Superformance powder and the .257 Ackley Improved

[MT Pockets]

I am new to the .257 AI but have always wanted one. I now have mine built on a short action Remington model 7. It ports a No. 1 contour fast twist 20" barrel. I have fireformed new Nosler brass during my barrel break-in and am pleased with the accuracy but now want to load for this upcoming deer season. I selected a Speer 120gr. BTSP and IMR 4831 powder to start. I have less on hand than I had thought after fireforming and am curious as to Hogdon Superformance powder getting me in the velocity range I would like. I have no experience with this powder and hope someone here might and with .257AI experience would be a big plus.

 

[salmonchaser]

No experience yet but planning on sending off one of my #1 in 257 roberts for a new 257AI barrel. Will be following along.

 

[Dr. Vette]

I'll throw in some info on a similar-but-different cartridge.

I'm trying 140 Fusion in my 6.5 CM. The Superformance did not give me the accuracy I wanted at all, no matter what I tried.
I then swapped to StaBall 6.5 and it became incredibly accurate and I gained speed. I was shocked at the difference.

Personally I have not had great luck with the Superformance powder for any loading or cartridge so far.

 

[Blkram]

My QuickLoad version does not include data for the Superformance powder. (And it is a powder that I haven't tried yet to date.)

I have been researching the 257 AI Improved (or AII) of late after learning that Hornady may commercialize it with fast twist barrels, for a potential build next year. If they do, that means factory brass that will be properly head stamped, and ammunition. Although Quality Cartridge may also produce properly head stamped brass...like that which I got from them for my 250 AI. (I had to send them 3 fireformed cases from my rifle for them to ensure the proper case dimensions to provide me with the brass.)

The load data that I have gotten from QL for this potential build and 115-117 gr bullets has shown Re-26 to be an option, but this powder is pretty difficult to obtain at the moment. (Luckily, I have a good supply on hand.)

Other powders to try, according to my research are H-4831, StaBall 6.5 and Re-17 (also hard to obtain, and again I have a good supply on hand). But I have not run these through QL as yet.
CFE 223 might be another I need to look at, as it shows great potential for the 250 AI. (Just the velocities not as fast as Re-26, but faster than H-4350 and StaBall 6.5.)
Other powders that QL has showed good velocities (3000 -3100+fps) in the regular 257 Roberts with 117 gr bullets (SGK) are Re-16 (after Re-26), Hunter, Re-19, IMR 7828SSC, IMR-4831, and N560.

Sorry, I couldn't be of more assistance here.

What twist is your barrel?

 

[MT Pockets]

My QuickLoad version does not include data for the Superformance powder. (And it is a powder that I have tried yet to date.)

I have been researching the 257 AI Improved (or AII) of late after learning that Hornady may commercialize it with fast twist barrels, for a potential build next year. If they do, that means factory brass that will be properly head stamped, and ammunition. Although Quality Cartridge may also produce properly head stamped brass...like that which I got from them for my 250 AI. (I had to send them 3 fireformed cases from my rifle for them to ensure the proper case dimensions to provide me with the brass.)

The load data that I have gotten from QL for this potential build and 115-117 gr bullets has shown Re-26 to be an option, but this powder is pretty difficult to obtain at the moment. (Luckily, I have a good supply on hand.)

Other powders to try, according to my research are H-4831, StaBall 6.5 and Re-17 (also hard to obtain, and again I have a good supply on hand). But I have not run these through QL as yet.
CFE 223 might be another I need to look at, as it shows great potential for the 250 AI. (Just the velocities not as fast as Re-26, but faster than H-4350 and StaBall 6.5.)
Other powders that QL has showed good velocities (3000 -3100+fps) in the regular 257 Roberts with 117 gr bullets (SGK) are Re-16 (after Re-26), Hunter, Re-19, IMR 7828SSC, IMR-4831, and N560.

Sorry, I couldn't be of more assistance here.

What twist is your barrel?

I am very much encouraged by your reply. Thank you for all the info you shared. My twist is 7.5" as I plan to deer hunt with this rifle and have several better suited for varmints and such. As I have gotten older recoil seems to weaken my desire for long range sessions. My 7/08 and .280 are fine now but I am looking ahead. I can get through this season with my IMR-4831 but will begin more extensive attention to loads come Spring. Hopefully powder availability won't be an issue it is of ate. Stay in touch.

 

[Blkram]

I am very much encouraged by your reply. Thank you for all the info you shared. My twist is 7.5" as I plan to deer hunt with this rifle and have several better suited for varmints and such. As I have gotten older recoil seems to weaken my desire for long range sessions. My 7/08 and .280 are fine now but I am looking ahead. I can get through this season with my IMR-4831 but will begin more extensive attention to loads come Spring. Hopefully powder availability won't be an issue it is of ate. Stay in touch.

Nice. With that twist rate you should be good up to the 131 gr bullets, should you decide to go heavier than 120 gr. 1:7 is recommended for the 133-138 gr bullets.
While you may want to shoot longer distances, the higher BCs will help flatten trajectories at the longer distances. The other advantage on game will be the higher sectional density of the heavier bullets for added penetration capacity. While the 115 gr bullet has a SD of .249 (.250 being the recommended minimum for big game), they get better as you get heavier; 117 gr @ .253, 120 @ .260, 128 gr @ .277, and 131 gr @ .291.

I too find reduced felt recoil is just more enjoyable to shoot as I get older. After shoulder issues in the early 2000s I started to get more rifles with reduced recoil as they didn't bother the shoulder as much. After the shoulder got better and I could handle the recoil of my larger bores, I still found myself shooting and hunting more with less powerful cartridges. With my current shoulder injury from an accident this spring, it will be next year before I can start shooting again, and I'll be using the smaller, less powerful cartridges to start off with again. I look forawrd to getting nack to where the shoulder will handle the 9.3x62, 375 Steyr, and 416 Taylor, for future hunts.

I believe that we are all looking forward to Alliant being able to produce powder for us handloaders again!