The Firing Line Forums - View Single Post

Ignition Override · September 17, 2011, 11:23 PM

mkk41: Please correct me if any of this is wrong.

After I recently bought my Spanish FR8, the amount of confusion on the Internet about that rifle was impressive. It's my first .308/7.62 and I spent a few hours reading, just to sort things out. Confusion between the FR8 and FR7 is just one of a few issues, and many people believe anything that they hear or read.

A few guys included a chart, which claimed that conversion from 7.62 CUP to commercial psi allows an extra 8,000 factor to result in NATO psi equal to about 58,000.
Commercial ammo equates to about 62,000 psi, but the original proof pressures were far higher than both figures.

As a result, a difference of 4,000 psi seems negligible, and the FR8 action is the Spanish 8mm Mauser, which has much later, stronger steel than the Spanish 7mm Mauser ( year 1916?), on which the FR7 was built.

People often don't bother with buying a headspace gauge, and the Spanish 7mm Mauser converted to .308/7.62 NATO seems to be in serious need of either the Go/No go, or the field gauge.
Many long-term, knowledgeable Mauser fans are very wary of the conversions from the classic early 1900s 7mm to .308.7.62.

September 17, 2011, 11:23 PM	#8
Ignition Override Senior Member Join Date: February 18, 2008 Location: About 20 nm from the Big Muddy Posts: 2,887	mkk41: Please correct me if any of this is wrong. After I recently bought my Spanish FR8, the amount of confusion on the Internet about that rifle was impressive. It's my first .308/7.62 and I spent a few hours reading, just to sort things out. Confusion between the FR8 and FR7 is just one of a few issues, and many people believe anything that they hear or read. A few guys included a chart, which claimed that conversion from 7.62 CUP to commercial psi allows an extra 8,000 factor to result in NATO psi equal to about 58,000. Commercial ammo equates to about 62,000 psi, but the original proof pressures were far higher than both figures. As a result, a difference of 4,000 psi seems negligible, and the FR8 action is the Spanish 8mm Mauser, which has much later, stronger steel than the Spanish 7mm Mauser ( year 1916?), on which the FR7 was built. People often don't bother with buying a headspace gauge, and the Spanish 7mm Mauser converted to .308/7.62 NATO seems to be in serious need of either the Go/No go, or the field gauge. Many long-term, knowledgeable Mauser fans are very wary of the conversions from the classic early 1900s 7mm to .308.7.62.