be nice to have you post up your findings good luck

sageadvice · Mar 27, 2014

I worked up to a max load a few years ago using IMR 4350. We found sweet groups with 59 1/2 grains pushing a 140gr noster bullet at 3250 FPS, about max or a bit beyond with that powder in my Pac Nor barreled Rem 700.

Joey

"It's all about knowing what your firearms practical limitations are and combining that with your own personal limitations!"

Zeke · Mar 27, 2014

LAST EDITED ON Mar-27-14 AT 08:31PM (MST)[p]My brother is building one but I have no first-hand knowledge of loads except to say that Retumbo and 7828 seems a bit slow burning for the case capacity of that cartridge. Maybe MagPro is even a bit slow. 17, 19, 22, 4350 or 4831 would seem like the logical choices.
The 140 TTSX Barnes is a great choice on big game. My kids and I have used Barnes in everything from .257 to .338 and love them, even 400 gr .416's.
Just my 2 cents,
Zeke

sheephunter · Mar 28, 2014

My best load in my Kimber is 62 grains of H4831 SC and a 140 grain triple shock. Usually 2 of the 3 in a 3 shot group are touching. It's a Mountain Ascent with a light barrel. Took a while to find the right load.