CMMG firing pin life expectancy?

[bradaz11]

does it look like this?



if yes, where did it break?

[safetyfirst]

Mine broke at the 90 degree step every single time.

[bradaz11]

Mine broke at the 90 degree step every single time.

would machining that step flat, then drill a hole down, and insert a hardened pin into that (ala home made punches etc) not make for a better design? what sort of dia are we looking at?

[safetyfirst]

Nice idea. Want me to get the callipers out on Monday?

[Gazza]

It broke here....

[DL.]

That's appalling. Did they not do any research and development before they launched those rifles onto the market?

[dromia]

Lot of discussion about it here:

https://www.full-bore.co.uk/viewtopic.p ... firing+pin

Seems like an ongoing issue that the manufacturers see fit to ignore.

[bradaz11]

Nice idea. Want me to get the callipers out on Monday?

well as long as you have around 1mm of side wall I would think it would be good enough. the tailstock on my lathe isn't great atm (lathe project is taking a backseat til I actually can think of stuff to make and get some decent size material - like some 3" plastics, anyway), but for the accuracy needed i reckon a face cleanup and then chuck it in a decent drill press would get a good enough result.

If sizes are about right, I wonder if it would be worth tapping it and using a cut down stainless screw? either that or might find some sort of hardened pin available online.
This sounds a bit amateur, but i'd try first to just glue it in with something like PVA, that would probably move with it, but not hold it in too hard. It only needs to overcome the inertia of the bolt afterall??

[Gazza]

I think Mr Paa should make a few quid from a redesign/material change of this pin.
So Dave, on it this week coming?
Put me down for at least one maybe two

I've been looking at titanium rod on Evilbay and it seems quite reasonable ( I always thought it was super expensive stuff)
Most of it seems to be grade 5 ??? is that the good stuff?

[bradaz11]

I think Mr Paa should make a few quid from a redesign/material change of this pin.
So Dave, on it this week coming?
Put me down for at least one maybe two

totally agree, but if a bit of home machining can get it back in action for now, while you wait for the Shed to free up some space for a more permanent fix, where's the harm?

it's already snapped off, what will drilling a hole in it do to make it worse?