What can cause firing pin failure?

[jeeper2269]

rifle brand new, out of box. Take it to range and fire about 150 rounds. A couple rounds fail, and it appears the firing pin doesn't strike the primer hard enough. There is a light dent on the primer, so I figure, it must be the ammo, not the brand new rifle. Take it to range a fw weeks later, and same thing happens. The rifle was not cleaned at this point.

Couple weeks go by and the rifle is cleaned, but left dry. We go to the range again, again the same thing happens. Only this time, its much worse. Now I am sure it is the rifle. What do you guys think the problem is?

[ForTehNguyen]

hammer spring maybe out of spec and doesnt have enough spring force to dent the primer all the way. Get ahold of a known working lower and fire control group and a working firing pin and troubleshoot.

[TX Rancher]

Also, take a look at the firing pin travel and make sure it's moving freely over the entire range. Garbage obstruct the pin and cause problems.

Of course this is assuming the pin itself has not been damaged...

[Belmont31R]

Change out the cheapest parts first, and try to narrow down the problem. AND make sure what you already have installed is in correctly.



No offense intended but if you have to ask this question Im going to assume you don't know much about the AR....but there are lots of things that can cause this.



Start first with a new firing pin, then bolt with new pin, then entire BCG, and isolate the problem.

[ForTehNguyen]

maybe even check if the hammer spring isnt installed backwards

[Lincoln7]

Find a friend who knows their way around an AR look it over. It will probably be obvious to someone familiar. Also, your AR will be happier if you run it wet instead of dry.

[polymorpheous]

There seems to be a lot of missing information here.

Who makes the rifle?
Who makes the ammo?

[Iraqgunz]

The first thing you need to do is reveal some more information about your weapon, ammo, etc... as someone pointed out.

Then you need to ensure that the lower receiver is correctly assembled. Is the BCG assembled properly? Make sure that the firing pin is straight, and that moves freely inside of the bolt.

Is the BCG going into battery correctly everytime? If you know someone with a similar AR set up, I would do the following;

1. Put your entire upper receiver group onto a different lower receiver and see what happens. If it functions w/o problems then you can assume that something is wrong with your lower.

If it doesn't work, then I would start thinking about trying to measure the firing pin protrusion.

2. Use the other upper and drop it onto you lower. If it malfunctions then I would think that your lower is out of spec. At this point you need to think about changing the hammer spring. If it still doesn't work then I would think it's time for a new lower.

By doing the above you are checking the upper and lower both to narrow down the issues.

This all assumes that you are using correct and quality ammunition and magazines and that it is properly lubed.

[jeeper2269]

ammo was

remington 223

and

american eagle 556

both have failed.

Thank you for the info.

[jeeper2269]

Find a friend who knows their way around an AR look it over. It will probably be obvious to someone familiar. Also, your AR will be happier if you run it wet instead of dry.

I have a buddy in special forces. He saw the rifle before it started failing, and broke it down in about five seconds in front of me. I was really surprised, and remember him checking the firing pin then. He said it was running properly at that time, however, this was prior to failure.

I do not take offense to any comments made. I just need some advice. I will not post the brand until I have gone over the matter with them in detail first. I do not feel it would be fair to call them out like that.

[kmrtnsn]

ammo was

remington 223

and

american eagle 556



Dude, you have to do better than this. Details! You give mush info; you get mush answers to your questions. How about some bullet weights, part numbers, the exact type and manufacturer of the weapon.

Lube the thing up and follow IG's advice. Sounds to me like operator error combined with a dry, new weapon.

[MistWolf]

Did you inspect anything? Did you remove the firing pin & check to see if it's bent or broken? Did you check the firing pin protrusion? Did you check to see if the hammer swings freely? Did you check to see if the springs are set correctly? Did you check to see if the headpace is too long?

Basic troubleshooting must be performed to determine what condition(s) exist to keep the rifle from firing. You the shooter must perform the troubleshooting

[Iraqgunz]

Please don't take this the wrong way. Just because your buddy is in "SF" it doesn't mean that he knows whether or not the lower receiver is assembled correctly.

Check the things that were pointed out or contact the manufacturer first since you don't want to reveal anymore information. Once you have done that we'll open this thread back up and you can update us.


I have a buddy in special forces. He saw the rifle before it started failing, and broke it down in about five seconds in front of me. I was really surprised, and remember him checking the firing pin then. He said it was running properly at that time, however, this was prior to failure.

I do not take offense to any comments made. I just need some advice. I will not post the brand until I have gone over the matter with them in detail first. I do not feel it would be fair to call them out like that.