The Firing Line Forums - View Single Post - 7mm-08 Load Data puzzle

Jimro · September 19, 2012, 09:30 PM

The "magnum primer" for ball powders is an interesting topic. Several years ago the military found that normal primers in M80 ball ammunition could have a slight "delay" in lighting off WC846 powder.

This was a concern for use in electric motor driven miniguns used on some aviation platforms. The firing rate is so high that a delay could be disastrous. So the primer was changed to the current milspec "magnum" primer.

So there you have it, a standard primer will light off ball powder, but there can be a delay measured in microseconds. Some folks who hunt in the cold report failures to ignite, but I haven't any first hand data or .gov reports to fall back on for that.

Jimro

September 19, 2012, 09:30 PM	#8
Jimro Senior Member Join Date: October 18, 2006 Posts: 7,097	The "magnum primer" for ball powders is an interesting topic. Several years ago the military found that normal primers in M80 ball ammunition could have a slight "delay" in lighting off WC846 powder. This was a concern for use in electric motor driven miniguns used on some aviation platforms. The firing rate is so high that a delay could be disastrous. So the primer was changed to the current milspec "magnum" primer. So there you have it, a standard primer will light off ball powder, but there can be a delay measured in microseconds. Some folks who hunt in the cold report failures to ignite, but I haven't any first hand data or .gov reports to fall back on for that. Jimro __________________ Machine guns are awesome until you have to carry one.