I had this conversation with Steve Timm and this was his reply;
"Hey Jeff,
I've whacked no end of antelope, deer and a few elk with the .25-'06 and 100-grain Ballistics or 100-grain Hornady Interlockeds. Currently, I'm using 56.0 grains of RL-22 with Winchester cases and Winchester WLR primers. Muzzle velocity is 3,450 fps.
By the way, Nosler Ballistics, Nosler Partitions and Hornady Interlockeds, all of 100-grain weight, print the exact same point of impact in my barrel.
I'm sighted +2.5" @100 yards and cross over at 285 yards. Pretty much point blank to 360 yards and still hold into hair at 450. Helluva cartridge.
Frankly, I have never shot an animal twice with 100s in the .25-'06. Goats, deer and elk simply drop at the shot.
All the best,
Steve"
If anyone wants the article he sent me that he wrote for Varmint Hunters Magazine on the 25-06 just pm me your e-mail and I will send it. The article is a pdf file.
I would start at 54.5gr of RL22 and work up!