How to change uzi barrel?

1. Remove the magazine.  Pull back the bolt with the cocking knob on the top cover and visually inspect the chamber and bolt face for cartridges.

4.  Remove the striker assembly from bolt, but leave striker spring attached

5. Depress the barrel nut retaining latch.

6. Unscrew the barrel retaining nut and pull out the barrel.

8. Reassemble in reverse order.  Your Uzi is now ready to star in an 80’s action movie or take part in Operation Wolf.

The Uzi ( /ˈuːzi/ (listen); Hebrew: עוזי, romanized: Ūzi; officially cased as UZI) is a family of Israeli open-bolt, blowback-operated submachine guns and machine pistols first designed by Major Uziel "Uzi" Gal in the late 1940s, shortly after the establishment of the State of Israel. It is one of the first weapons to incorporate a telescoping bolt design, which allows the magazine to be housed in the pistol grip for a shorter weapon.

The Uzi prototype was finished in 1950. It was first introduced to Israel Defense Forces (IDF) special forces in 1954, and the weapon was placed into general issue two years later. The IDF supplied Uzis to rear-echelon troops, officers, artillery troops and tank crews, as well as a frontline weapon by elite light infantry assault forces.

The Uzi has been exported to over 90 countries.[14] Over its service lifetime, it has been manufactured by Israel Military Industries, FN Herstal, and other manufacturers. From the 1960s through to the 1980s, more Uzi submachine guns were sold to more military, law enforcement and security markets than any other submachine gun ever made.[17]

The Uzi uses an open-bolt, blowback-operated design, quite similar to the Jaroslav Holeček-designed Czech ZK 476 (prototype only)[18] and the production Sa 23, Sa 24, Sa 25, and Sa 26 series of submachine guns. The open bolt design exposes the breech end of the barrel, and improves cooling during periods of continuous fire. However, it means that since the bolt is held to the rear when cocked, the receiver is more susceptible to contamination from sand and dirt. It uses a telescoping bolt design, in which the bolt wraps around the breech end of the barrel.[19] This allows the barrel to be moved far back into the receiver and the magazine to be housed in the pistol grip, allowing for a heavier, slower-firing bolt in a shorter, better-balanced weapon.[17]

The weapon is constructed primarily from stamped sheet metal, making it less expensive per unit to manufacture than an equivalent design machined from forgings. With relatively few moving parts, the Uzi is easy to strip for maintenance or repair. The magazine is housed within the pistol grip, allowing for intuitive and easy reloading in dark or difficult conditions, under the principle of "hand finds hand". The pistol grip is fitted with a grip safety, making it difficult to fire accidentally. However, the protruding vertical magazine makes the gun awkward to fire when prone.[19] The Uzi features a bayonet lug.[20]

The non-reciprocating charging handle on the top of the receiver cover is used to retract the bolt. Variants have a ratchet safety mechanism which will catch the bolt and lock its movement if it is retracted past the magazine, but not far enough to engage the sear. When the handle is fully retracted to the rear, the bolt will cock (catch) on the sear mechanism and the handle and cover are released to spring fully forward under power of a small spring. The cover will remain forward during firing since it does not reciprocate with the bolt. The military and police versions will fire immediately upon chambering a cartridge as the Uzi is an open bolt weapon.

There are two external safety mechanisms on the Uzi. The first is the three-position selector lever located at the top of the grip and behind the trigger group. The rear position is "S", or "safe" (S = Sicher or Secure on the MP2), which locks the sear and prevents movement of the bolt.

The second external safety mechanism is the grip safety, which is located at the rear of the grip. It is meant to help prevent accidental discharge if the weapon is dropped or the user loses a firm grip on the weapon during firing.

The trigger mechanism is a conventional firearm trigger, but functions only to control the release mechanism for either the bolt (submachine gun) or firing pin holding mechanism (semi-auto) since the Uzi does not incorporate an internal cocking or hammer mechanism. While the open-bolt system is mechanically simpler than a closed-bolt design (e.g. Heckler & Koch MP5), it creates a noticeable delay between when the trigger is pulled and when the gun fires.

