Home Forums Reloading Big Game Rifles Powder choice for 280 Ackley IMP Loads

I'm having a custom built in a 280 Ackley Imp. Taking a quick invitory of powder on hand, I have four powders I could possibly start with to work up a load to get things started. R17, R26, H4831SC and possibly H4350.

I can get more R22 easily but with the temp instability issues people seem to have with this powder in the 280 Ackley IMP, I have decided to search elsewhere for an accuracy load.

Does anyone have any experience with any of these powders? If so, what kind of velocity and accuracy are you getting? What is your load recipe. I thought of trying the H4350, R17 in the 140gn Nosler BT. H4831sc or R26 with the 150 ABLR, or the 168 Bergers. Suggestions or helpful recommendation would be great.

H4350 is spectacular in my .280AI (23 inch barrel) with the 120 grain Nosler BT. 3325 fps velocity and sub one half MOA accuracy.

IMR 7828 shines with the 162 grain AMAX. 2850 ish on velocity and the same accuracy as the 120.

I use RL22, and always have, in the AI and the standard 280. Never once had temp issues that were significant enough to mean anything.

If I was starting from scratch, I might try RL23 for the added benefits. 26 might be a little bulky and slow for that cartridge.

Not sure that RL17 will have any less temp problems than 22 does, actually. I did run some H4350 with 120 grain loads, but stopped using that bullet. I just use one bullet and powder for everything now in the AI, and it works perfectly. 145 LRX.

I can get some 7828 as well, but would like to see what happens with the powders on hand before adding anymore to my invitory.

Like what Im hearing with the 120's but to be honest, 120gn is more on the light side of what I want to shoot. I hear they strike like lightning though.

Im really hoping I can get possitive results out of the Bergers. The Hunting VLDs have performed very well on whitetails for me. Almost like flipping a switch.

130 to 150 gr bullets in 270
140 to 175 gr bullets in the 280 (or AI version)
165 to 190 gr bullets in the 30-06

H4831 is the perfect burn rate for all. Lots of choices are nearly as good, none better.

If I can get the 150gn ABLR to fly like I want with good accuracy at 3000 fps I will be happy.

That shouldn't be a problem out of a 26 inch tube with H4831SC. I think nosler list that powder as their most accurate for the 150gn weight class bullets. Velocity looks to be right there where I want it, but to be honest I figured it would be a little higher. I will stop where I find the accuracy node. Hopefully accuracy and desired velocity will be there. If not I'll try something different.

H4831sc

RL22 in 2-280AI's using 140NP running at 3200 fps. very accurate but if I could get my hands on some 23 and 26 I would also try those powders as well.

I'm growing more interested in R26 the more I read about it. Hopefully someone with experience between this powder and caliber combo will chime in and tell us their results.

There is a thread on here about RL26 in the 280AI. Currently on page 6 of this forum

Looks promising. Would like to have seen a little more detail. If all else fails, I should be able to make something happen with H4831SC.

Running 7828 under 160 NP in my Kimber, right at 1/2 moa.

Mine loves H-4831sc from 140gr. to 162gr. bullets , although the Broughton barrel shoots great with Re-17 - H-1000 - I-7828ssc .
Day in day out consistently good groups = H-4831sc
, no chronograph -sorry .

Keep hearing good things about the H4831SC so i guess it's a good thing I have plenty of the stuff.

On a different note, what kind of velocity are you seeing out of a 26 inch barrel with the 168gn bergers. When I say bergers I mean the 168gn classic hunter. Those and the 150gn accubond LR Im most interested in.

mine shoots bugholes with 150 BT and 150 scirocco and H4831SC.

Ever clock any of those cecilb ?

I haven't had a chance except for 1. 59 grains went 2850. I'm sure i can use a couple more grains. I just wanted something to hunt with, so I chose a middle of the road load.

RL-22 pushes 175 gr partitions to a very accurate 2840 fps in my Montana.

I'm on my second AI. I've shot 140 grain BT's most the time the last 30 years, but switched last year to 150 grain LRAB's and Ballistic Tips. The LRAB's were real ticky about seating depth and I was able to get better groupings with the 150 grain BT's (.081" three shot group!). My rifle prefers RL-19 in both 140 and 150 grain loadings. In the past, I've used IMR-4831 as my go-to powder, as well as RL-22, with excellent results. I shot out three barrels in my first Jarrett AI culling does (legally). Each new barrel preferred 4831 or 22, with one barrel preferring RL-15...I'm not kidding. My new Jarrett is RL-19 all the way. Have not had a single AI rifle show a preference for either 4350, which I always thought was strange.

Good luck with your rifle!

I'd be sure and at least TRY the Re26. I'm playing with it in a plain .280 and have seen amazing velocity pushing 150 Partitions. Unfortunately my load development has been on hold for over a month, so I cannot declare that it will deliver the kind of accuracy I've seen with H4831, but I am optimistic. It's certainly worth a try, though, IMO.