Keez,
I concur with your choice of bullets. Speer bullets are just enough tougher than most other cup/core bullets that they provide significantly increased terminal performance. When going for heavier game I would choose the Speer Mag-Tip or Grand Slam. In any case, for any animal, I would NOT use lightweight bullets.
I hope you find another 25-06 to replace the stolen one. That story broke my heart. I checked the Kimber website for you and found that their 8400 rifles in 25-06 have the 1:10" twist rate. I also checked the Remington site and the M700 CDL is the same, as is the Ruger M77R MkII. I gotta believe with all those manufacturers making their barrels 1:10" that they should be able to shoot the 120 grain Speer. I'm just glad that my new Ruger M77 MkII 6.5x55 has a rifling twist rate of 1:8" bacause 140 grains is the LIGHTEST bullet I want to shoot.
A buddy has a Rem 700 Sendero that was giving him troubles. I suggested working up to a load of 50 grains of IMR 4831 with the Speer 120 grain bullet. He tried it and was ecstatic! His gun now shoots 3/4" groups. The maximum charge in my Third Edition Hornady Handbook is 50.3 grains of IMR 4831 with the Hornady 120 grain Spire Point bullet. The Speer bullet should react very similarly. As always, start 5-10% below maximum and work up.
Best of good fortune to you in your quest for a good 25-06.
_
