284 is the bullet diameter and in the US can be a 7mm. Cartridge would be a 284 Winchester and it would depend on the maker and type of rifle you buy.
284
How much is a savage 7mm
no, the 7mm is .284 bore, the .338 is, of course, .338
check the .284 jarret rifle check the .284 jarret rifle
The 7mm designation is a reference to the bore size, or diameter. In decimal size it means this rifle has a barrel groove diameter of .284 inch.
Yes
Recommend you ask for assistance at your local gun shop.
10-1000 USD depending on specifics
Case length and bullet diameter. The 7mm Rem Mag uses a smaller diameter bullet (.284 vs .308) at higher velocity with higher pressures and more gun powder capacity.
You will have to state your intended use.
It it is a Winchester, you can find sn information at proofhouse.com.