5.56 in a Rem .223 rifle

[entropy]

I thought it was a pretty simple question. Very very few rifles are chambered specifically as 7.62x51, and any such made in the US is made to SAAMI standards, for which 308win and 7.62x51mm are identical.

So which rifle do you have, in particular, which is stamped as 7.62x51 and made outside of the US?

FR8's would be an example.

 

[MechAg94]

FR8's would be an example.

There were some Ishapore Enfield rifles that were imported back in the 2000's that were chambered in 7.62X51. I don't think you typically see it on US made rifles.

 

[Varminterror]

There were some Ishapore Enfield rifles that were imported back in the 2000's that were chambered in 7.62X51. I don't think you typically see it on US made rifles.

This was my point.

A vast majority of non-AR US made rifles chambered for 223rem shouldn’t be fired with 5.56 ammo, even US made 5.56 ammo. Whereas alternatively, an even more dominating majority of rifles made anywhere in the world are made with 308win chambers, such 7.62x51mm ammo is safe. It’s rare to find a 7.62x51mm for which 308win would actually be above the design pressure for the chambering, while it’s exceptionally common to find 223rem chambered rifles in which 5.56 ammo would be above the design pressure.

So relating the two comparisons really isn’t apt. One comparison is like comparing men’s and women’s shoe sizes - a men’s 9 will fit a size 9 woman’s foot, but a woman’s 9 won’t fit on a man’s size 9 foot. While the other comparison is more like comparing horseshoes to men’s shoes - if you happen to be a horse, you need horse shoes.