The magazine release button or lever is located on the lower portion of the pistol grip and is intended to be manipulated by the non-firing hand. The paddle-like button lies flush with the pistol grip in order to help prevent accidental release of the magazine during rigorous or careless handling.

When the gun is de-cocked the ejector port closes, preventing entry of dust and dirt. Though the Uzi's stamped-metal receiver is equipped with pressed reinforcement slots to accept accumulated dirt and sand, the weapon can still jam with heavy accumulations of sand in desert combat conditions when not cleaned regularly.[21] The magazine must be removed prior to de-cocking the weapon.

There are different stocks available for the Uzi proper.[22] There is a wooden stock with a metal buttplate that comes in three similar variations that were used by the IDF. The first version had a flat butt and straight comb and had hollows for a cleaning rod and gun oil bottle. The second had an angled butt and a straight comb and no hollows. The third had an angled butt and curved comb and no hollows; a polymer version is currently available from IMI. The wooden stocks originally had a quick-release base but the ones sold in the United States often had a permanent base for legal reasons, as detachable stocks on pistols or other short-barreled weapons upgrade the weapon to NFA status.[23][24]

Choate made an aftermarket polymer stock with a rubber butt-pad that had a flat butt, a straight comb, and a permanent base.

In 1956,[25] IMI developed a downward-folding twin-strut metal stock with two swivelling sections that tuck under the rear of the receiver. The Mini Uzi has a forward-folding single-strut metal stock that is actually an inch longer than the Uzi's. Its buttplate can be used as a foregrip when stowed. The Micro Uzi has a similar model.

The original box magazines for the 9mm Uzi had a 25-round capacity. Experimental 40- and 50-round extended magazines were tried but were found to be unreliable. A 32-round extended magazine was then tried and was later accepted as standard. The Mini Uzi and Micro Uzi use a shorter 20-round magazine. Available extended magazines include 40-, and 50-round magazines. Other high-capacity aftermarket magazines exist such as the Vector Arms 70-round and Beta Company (Beta C-Mag) 100-round drums.

The .45 ACP Uzi used a 16- or 22-round magazine, while the .45 ACP Micro Uzi and Mini Uzi used a 12-round magazine. A conversion kit by Vector Arms allowed the .45-caliber Uzi to use the same 30-round magazines as the M3 "Grease Gun".[26]

The Uzi was available with caliber conversion kits in .22 LR or .41 AE. The operator just has to change the barrel, bolt and magazine. The .22 LR had 20-round magazines; the original IMI kit used a barrel insert while the aftermarket Action Arms kit used a full replacement barrel. The .41 AE also had a 20-round magazine; since it has the same bolt face as the 9×19mm Parabellum, only the barrel and magazine needed to be changed.[26]

IMI also manufactured a .45ACP conversion kit both in full auto/open bolt with a 10.2" barrel for the 9mm SMG and a semi only/closed bolt with a 16" barrel for the carbine version. Magazine capacity is limited, with 2 sizes of 16 and 10 rds each.

The Uzi submachine gun was designed by Captain (later Major) Uziel Gal of the Israel Defense Forces (IDF) following the 1948 Arab–Israeli War. The weapon was submitted to the Israeli Army for evaluation and won out over more conventional designs due to its simplicity and economy of manufacture. Gal did not want the weapon to be named after him, but his request was ignored. The Uzi was officially adopted in 1951. First introduced to IDF special forces in 1954, the weapon was placed into general issue two years later. The first Uzis were equipped with a short, fixed wooden buttstock, and this is the version that initially saw combat during the 1956 Suez Campaign. Later models would be equipped with a folding metal stock.[21]

The Uzi was used as a personal defense weapon by rear-echelon troops, officers, artillery troops and tankers, as well as a frontline weapon by elite light infantry assault forces. The Uzi's compact size and firepower proved instrumental in clearing Syrian bunkers and Jordanian defensive positions during the 1967 Six-Day War. Though the weapon was phased out of frontline IDF service in the 1980s, some Uzis and Uzi variants were still used by a few IDF units until December 2003, when the IDF announced that it was retiring the Uzi from all IDF forces.[27] It was subsequently replaced by the fully automatic Micro Tavor.

