What causes a failure to fire?

[beagler]

I've read a lot about certain pistols having a failure to fire. I realize it could be the primers, but what other causes could there be. I would think this would be mostly an ammo issue and not the gun. Any input?

 

[grislyatoms]

Causes could include:

Firing pin spring too stiff
Primer seated too deep
A burr or such in the firing pin channel slowing or otherwise obstructing the pin
Wrong firing pin (too short)
Firing pin not returning all the way (meaning the hammer can't hit it properly)

That's all I can think of off the top of my head.

 

[Geronimo45]

Everything Grislyatoms said, plus leprechauns.
If debris is in the firing pin channel, it can cause that to happen.

 

[benEzra]

Primer has no priming compound (ammo manufacturing defect).

The only FTF I've ever had with my 3913LS was apparently one of those.

 

[Bobo]

I'll add...

A weak or broken hammer or striker spring.

 

[Phil DeGraves]

I will add that striker fired pistols (GLOCK, M&P, XD) and rebounding hammer pistols (SIG) will experience more FTF than other systems if ammo with hard primers are used, such as the non-toxic or lead-free (CCI & Blazer Cleanfire, Federal NT) variety. This conclusion is from watching ten years of LE training with all types of pistols. Generally, these rounds will fire when struck a second time; also the problem corrects itself when regular leaded primers are used.