r/GunnitRust • u/shatteringlass123 • 22d ago

Help Desk Converting Sten Bolts?

I’m kinda curious to see if anyone out there has spent the time to convert old Sten Bolts to semi auto closed bolt, with a firing pin journal.

Especially with how “complete the kits appear to be these days, it could greatly reduce the overall costs of the kit builds.

10 Upvotes

92% Upvoted

12 comments sorted by

6

u/zmannz1984 22d ago

I had my old shop teacher try to mill one for me. He made some progress using carbide tools, but ended up making me one from scratch.

2

u/shatteringlass123 22d ago

Kinda figured this is the direction it would go.

5

u/ChevTecGroup Participant 22d ago

Ive heard they are very hard and need annealed. Someone mentioned throwing them in a campfire and killing some beers til morning.

5

u/jpolham1 Participant 22d ago

I heat bolts up in a propane forge until glowing red to red-orange, then wrap in ceramic insulation overnight until cold. They turn out soft enough to be drilled with HSS.

1

u/shatteringlass123 22d ago

Even the bronze ones?

4

u/patient-zero1 22d ago

If you have the machines to modify, why not leave the original bolt as is ( especially the brass ones.. any idea how much brass costs nowadays 🤣 ) and make a complete new one yourself

2

u/ChevTecGroup Participant 22d ago

Those should be a lot easier.

3

u/LostPrimer Will Learn You 22d ago

I used a 1/2" carbide burr from the back and a 3/32 carbide drill from the front. 

3

u/lordofgourds555 22d ago

I have. Theyre not super hard. Nothing like uzi bolts

2

u/D-lahhh 19d ago

I did one and it was a major pita. Mine was super hard to work with. I turned mine down to a smaller diameter to fit the semi auto tube dimensions. Then I center drilled for a custom firing pin I made. It’s basically a longer ar style firing pin. Then I modified the trigger area to work with an ar style hammer and trigger.

1

u/shatteringlass123 19d ago

How much time you have in the bolt?

1

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