In general, the Uzi was a reliable weapon in military service. However, even the Uzi fell victim to extreme conditions of sand and dust. During the Sinai Campaign of the Yom Kippur War, IDF Army units reaching the Suez Canal reported that of all their small arms, only the 7.62 mm FN MAG machine gun was still in operation.[28]

The Uzi proved especially useful for mechanized infantry needing a compact weapon, and for infantry units clearing bunkers and other confined spaces. However, its limited range and accuracy in automatic fire (approximately 50 m (160 ft)) could be disconcerting when encountering enemy forces armed with longer-range small arms, and heavier support weapons could not always substitute for a longer-ranged individual weapon. These failings eventually caused the phasing out of the Uzi from IDF front-line assault units.[27]

The Uzi has been used in various conflicts outside Israel and the Middle East during the 1960s and 1970s. Quantities of 9 mm Uzi submachine guns were used by Portuguese cavalry, police, and security forces during the Portuguese Colonial Wars in Africa.[21]

Total sales of the weapon to date (end of 2001) has netted IMI over 2 billion US dollars, with over 90 countries using the weapons either for their armed forces or in law enforcement.[17]

The standard Uzi has a 10-inch (250 mm) barrel. It has a rate of automatic fire of 600 rounds per minute (rpm) when chambered in 9mm Parabellum; the .45 ACP model's rate of fire is slower at 500 rpm.[21]

The Mini Uzi is a smaller version of the regular Uzi, first introduced in 1980. The Mini Uzi is 600 mm (24 in) long or 360 mm (14 in) long with the stock folded. Its barrel length is 197 mm (7.8 in), its muzzle velocity is 375 m/s (1,230 ft/s) and its effective range is 100 m (330 ft). It has a greater automatic rate of fire of 950 rounds per minute due to the shorter bolt. Its weight is approximately 2.7 kg (6.0 lb).[21]

The Micro Uzi is an even further scaled down version of the Uzi, introduced in 1986. The Micro Uzi is 486 mm (19.1 in) long, reduced to 282 mm (11.1 in) with the stock folded, and its barrel length is 117 mm (4.6 in). It has a closed bolt compared to its original counterpart.[32] Its muzzle velocity is 350 m/s (1,100 ft/s) and its cyclic rate of fire is 1,200 rpm. It weighs slightly over 1.5 kg (3.3 lb).[21]

The Uzi Pro, an improved variant of the Micro Uzi, was launched in 2010 by Israel Weapon Industries Ltd. (I.W.I.), formerly the magen ("small arms") division of Israel Military Industries. The Uzi Pro is a blowback-operated, select-fire, closed-bolt submachine gun with a large lower portion, comprising grip and handguard, entirely made of polymer to reduce weight; the grip section was redesigned to allow two-handed operation and facilitate control in full-automatic fire with such a small-sized firearm. The Uzi Pro features four Picatinny rails, two at the sides of the barrel, which can be removed, one below the barrel for the addition of foregrips and one on the top for optics. The under barrel rail is often shown with a specialised foregrip which attaches to the pistol grip to form a hand guard. In addition, the cocking handle has been moved to the left side.[33] The new weapon weighs 2.32 kg (5.1 lb) and has a length of 529 mm (20.8 in) with an extended stock,[34] and 300 mm (12 in) while collapsed. As of 2011 it has been purchased by the IDF in limited numbers for evaluation and it is yet to be decided whether or not to order additional units for all of its special forces.[34][35]

The Uzi carbine is similar in appearance to the Uzi submachine gun. The Uzi carbine is fitted with a 400-millimetre (16 in) barrel, to meet the minimum rifle barrel length requirement for civilian sales in the United States. A small number of Uzi carbines were produced with the standard length barrel for special markets. It fires from a closed-bolt position in semi-automatic mode only and uses a floating firing pin as opposed to a fixed firing pin.[28] The FS-style selector switch has two positions (the automatic setting was blocked): "F" for "fire" (semi-auto) and "S" for "safe". Uzi carbines are available in .22 LR, 9mm, .41 AE, and .45 ACP calibers.

