11 September 2009, 01:02
404WJJefferyAre the 7x51 and 7mm-08 same same?
Gentlemen
I am looking at a neat rifle marked 7x51 and read that is is the same as the 7mm-08??? Is the ammo interchangeable.
I fully recognize this may be an idiotic question, but thank you in advance.
11 September 2009, 01:17
cobraquote:
Originally posted by 404WJJeffery:
Gentlemen
I am looking at a neat rifle marked 7x51 and read that is is the same as the 7mm-08??? Is the ammo interchangeable.
I fully recognize this may be an idiotic question, but thank you in advance.
One and the same. No such thing as an idiotic question.

11 September 2009, 01:34
Dr. LouIt should be,but you may want to make a chamber cast to be sure there are no differences in shoulder angles or case taper, etc. Lou
11 September 2009, 04:19
Alberta Canuckquote:
Originally posted by Dr. Lou:
It should be,but you may want to make a chamber cast to be sure there are no differences in shoulder angles or case taper, etc. Lou

11 September 2009, 06:22
FjoldIt's a wildcat so you never know without a chamber cast. The 7.62x51mm chamber spec has .005" more headspace than the 308Win which may or may not make a lot of difference but you never know what a wildcatter will do.
11 September 2009, 07:59
404WJJefferyThanks to all for the information- I greatly appreciate it.
11 September 2009, 12:13
eagle27404WJJeffery I haven't heard of a cartridge called a 7x51. The 7mm-08 is based on the 308 Win case so has a 51mm case length. The early wildcat was called the 7mm-308.
Are you sure the marking on the barrel or receiver of the rifle is actually 7x51 and not 7x57 which of course is a different cartridge.
If it is marked 7x51 then a simple way to check for headspace with a 7mm-08 cartridge would be to stick a piece of thin foil on the case head and try chambering the round. If it is no go but will chamber without the foil then in all likelyhood the rifle is actually a 7mm-08.
Sounds a bit crude but then chamber casting will not give you the absolute answer either due to normally accepted chamber dimension variables in any cartridge.
11 September 2009, 20:57
stillbeemanFWIW my first 7-08 had barrel markings: 7mm-.308 not 7x51. I think I'd look again.