Slam Fire model 81

[Samk1983]

I picked up a model 81 on GB a few weeks ago and completely tore the receiver and bolt down for a deep cleaning before heading to the range. I noticed in my disassembly that my model 81 is equipped with a 2 piece firing pin which I’m starting to believe I assembled incorrectly. I am having a hard time finding videos or diagrams of how the bolt is assembled with the firing pin.

After a few hours of battling through the assembly process I got it all back together and headed to the range. I loaded one round in the magazine and let the bolt slam home and boooommmm the gun went off safely down range. This is obviously not ideal and needs some serious attention.

Im also having issues with the bolt not staying locked back, any help would be greatly appreciated.

[Hibby83]

Hello Sam.

Sorry to hear about your issue. I'm sure that you don't plan on taking to the range until some bench testing is done, PLEASE consider that rifle unsafe for range use until you remedy the issue and do your testing safely.

Are you using reloaded ammunition? Does the rifle appear original, or possible that there's been replacement parts/been fooled with? Have you installed any new parts in the rifle that may need fitting for proper operation?

I've only encountered the 3 piece firing pin once, it was in a spare replacement bolt carrier group that I picked up a few years ago. I kind of doubt if the firing pin came with that bolt carrier that it could be assembled wrong. Does the firing pin tip have a rounded end or does it appear to be pointed? Does the firing pin appear to stick out TOO far when the hammer is down with the bolt carrier forward "you can see this with the rifle taken down, bolt carrier must be forward and the hammer must be also." I will have to pull my 2 piece pin "group" out of the spares* box, inspect and report back.

Does your bolt not lock back at all under any circumstances "how strongly you pull back bolt handle," or some of the time?
Multiple components can attribute to bolt lock problems. The magazine spring indicator has a part in the locking back, which is supported by how well the magazine spring is pushing up on the magazine follower "which engages a small piece of the indicator assembly."

[Hibby83]

Your firing pin looks like this?

[Samk1983]

Hibby,

When I initially took my bolt apart I didn’t take the rear pin out to look at the 2nd “rear” part of the 2 piece firing pin. Once I encountered the slam fire issue I took the bolt completely apart and found that the firing pin is broken. I’ll post pics after a bit. I’ve since ordered a new firing pin and springs. I’m hoping that fixes my issues.

[Samk1983]

Hibby

[Hibby83]

Thanks for sharing a photo.

Yours is only the second picture "counting mine" that I've seen of the 3-piece firing pin. It's talked about in the Henwood book 3rd edition page #54.

[Samk1983]

Hibby,

Can you show me or have a diagram of a standard firing pin assembly? I’m not finding much anywhere. I hope to get my new firing pin and springs this week. I hope there isn’t any hand fitting required.

[Hibby83]

Sam.

I don't have a diagram to show. Once you get the new 1 piece firing pin, it should come together fairly easy.

First install the firing pin into bolt carrier. Appropriately line up the retention gap on firing pin, slide in pin "from the top" that retains firing pin to bolt carrier. Firing pin should freely move back and forth without binding "in it's limited range of travel." Get your bolt and extractor lined up, install cam pins.

Report back to group with questions. There's a couple youtube videos that cover assembly/disassembly that help.

[Tucsontony]

IMG_0654-compressed.jpeg (723.04 KiB) Viewed 4716 times

Item 32

[Hibby83]

https://thegreatmodel8.net/?page_id=1855

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