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tangolima · January 5, 2014, 08:47 AM

I agree with Slamfire as I did the test on my M1 and M1 carbine and am convinced.

The bridge only protects the rifle against slam fire during, or slightly before, the bolt cams down in the receiver. If the cartridge stops before that, because of obstruction or what not, the firing pin will strike the primer and out-of-battery slam fire is possible. Military spec primer should therefore be used.

A few things to add
1. The firing pin is not quite inline with primer all the time. The round needs to come out of the magazine and go into the chamber about half way before the primer lines up with the firing pin hole.

2. It is a push-feed action. The cartridge stops and the extractor snaps over the cartridge's rim, then the firing pin can reach the primer. This decelerates the bolt gradually and lessens the free floating firing pin's energy.

-TL

January 5, 2014, 08:47 AM	#8
tangolima Senior Member Join Date: September 28, 2013 Posts: 3,827	I agree with Slamfire as I did the test on my M1 and M1 carbine and am convinced. The bridge only protects the rifle against slam fire during, or slightly before, the bolt cams down in the receiver. If the cartridge stops before that, because of obstruction or what not, the firing pin will strike the primer and out-of-battery slam fire is possible. Military spec primer should therefore be used. A few things to add 1. The firing pin is not quite inline with primer all the time. The round needs to come out of the magazine and go into the chamber about half way before the primer lines up with the firing pin hole. 2. It is a push-feed action. The cartridge stops and the extractor snaps over the cartridge's rim, then the firing pin can reach the primer. This decelerates the bolt gradually and lessens the free floating firing pin's energy. -TL Last edited by tangolima; January 5, 2014 at 10:11 AM.