The Uzi carbine has two main variants, the Model A (imported from 1980 to 1983) and the Model B (imported from 1983 until 1989). The Type A was the same as the fully automatic Uzi, while the Type B had a firing pin safety and improved sights and sling swivels. These two variants were imported and distributed by Action Arms.[28]

The American firm Group Industries made limited numbers of a copy of the Uzi "B" model semiauto carbine for sale in the US along with copies of the Uzi submachine gun for the U.S. collectors' market. After registering several hundred submachine guns transferable to the general public through a special government regulated process, production was halted due to financial troubles at the company. Company assets (including partially made Uzi submachine guns, parts, and tooling) were purchased by an investment group later to become known as Vector Arms. Vector Arms built and marketed numerous versions of the Uzi carbine and the Mini Uzi.[36]

Today, while the civilian manufacture, sale and possession of post-1986 select-fire Uzi and its variants is prohibited in the United States, it is still legal to sell templates, tooling and manuals to complete such conversion. These items are typically marketed as being "post-sample" materials for use by federal firearm licensees for manufacturing/distributing select-fire variants of the Uzi to law enforcement, military and overseas customers.[37]

The Mini Uzi carbine is similar in appearance to the Mini Uzi machine pistol. The Mini Uzi carbine is fitted with a 500-millimetre (20 in) barrel, to meet the minimum rifle overall length requirement for civilian sales in the United States. It fires from a closed-bolt position in semi-automatic mode only.[28]

The Uzi pistol is a semi-automatic, closed bolt, and blowback-operated pistol variant. Its muzzle velocity is 345 m/s. It is a Micro Uzi with no shoulder stock or full-automatic firing capability. The intended users of the pistol are various security agencies in need of a high-capacity semi-automatic pistol, or civilian shooters who want a gun with those qualities and the familiarity of the Uzi style. It was introduced in 1984 and produced until 1993.[21]

The Uzi Pro pistol is a current version of the Uzi pistol. It has rails on the top and bottom, and there is an optional stabilizing brace. Unlike any other Uzi variant, the Uzi Pro pistol has a side charging handle, rather than a top charging handle, and has a three-stage safety. There are three safeties on the Uzi Pro pistol: a thumb safety, a grip safety, and a firing pin block. This model was intended for law enforcement and civilian use, due to the compact size, rails, and a semi-automatic rate of fire. Unlike other Uzi variants, the Uzi Pro pistol is only chambered for 9×19 Parabellum.

The Arma Grupa Strojnica ERO (Arms Group "ERO machine-gun") was a Croatian Uzi clone made locally by Arma Grupa of Zagreb during the Yugoslav War. It was made entirely from steel stampings, causing it to weigh more (3.73 kg (8.2 lb)).[38] The only difference from the Uzi is the selector switch, which is marked "R" (Rafalno {"burst"}, for full automatic fire), "P" (Pojedinačno, for single shot) and "Z" (Zaključan {locked}, for safe) and its rate of fire is 650 rounds per minute. It uses the 32-round magazine as standard, but can use any 9mm Uzi-interface magazine of 25 rounds or larger.

The Strojnica Mini ERO is a clone of the Micro Uzi; it differs in that it had a heavy-gauge folding wire stock like the Skorpion Machine Pistol. It weighs 2.2 kilograms (4.9 lb) unloaded and is 545.5 millimetres (21.48 in) overall with the folding stock extended and 250 millimetres (9.8 in) with the stock folded. It uses the 20-round Mini Uzi magazine.

The EROs were used by the Croatians as early as 1992.[39]

The BA93 and BA94 are Burma-made clones of the Uzi. Production started in Myanmar after 1991 when an Israeli delegation visited the country and supplied the Tatmadaw with Uzis.[40][41] It also included the rights to manufacture the Uzi under license.[42]

The BA93 is based on the Uzi, but with a longer barrel and fixed stock.[43] It was introduced in 1993.[42] It is commonly seen with Myanma soldiers and special forces units operating in commando or VIP protection operations.[42]

The BA94 was introduced in 1994.[44] Improvements made include moving the charging handle from the top to the left with a shorter barrel.[42] This model is mostly seen with Myanma police forces.[42]

As of 2018, both weapons were renamed MA-13.[43]

Norinco of China manufactures an unlicensed copy of the Uzi Model B that is sold as the M320. Early versions were marked "POLICE Model" in English. Modifications were made to avoid the US Assault Weapon Import Ban: the folding stock was replaced with a wooden thumbhole stock, the barrel nut was welded in place, and the bayonet lug was removed.[45] The gun had a gray parkerized finish, a 410 millimetres (16 in) carbine-length barrel and is 800 millimetres (31 in) overall.

