New firing pin different look

[cRuffy]

Got new firing pin today in mail. Correct number from the rep. Gave him serial number. Does anyone have this firing pin. The old one on bottom. New on top. Looks same but does anyone here have the new one like this. The rep said the pins fit all 15 22

 

[cjt50]

My newer 15-22 has the top one. No issues, getting very deep hits on the rim.

 

[cRuffy]

Bolt assembly same ?

 

[cjt50]

Eyeing the parts quickly, yes, they appear the same.

 

[MarkBrumbaugh]

I think the old one was guilty of slam firing and the newer one is shorter, only protrudes by inertia. Correction, the early problem was OOB ignition, not necessarily slam fire. Pardon my brain fart.

 

[cRuffy]

Fill me in. What is protrudes by inertia.

 

[Gunslinger808]

Momentum from the hammer strike propels it out of the bolt face to hit the rim of the cartridge.

 

[cRuffy]

I was upset when I got the pin because it looked wrong. But these pins look like hard steel.

 

[roushstage2]

I think the old one was guilty of slam firing and the newer one is shorter, only protrudes by inertia.

Fill me in. What is protrudes by inertia.

If my understanding of slam fire is correct, inertia is what would cause it, not prevent it. A spring around the firing pin would prevent a slam fire (and the 15-22 has one). Free-floating firing pins (AR-15, M1 Garand, SKS) are the ones that could have slam fire issues. From what I've read, the early 15-22s could have OOB discharges.

 

[Majorlk]

If my understanding of slam fire is correct, inertia is what would cause it, not prevent it. A spring around the firing pin would prevent a slam fire (and the 15-22 has one). Free-floating firing pins (AR-15, M1 Garand, SKS) are the ones that could have slam fire issues. From what I've read, the early 15-22s could have OOB discharges.

An inertia firing pin does not protrude from the bolt face until the force of the firing pin spring is overcome. Non-internia (free floating) pins will protrude from the bolt face if one simply presses on them.

That said, most slam fires are not caused by free-floating firing pins; they simply don't have sufficient force to strike the primer without being hit by the hammer/striker. They are sometimes caused by a too-long firing pin protruding from the bolt face, but the most common cause is a dirty firing pin channel in the bolt, not allowing the firing pin to retract. In other words operator error cause by lousy maintenance.

 

[roushstage2]

An inertia firing pin does not protrude from the bolt face until the force of the firing pin spring is overcome. Non-internia (free floating) pins will protrude from the bolt face if one simply presses on them.

That said, most slam fires are not caused by free-floating firing pins; they are sometimes caused by a too-long firing pin protruding from the bolt face, but the most common cause is a dirty firing pin channel in the bolt, not allowing the firing pin to retract. In other words operator error cause by lousy maintenance.

Ah, OK. He was talking about the type of pin then. I've not heard them called inertia and non-inertia pins before. I was reading it literally: inertia itself (physics).

As for the second part, I'm not personally sure what causes most slam fires. These are all things I've read about; I've never experienced or personally seen a slam fire. I know the AR-15 can mark the primer on a chambered, but not fired, round. That's the extent of my knowledge on the subject.

Back to the topic at hand: the 15-22 hasn't been commonly known to slam fire, has it (talking about the need for a new firing pin design to address the [potential] problem)?

 

[Majorlk]

Back to the topic at hand: the 15-22 hasn't been commonly known to slam fire, has it (talking about the need for a new firing pin design to address the [potential] problem)?

Not that I am aware of.

 

[MarkBrumbaugh]

If my understanding of slam fire is correct, inertia is what would cause it, not prevent it. A spring around the firing pin would prevent a slam fire (and the 15-22 has one). Free-floating firing pins (AR-15, M1 Garand, SKS) are the ones that could have slam fire issues. From what I've read, the early 15-22s could have OOB discharges.

In an inertial pin, the pin cannot extend past the bolt face except during the firing when the momentum is transferred to the pin. The old pins were longer and the pin was longer than the bolt and extended when the hammer was against the bolt face. The newer pin is shorter. At least that is what I understood. So my understanding is opposite the above. In any case my pin is new and inertial. I somewhat researched this when I had 100% ftf until I disassembled the pin, cleaned and smoothed off some artifacts from the pin. Others with better knowledge, chime in.

 

[MarkBrumbaugh]

In an inertial pin, the pin cannot extend past the bolt face except during the firing when the momentum is transferred to the pin. The old pins were longer and the pin was longer than the bolt and extended when the hammer was against the bolt face. The newer pin is shorter. At least that is what I understood. So my understanding is opposite the above. In any case my pin is new and inertial. I somewhat researched this when I had 100% ftf until I disassembled the pin, cleaned and smoothed off some artifacts from the pin. Others with better knowledge, chime in.

Perhaps is was not a slam fire problem, but early models had OOB firing, destruction of ejector, etc., leading to the shorter pin.