Registered F/A closed bolt durability?

[chead]

I've been thinking of doing an NFA trust with a buddy and putting a registered closed bolt on it. My only concern is durability.. do they kaboom? Do the welds need to be assessed often? If it did kb, would it destroy the receiver? Kill me?

This is not intended to be practical or a competition bolt, and a high ROF would just be fun at the range. But I don't want to spend a lot if it will need repair.

 

[Glockdude1]

Kaboom?

Maybe with bad reloads from someone that did not know what they were doing.

If you are referring to a Uzi welds, the Uzi outlast you. Not to mention the mountain of money you would need to spend on ammo, just to begin to crack a Uzi weld.

:surfing

 

[chead]

Fair enough! The idea of a welded lip kinda freaks me out but I suppose welded steel is pretty well strong enough

 

[EagleArmsHBAR]

How is a closed full auto bolt different from a semi bolt?

 

[tacdrivrnc]

it has a reinforced lower lip like an open bolt, and it does not have the blocking bar cut. It may or may not be relieved for a semi-auto trunnion, depending on the style of original bolt (FA or semi) and amount of machine work done to it. IIRC registered closed bolts are hard to find.

 

[EagleArmsHBAR]

I'm confused. How would a full lip around the boltface make it go full auto?

 

[Glockdude1]

I'm confused. How would a full lip around the boltface make it go full auto?

The lower lip on the bolt will not make the Uzi fire full auto. It allows the bolt to close, and then allow the firing pin to fire the loaded round. It is all part of the "timing" of how a Uzi works in full auto.

Semi Uzi's don't need the lower lip on the bolt.

:surfing

 

[EagleArmsHBAR]

Is there a video or something that explains the timing? I'd like to learn more.

 

[chead]

If its runnin full auto, especially at such a high ROF as would be the case with a closed bolt in full auto, without the lower lip it's going to jam quickly. There are two types of registered closed bolts: Conversions from a registered open bolt (which have the lip already present) and semi closed bolts that have the supporting lip of the bolt face welded up. I'm asking about the welded up semi bolts specifically since if I wanted an open bolt I would just buy one. The conversion from open to closed makes more sense when someone already owns a registered open bolt (and probably multiple) as far as I know.

 

[chead]

Why are registered closed bolts hard to find? Just because people were buying/making open bolts before '86? And owners aren't inclined to convert them to closed? Do the fetch higher prices than open bolts?

 

[EagleArmsHBAR]

Does a closed FA bolt use a semi sear or FA sear? Also, besides the lip are the dimensions of the FA closed bolt the same as the semi bolt?

 

[Glockdude1]

http://c3junkie.com/

All your questions will be answered here. Go to "Uzi Information".

:surfing