280 AI and Retumbo

[DC125]

Hello,

I have a 280 AI in a 22” proof barrel. I am shooting 175 gr Berger EH with IMR 8133 at 2800 fps and can no longer find any more powder. Retumbo is as close as I can find on the burn rate chart but am not seeing the speeds I was getting with 8133. I am only at 60.5 gr and seeing no pressure signs but am at book max from what I can find online. I am getting 2650 fps, is that as good as I can get or would you try to squeeze a little more out of it? I would like to atleast get to 2700 fps if possible. All groups were around 1” with some getting down to 1/4” at 100 yds during testing.

Thank you

Dave

 

[NorCal 707]

You might try H4831, Staball 6.5 or if you really want some juice IMR7828, Reloader 23. I shoot the 175 EH at 2968 fps with Rldr 23.

 

[Sinistram]

What about the new StaBall HD? On the burn rate chart it's directly next to 8133. I hear good things.

 

[shmtastic]

My 22" savage UL 280AI does very well with staball 6.5, it's the first powder I try now. I think retumbo will be too slow for what you want, it took compressing it in the 7RM to get make it work for me.

 

[TheCoyote]

What about H1000? Too slow?

 

[The Guide]

Hello,

I have a 280 AI in a 22” proof barrel. I am shooting 175 gr Berger EH with IMR 8133 at 2800 fps and can no longer find any more powder. Retumbo is as close as I can find on the burn rate chart but am not seeing the speeds I was getting with 8133. I am only at 60.5 gr and seeing no pressure signs but am at book max from what I can find online. I am getting 2650 fps, is that as good as I can get or would you try to squeeze a little more out of it? I would like to atleast get to 2700 fps if possible. All groups were around 1” with some getting down to 1/4” at 100 yds during testing.

Thank you

Dave

This is the chart they sent to me when I asked for info on what to load the 175 with.

Jay

 

[NorCal 707]

What about H1000? Too slow?

No, H1000 does work but you just can't get enough of it in there. But its consistency and being not sensitive to temperature change makes it a top choice for heavier bullets. For a 22" barrel he really needs a faster powder, Reloader 17, 23, 26 or IMR 7828 ssc. Pretty certain Reloader 17 is gone with the Dodo birds. Staball 6.5 does pretty good with 160 grain projectiles. He should probably drop down to the 150 or 168 grain Classic Hunters and get the 2850-2900 fps and go huntin!

 

[jfk69]

Can’t speak to the .280 AI as I don’t own one. But N560 is incredible in my standard .280. Low spreads and single digit SD’s and velocity is solid. This is with 150-162 grain bullets though, so it might be a tick fast for the 175’s. Maybe 565 or 568 could be your huckleberry…

 

[DC125]

I have some H4831SC to try out and bought some 168 gr classic hunters as it lets me load to my lands. Was also going to try and increase the retumbo load a little to see if I can find another accuracy node before I run into pressure signs with my brass. I would be happy if I could break into the 2700 fps and am almost there.

Trying to stick with a powder that is easy to get as I do not want to find a powder that shoots good but is unavailable is becoming difficult. It seems like these powders are released in runs and reloading is more popular than ever, or the supplies are low.

Thank you for the suggestions and data.

Dave