Thread: 7mm RM rechambering

Originally Posted by Grimus

Impressive data, thank you very much for that, and will definitely look into 7-300 NM too. I hadn’t planned on opening the bolt face, but that is definitely an easy option, especially seeing the info you’ve just given

I dont believe 300NM class cartridges will fit in Tikka action. The cartridge is closer in size to .338lapua. It certainly wont fit in a Tikka magazine.

7mm with the right projectile will generally have better ballistics than the .300s. The only mainstream .308dia projectiles im aware of that has a higher BC than the 7mm 180 ELDM are the Hornandy 230 and 250gr A-tip projectiles, which only just edge out the basic (and cheap) 180ELDM. Hornady have not yet published the BCs for the new 7mm A-tips, but I have no doubt they will easily top the best BC 30cal projectiles commonly available.

The other thing to keep in mind is the twist rate of the standard barrel. It may not be sufficient for the heavy 7mm's.
The added velocity will offset some of the lack of twist rate, but will it be enough? Im not sure...would be borderline id think. (if we are talking 180ELDM)