Firing pin protrusion, 22-4

[robertrwalsh]

I am getting borderline "fizzles" with rounds from my 22-4 (frame mounted firing pin). Springs are factory stock, recently replaced. No obvious rub marks or interference on hammer. Compared to my other .45 ACP revolvers (not frame mounted) the firing pin protrusion appears to be marginal and maybe inadequate.

Can anybody tell me what the correct minimum firing pin protrusion thru the recoil shield is for this weapon? Thanks.

 

[Protocall_Design]

You want .050 out the front, the thickness of a dime. The minimum firing pin length is .495. Extended firing pins are around .505. Most factory firing pins are shorter than .495. You can take yours out and measure it.

 

[robertrwalsh]

Thanks Protocall Design. I have never removed one of those but I can't imagine it is that hard. I am intending to fill the Hillary Hole anyway so I can kill two birds with one stone.

 

[MG34/bar]

The last couple of J frames I got from the factory had marginal firing pin protrusion (about .030 as best I could measure) so I have a supply of longer firing pins from APEX that solves the problem. These are inexpensive and easy to install in place of the factory pins. I'm no gunsmith, so believe me if I can do it anyone can.

 

[Bullet Bob]

It's always helpful to give background information before making a conclusion. What type of ammunition was being used. Has more than one brand been tried. Were moonclips used. If so, what brand. That kind of information.

 

[robertrwalsh]

I went ahead today and pulled the old firing pin to install a new overlength one. The old factory stock one measured 0.484 overall. The new one protrudes noticeably further into the window. It measured about 0.505 overall. I intend to take it out later today and send a few rounds down range but I am guessing this will do the job.