I am with Jim Keenan, why, but if you want a Norma, consider this. It is a inherently accurate cartridge, you can get more velocity, with less powder, doesn't hurt the shoulder as much as a .300 Win. (at least mine don't). Have known 3 other people that had Norma's, 2 on Enfield actions, 1 on a 98 action. Unknown barrels, but all have shot well under 1" @ 100 yards.
Have never compared it to a .300 Win mag, but have to a .300 Weatherby Mark V (german). This comparison was done in the gunsmithing lab at Oregon Institute of Technology in the early '70's.
My rifle: .308 Norma mag.
Husqvarna HVA action
Douglas 26" XX barrel with 1/2 " freebore
Jaeger trigger
Roberts stock (lot of castoff & drop)
My load:
Sierra 180 gr. BT
77 grs. 4831 (original 4831)
WW .300 H&H brass
CCI 200 primers
Chrono. 5 rounds avg. 3127 fps.
No signs of pressure, good case life.
My friends rifle:
Weatherby Mark V
His load:
Sierra 180 BT
81 grs. 4831 (original), we split a 50 lb. keg.
Norma brass
CCI 200 primers
Chrono. 5 rounds avg. 3074 fps.
No signs of pressure, good case life.
Most of the load info for the Norma is going to be in a 24" barrel.
Might add, this rifle was built in "69 and still shoots 3/4 " groups, if I do my part.
Hope I didn't bore anyone, but, I love the cartridge!