UZI Bolt Info by jdb3 SMG top, semi bottom. Notice the difference in the ejection ports. The SMG has more rearward travel. It also does not have an extra spring (striker spring) like the semi. The port has been moved to the rear and flared to help with ejection. The original bolt feet will have to be moved and clearance added to the bolt for the different travel.
Left side. The striker bar clearance needs to be cut.
There isn't much playing room if you get the firing pin hole off, the dimension shown is just a quick measurement. Be careful and do some dimension checking on your end. Also note the relief in the rear of the SMG bolt. The SMG bolt has more rearward travel than the semi, the relief is for the stock nut. The striker dimensions will need to be altered because of this, or this area built up.
If using the hooded semi feed ramp, the bolt will need some clearance.
Another shot of the ejection port flare.
Here's the semi bolt with striker and buffer.
There's a difference in semi bolts also. Model A and Model B. Model B's use a firing pin safety. All Mini bolts use this also. This prevents full forward travel of the striker until the bolt is closed. It pivots off of the extractor pin and the timing is controlled by the ejector. Model A left, Model B right.
Model B with firing pin safety.
The ejector and safety relationship.
As the bolt passes over the ejector, it pivots. The "tail" on the rear lifts up and will allow the striker to travel fully forward.
Safety latch removed.
Safety latch cut in bolt.
The SMG ejector will need to be modified for semi auto use. The ejector on the right is an SMG ejector. I've already cut the rear clearance on this one, so don't let the picture throw you off. The angle cut is next.
