25-06 Load Development

[Bbear]

One of mine loves/loved the 120 gr Speer BTSP with IMR 4831 behind it. Shot itty-bitty bugholes with that load. Switched over to 110 AB's (which are as rare as Unicorns) and one liked RL-19 and the other liked H4831 in a medium speed load.
Now playing with some RL23 and RL 26 just to see what they can do. Using those two powders with the 117 Sierra GK. Now all I need is some range time.

 

[BretN]

Harv,

Your gun is already telling you what OAL it likes to shoot Partitions. I'd start with the same length as those factory loads you are getting sub MOA results with. If you have to, you can always work closer to the lands.

I spent a long time trying to get my 280 to shoot well with loads that were .010" off the lands because that's what the books and the internet knowledge suggested I should do to start. Several different bullets just wouldn't give decent accuracy doing that, including 140 gr AB. Then I was in a hurry to try a new bullet and just loaded it to the book length and it shot great. Tried the 140 AB at .050" off the lands and it shot into a .36" cloverleaf group. So now I start with the book length, which usually has plenty of jump and modify from there. Bret

 

[BretN]

Re-read your post more carefully and see that you did exactly what I suggested with same OAL as the factory partitions. Then you probably just gotta tinker with powders. You could pull apart a factory round and note what type of powder (spherical or extruded) and weight and try to duplicate that. RL19 was the powder I was using in my 280 when I got that great group. No idea how it works in a 25-06, as I don't have that caliber (yet). I really like how well RL19 meters though. IMR 4350 works great in my 280 and 30-06 as well. Good luck with it.