AR 10 firing pin strangeness

[232593]

I have two AR10s that have scratching on the sides of each pin. One of the pins is from JP Rifles (High pressure bolt, firing pin, & retainer pin set). The other is from a MILSPEC BCG. The rifles that they are used on are chambered in 22CM & 6.5 CM. 22CM is coming up on 200 rounds and the 6.5 has about 400 rounds through it

I disassembled some AR15 BCGs and found no scratches on the sides of their firing pins, despite them having a much higher round count.

Is this going to be an issue later and if so how is the problem fixed?

Lucas Oil CLP has been used on both rifles.

Any assistance would be greatly appreciated.

Thank you for your time

 

[bfoosh006]

I have two AR10s that have scratching on the sides of each pin. One of the pins is from JP Rifles (High pressure bolt, firing pin, & retainer pin set). The other is from a MILSPEC BCG. The rifles that they are used on are chambered in 22CM & 6.5 CM. 22CM is coming up on 200 rounds and the 6.5 has about 400 rounds through it

I disassembled some AR15 BCGs and found no scratches on the sides of their firing pins, despite them having a much higher round count.

Is this going to be an issue later and if so how is the problem fixed?

Lucas Oil CLP has been used on both rifles.

Any assistance would be greatly appreciated.

Thank you for your time

Can you post some pics ?

 

[bigjake83]

Assemble your BCG without the firing pin then line up the firing pin on the outside of the BCG right where it would naturally sit inside if it was assembled, this will give you a general idea going by the locations of the scratches on the firing pin where it's making contact.

You have four suspects, Bolt, Carrier, Cam Pin, Firing pin retainer.

If the "scratches" are located in the bolt remove the extractor and inspect for foreign material.

 

[232593]

Can you post some pics ?

Sorry about that I forgot to snap some pics. I’ll post some when I get off work tonight.

 

[232593]

Assemble your BCG without the firing pin then line up the firing pin on the outside of the BCG right where it would naturally sit inside if it was assembled, this will give you a general idea going by the locations of the scratches on the firing pin where it's making contact.

You have four suspects, Bolt, Carrier, Cam Pin, Firing pin retainer.

If the "scratches" are located in the bolt remove the extractor and inspect for foreign material.

Thank you for that. I will do that as soon as I get to the house tonight.

I’ve never had this happen before so I don’t know, do you think the firing pins are structurally compromised now?

 

[bigjake83]

Thank you for that. I will do that as soon as I get to the house tonight.

I’ve never had this happen before so I don’t know, do you think the firing pins are structurally compromised now?

Depending on the severity of these scratches but if it's just a surface scratch then no they will be just fine I would also make sure they are not bent by rolling them on a flat surface like a piece of glass.

We will know more once you provide pictures.

 

[232593]

Both firing pins 6.5 on the left, 22CM on the right

Close up of the scratches on the pin on the right

 

[232593]

Assemble your BCG without the firing pin then line up the firing pin on the outside of the BCG right where it would naturally sit inside if it was assembled, this will give you a general idea going by the locations of the scratches on the firing pin where it's making contact.

You have four suspects, Bolt, Carrier, Cam Pin, Firing pin retainer.

If the "scratches" are located in the bolt remove the extractor and inspect for foreign material.

Seem to be either the cam pin or inside the bolt. But I didn’t see any burrs inside either.

 

[msgriff]

I'd look for sharp edges at the firing pin hole through the cam pin.

 

[232593]

I'd look for sharp edges at the firing pin hole through the cam pin.

That’s what I was figuring but I’m not seeing anything so far. I’ll try again tomorrow in the daylight if I get home in time.