Forgotten Weapons does the Uzi
- Thread starter Gaujo
- Start date
Jtm35a2
UZI Talk Life Member
It has always bewildered me how people will pay more for a registered receiver with blocking bar than a registered slotted bolt.
The registered receiver with blocking bar is the worst of every possible scenario. No caliber changes, no spare bolts, can’t move the bolt to other hosts. It has to be the absolute worst possible way to convert an uzi.
The registered receiver with blocking bar is the worst of every possible scenario. No caliber changes, no spare bolts, can’t move the bolt to other hosts. It has to be the absolute worst possible way to convert an uzi.
Good video covering the two basic conversion methods, but there were other things that people did. Some registered the receiver and then slotted the bolt instead of removing the blocking bar. That shouldn't have happened but people did it because it was easier. When they did, the modified bolt is "married" to the receiver, making it just a restrictive as having a registered bolt and giving you even less flexibility. Another conversion route was to register the bolt and then add a lower lip to the semi-auto bolt instead of slotting a full auto open bolt. In that case, you had a conversion that ran very fast (because it was closed bolt) and no way to slow it down. Also very undesirable. And there are a small number of registered sears, which require other modified parts (like a slotted bolt) so all the modified parts are "married", taking away much of the flexibility of the gun. Bottom line is that a properly converted registered receiver with the blocking bar removed is the most flexible option, most like the original UZI SMG, and demands the highest price. You get all of that out of the box with the Vector UZI, but in exchange for a receiver that's out of spec and has sometimes caused problems until it's repaired.
APEXgunparts
Well-known member
Question, on a registered receiver UZI that still retains the blocking bar, what is the challenge with having a machine shop mill the bar out?
I assume it is plug welded into the receiver.
Richard
I assume it is plug welded into the receiver.
Richard
navgunner
UZI Talk Life Member
Yes, the bar is simply plug welded into the receiver.
As a manufacturer, here’s my understanding. Others, please chime in if I’m wrong or missing anything.
If you were to remove the blocking bar from a registered receiver UZI then according to the Feds you’d have two machine guns because of the slotted bolt. In theory you could destroy the slotted bolt and then remove the blocking bar but when I asked the ATF if I could provide this as a service, I got an abrupt “no”.
In one of Richard Hoffman‘s videos, he explained something similar but if there was a situation where a blocking bar was already damaged/destroyed then he could remove however, I haven’t come across a situation personally.
AKarms
Well-known member
He does make some mistakes in his last uzi video about the function of the micro Uzi and there was another mistake I forget on the mini possibly. But he does put out good stuff, always watching
AKarms
Well-known member
Yea it’s a straight up no. If they were registered with the blocking bar that’s where she stays
AKarms
Well-known member
It’s not a challenge. It’s not legal. Atf doesn’t allow it under any circumstances from my chats with them
Read the top section on receiver conversions.
It seems ATF considers a registered receiver conversion with the blocking bar intact and a slotted bolt making a new machine gun if you knock the bar out of your registered machine gun receiver.
For example say you back in the day registered an M16 lower receiver but instead of drilling the auto sear hole you took one of those infamous supposedly grandfathered unregistered drop in Auto Sears from shotgun News and installed it. Technically you have a semi-automatic spec registered machine gun receiver and an unregistered conversion device. So you take the DIAS and melt it into slag with your cutting torch. You still have a registered receiver machine gun.
So now you take that semi-automatic spec lower receiver to your shop and drill the pin hole. What you now have according to ATF is a registered machine gun receiver that was papered in 1984 but since you turned it into a machine gun in 2025 you have now made a new machine gun! Despite the fact that before you touched it with tools it was legally a registered machine gun receiver.
A legally registered transferable machine gun receiver, that is also an illegal machine gun receiver.
Wrap your mind around that one. The classic Trek episode I, Mudd would have been over a lot earlier if they had Norman access the computer records for ATF decisions! His fried Android brain would have been spouting illogical illogical like a broken record two seconds after.
It seems ATF considers a registered receiver conversion with the blocking bar intact and a slotted bolt making a new machine gun if you knock the bar out of your registered machine gun receiver.
For example say you back in the day registered an M16 lower receiver but instead of drilling the auto sear hole you took one of those infamous supposedly grandfathered unregistered drop in Auto Sears from shotgun News and installed it. Technically you have a semi-automatic spec registered machine gun receiver and an unregistered conversion device. So you take the DIAS and melt it into slag with your cutting torch. You still have a registered receiver machine gun.
So now you take that semi-automatic spec lower receiver to your shop and drill the pin hole. What you now have according to ATF is a registered machine gun receiver that was papered in 1984 but since you turned it into a machine gun in 2025 you have now made a new machine gun! Despite the fact that before you touched it with tools it was legally a registered machine gun receiver.
A legally registered transferable machine gun receiver, that is also an illegal machine gun receiver.
Wrap your mind around that one. The classic Trek episode I, Mudd would have been over a lot earlier if they had Norman access the computer records for ATF decisions! His fried Android brain would have been spouting illogical illogical like a broken record two seconds after.
APEXgunparts
Well-known member
I love the reference to the original series Star Trek!
Another question, has anyone approached the ATF with this question this year?
A lot has changed, new ATF leadership, new legal counsel, import rules have changed, the DOJ has supported pro 2A cases.
From what I am seeing the ATF is trying to undo a lot of stupidity that was pushed out in the past 30 or so years.
It would take a carefully worded question from a company licensed to repair NFA items, such as milling out the blocking bar so a factory bolt can be fitted.
Just a thought, since this is the time.
Richard
He was referring to a registered receiver that still has the blocking bar, which requires a slotted bolt, but that bolt isn't the registered part the receiver is. Two parts are married, even if you could divorce them the only registered part is the receiver not the bolt.
Jtm35a2
UZI Talk Life Member
Some builders marked the bolt too. I had a Fleming sear mini. Sear, receiver, and bolt were marked.
Fact of the matter is that moving the bolt to another host is creating a non registered machine gun. Just like if the bolt ever failed for some crazy reason, making a replacement is also creating a non registered machine gun.
Hence why the registered receiver with blocking bar is the 100% worst possible type of uzi to buy. And is why i think they should be 25% less than registered bolt Uzi’s.
But alas, as Americans, we have the right to do stupid things.
In practice, someone with a full size registered UZI bolt rarely moves it to a different host, so I consider a registered bolt and a registered receiver that still has a blocking bar/married bolt to have equal functionality, so I'd price them the same.
Jtm35a2
UZI Talk Life Member
I reckon everyone has their opinion. I just look at versatility, when there’s the option to do so. And when there are options that allow versatility, they should be priced higher than a one trick pony.
Although I think we have a similar view that registered receiver with blocking bar should not be more expensive than a registered bolt.There are sellers, and buyers falling for it, that price registered receivers with blocking bar the same as those without. I have to imagine that there’s alot of regret once they figure out how limited they are.
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