Wanted: a solution to the Reising SMG firing pin breakage problem.

[Frank I.]

I have posted this on several forums for maximum exposure. 

The most common failure on Model 50-55 Reising submachine guns is broken firing pins.

There are a lot of smart and skilled individuals in the class III community.  The community needs one of these individuals to design and manufacture a Reising SMG firing pin that will last for at least a few thousand rounds.

Original steel firing pins are impossible to find; the only new manufacture pins available are those made of titanium. I cannot get one to last more than 500 rounds before the tip breaks off.  

There have been some semi-successful advancements, like the inertia modification described in the link below. In my experience, the inertia modification works best with original steel firing pins, the titanium pins not so much. 

The inertia firing pin thread (unfortunately, the photos are gone)

https://www.machinegunboards.com/forums/index.php?/topic/8854-paulfs-pictorial-guide-to-how-i-made-my-reising-run-great/

 There is another individual on machinegunboards.com who was doing some experimenting I have pasted a link to his thread. On his last post, he had not yet been successful.  

https://www.machinegunboards.com/forums/index.php?/topic/29557-new-to-me-reising-new-to-me-firing-pins/

[StrangeRanger]

Frank,

I'm 99% certain that Cort's design is dimensionally as good as it can get.  He has addressed all the problems with the initial design and the Keystone rework. All that remains is to sort out the correct alloy and the heat treating but that can be a trip down the rabbit hole.  Fatigue proof is basically 1144 which is strong, readily machinable and easily heat treated but it doesn't contain any nickel or molybdenum both of which improve impact resistance.  I'm guessing that his planned reduced hardness trial of S7 which is specifically designed for impact resistance or possibly 4140 or 4340 both of which are very good alloy steels is going to be the final answer.  The devil is going to be balancing impact resistance vs. brittleness