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Slamfire · January 25, 2013, 09:37 AM

I have more slamfire posts on Garands than any other mechanism, but combined, the posts on all other mechanisms, including M1a’s, M1 carbines would be at least as long, but I thought the posting of them redundant.

Now one thing I note from your posts, and all of your posts that I have seen on this subject, is a lack of discussion or acknowledgement of primer sensitivity. That is something I have noticed from shooters from “back then”. They only attributed causes are mechanical, shooter misconduct, high primers. And yet, the elephant in the room is primer sensitivity. It has always been the elephant in the room, it has always been known.

That is why people have been told to feed from the magazine or to use SLED’s. It is to reduce the kinetic impact of the firing pin on the primer. I find it humorous that primer sensitivity deniers give this advice without making the connection why this advice is good.

It is also why most designs with free floating firing pin have springs around the firing pin. I know from a member of an Armalite design team, that their AR10’s were tested with military LR ammo, without a firing pin spring, and the rifles slamfired. So Armalite put the firing pin spring in the mechanism.

There are very good later designs have features that radically reduce the chances of an out of battery slamfire, a failure mechanism that has plagued Garand type mechanisms since day one. Even the Russians put in design features that reduce the chance of an out of battery slamfire as you can see in this video from Murray’s Guns.

http://www.youtube.com/watch?v=xj3QtnUWCwQ

I think what Murray did was crazy dangerous, but if you managed to wedge a Garand type firing pin in the forward position, such as Murray did with the SKS, you would blow it up.

The Garand mechanism was one of the first semi automatic military rifles, the M14 is a product improved Garand, but the mechanism dates back to the 20’s and back then Americans accepted death and dismemberment as a normal employment risk.

If you notice, AR’s don’t slamfire out of battery, neither do HK91’s. These are 50's vintage designs. In fact, HK91’s don’t have firing pin initiated slamfires. There are very good reasons for that. The Germans designed out that possibility by putting a firing spring so stiff that it takes two hands to compress the bolt.

January 25, 2013, 09:37 AM	#26
Slamfire Senior Member Join Date: May 27, 2007 Posts: 5,261	I have more slamfire posts on Garands than any other mechanism, but combined, the posts on all other mechanisms, including M1a’s, M1 carbines would be at least as long, but I thought the posting of them redundant. Now one thing I note from your posts, and all of your posts that I have seen on this subject, is a lack of discussion or acknowledgement of primer sensitivity. That is something I have noticed from shooters from “back then”. They only attributed causes are mechanical, shooter misconduct, high primers. And yet, the elephant in the room is primer sensitivity. It has always been the elephant in the room, it has always been known. That is why people have been told to feed from the magazine or to use SLED’s. It is to reduce the kinetic impact of the firing pin on the primer. I find it humorous that primer sensitivity deniers give this advice without making the connection why this advice is good. It is also why most designs with free floating firing pin have springs around the firing pin. I know from a member of an Armalite design team, that their AR10’s were tested with military LR ammo, without a firing pin spring, and the rifles slamfired. So Armalite put the firing pin spring in the mechanism. There are very good later designs have features that radically reduce the chances of an out of battery slamfire, a failure mechanism that has plagued Garand type mechanisms since day one. Even the Russians put in design features that reduce the chance of an out of battery slamfire as you can see in this video from Murray’s Guns. http://www.youtube.com/watch?v=xj3QtnUWCwQ I think what Murray did was crazy dangerous, but if you managed to wedge a Garand type firing pin in the forward position, such as Murray did with the SKS, you would blow it up. The Garand mechanism was one of the first semi automatic military rifles, the M14 is a product improved Garand, but the mechanism dates back to the 20’s and back then Americans accepted death and dismemberment as a normal employment risk. If you notice, AR’s don’t slamfire out of battery, neither do HK91’s. These are 50's vintage designs. In fact, HK91’s don’t have firing pin initiated slamfires. There are very good reasons for that. The Germans designed out that possibility by putting a firing spring so stiff that it takes two hands to compress the bolt. __________________ If I'm not shooting, I'm reloading.