The TK-K12 is a Vietnamese clone of the IMI Micro Uzi since 2013.[46]

The Zastava M97 is a Serbian clone of the Mini Uzi.[47] Two variants consist of the M97 with an 8 in (200 mm) barrel and the M97K with a 6.5 in (170 mm) barrel and no folding stock with a vertical foregrip permanent attached.[47][48]

From 1993 to 1996, HAMAS created a total of 350 clones of the Uzi until its production was dismantled by the Palestinian Security Services' Intelligence unit under Moussa Arafat.[49]

A very common question regarding UZI conversions is, “Who did the best conversion?”. That is a hard question to answer as these guns were converted before 1986 and who knows what was done to the gun after it left the original manufacturer’s hands. I use the term manufacturer because some UZI’s weren’t converted by a C2 but by individuals on a Form1. Billistics stands out as one company that did the most complete factory correct conversions. Buyer beware though, when Billistics went out of business there were a number of guns including UZI’s that were registered by them but were converted by others. I personally almost bought such an UZI because the seller boasted it was a Billistics gun but upon inspection it only had the rail removed and NOTHING else was brought to SMG specification. So the best thing is to know what to look for. Hopefully, the information here will advise you on what to look for and you can decide what is important to you.

The 3 different UZI “versions”

The full size UZI which came as the Model A and Model B The MINI UZI Carbine – which all evidence shows that they did not enter the US until 1987. Note that the SMG version was in the US before 1986 which would all be Pre86 Dealer Samples and NOT transferrable to an individual. The UZI Pistol which came into the US in 1984.

Here are some details that all the SEMI’s share but there are exceptions:

The receivers are marked as SEMI’s. They are all closed bolt. Note that for FA use, the bolts must have the lower “lip” as seen in the picture below. This is true for both OPEN and CLOSED bolt FA operation. The SEMI extractors are different from the SMG extractors. Below you see a SEMI extractor in a semi bolt on the left and a full auto extractor and bolt on the right.

They all use SEMI sears which are smaller. Because of this thay also have a smaller opening in the bottom of the receiver so that the larger SMG sear will not fit. Below is a picture of a NON converted SEMI Model A’s sear and openings in the bottom of the receiver. The openings may look large enough to accomodate an SMG sear but they are not.

Below are some different sears: A – Semi sear B – SMG open bolt sear C – SMG open bolt sear that has been relieved on the sides to accomodate the barrel restrictor ring. D – MINI Carbine Semi sear E – SMG Open bolt sear that has had the right side chopped off for use in a Closed bolt setup for a MINI or MICRO. This one’s right “ear” broke off which is what the grip safety needs to work. This one should not be used.

They all have non-ratcheting topcovers with the legal disclaimer on the top of the slot cover.

Below you can see how one topcover has the ratcheting teeth and the other does not. These are MINI topcovers. I made a big circle showing that the topcovers cocking lugs slot go back the same distance for charging the bolt. This is NOT the case with a SEMI FULL Size UZI topcover. To use a Semi Full Size UZI topcover for FA Open bolt operation, that slot would have to be made longer.

They have barrel restrictor rings which restrict the installation of a factory SMG barrel or SMG bolt — EXCEPTION — the factory SMG barrel for the MICRO is relieved for the ring as the factory MICRO SMG has the ring too. Below are 3 different approaches to dealing with the ring.

1. The one on the left shows an unaltered barrel restrictor ring. In regards to the full size UZI, leaving it alone requires that you must use modified SMG bolts (or a Group bolt as mentioned below) for the SMG Open bolt and modified/cutdown barrels. Note that with the Closed Bolt MINI/MICRO, the ring does NOT obstruct the FACTORY IMI SMG Closed bolt but like the full size it does obstruct the OPEN bolt. 2. The one in the middle shows a ring that has been trimmed down. This provides the advantage of interchangeabilty of SMG bolts and better supporting of the barrel than no ring but limits the owner to using modified/cut down barrels. 3. The one on the right is an example of the ring being milled off completely. This allows for interchangeability of all factory SMG parts and leaving the SEMI feed ramp in allows for excellent feeding of virtually all ammo types.

Mentioning the ring brings about the topic of bolts that work with the ring. Group Industries machined their semi and SMG bolts so that either one would clear the ring for ease of manufacturing rather than doing two different ones. Using a Group bolt, the manufacturer wouldn’t have to worry about messing with the ring or modifying a bolt. Fleming commonly did this.

Below are some pictures of an IMI and Group .45 bolt. Note how the Group bolt is machined to clear the ring. This is the same case with the MINI Group bolts.

You can see in the picture below that Group engraved a “G” on their bolts near the extractor retaining pin.

They all use a 9mm diameter trigger group lug that is welded on the bottom of the receiver. This is to prevent installing an SMG lower on a SEMI receiver. — EXCEPTION — the factory MICRO SMG and UZI Pistol both use a 9mm trigger group lug/pin.

Picture below shows a bushing that has been installed so that a SMG pin/lower can be properly installed. Rewelding this area rather than using a bushing is also an option.

The lowers all have a block welded to the bottom to prevent the selector from moving to the full auto position. The lower on the right was from a Fleming conversion where the block was milled off.

The lowers were marked just “F” and “S” for Fire and Safe. Below is a picture of a lower that had the “A” added as well as the additional notch. Fleming either left it like as seen below or he also changed the “F” to look like an “R”.

The selector bars are notched for safe and semi only. Below is a selector bar that has had the additional full auto notch ground in.

They have trunions that are different from an SMG trunion. Full Size: The trunion is a smaller diameter on the threaded end to prevent insertion of a factory SMG barrel MINI Carbine: The inner dimensions do not restrict installation of a SMG barrel. It is the restrictor ring that stops that. The trunion is different to an SMG in that the bottom of it is not relieved to accept the “feet” of a factory SMG OPEN bolt. Pistol: — EXCEPTION — Trunion is the same as on a factory MICRO. The stocks are identical to the SMG models with the exception of the UZI Pistol having no stock. Another exception would be the POST BAN UZI’s which have fixed stocks. With the exception of the UZI Pistol, they all have bayonet lugs. Note that later versions of the MICRO UZI’s have this bayonet lug which is more like an “accessories” lug. Again the POST BAN UZI’s would be an exception as they have had their lugs removed. They have provisions for mounting a sling with the exception being the UZI Pistol. The factory MICRO has a sling pin in the left front sight “ear”.

So what are the various conversion methods? Below is a general summary of the various methods. Each method has its on implications pertaining to each UZI model. Those implications are detailed further on the webpages for each respective model.

Registered Receiver – Usually the most desireable, due to being the most versatile and capable of being “factory” correct. An exception to this would be that there are some registered receiver full size UZI’s that do not have the bolt blocking rail removed. This would be the least desireable because ATF would frown upon removing the rail at this time. A gun like that should have had the bolt registered not the receiver. Registered Bolt – These are usually slotted OPEN bolts. They are normally a regular SMG OPEN bolt that has been slotted to clear the bolt blocking rail and have been milled to clear the barrel restrictor ring of a semi auto full size UZI receiver. There are unusual permutations of these including ones that were registered closed bolts. Fleming did do some MINI Closed bolt conversions. There are quite a few registered bolts that were cut down for use in a MINI or MICRO/UZI Pistol. Remember that the MINI and MICRO/UZI Pistol never had the bolt blocking rail. Note that you could move the bolt around to the other UZI models with the bolt provided you fabricate special cocking lugs for the respective topcover. Registered Sear – Most of these are Fleming Registered sears that are permanently married to the receiver. Qualified also did some registered sears that are NOT married to any receiver but these are extremely rare. Registered LaFrance MG Conversion Kit – These consisted of a short barrel, slotted bolt and modified lower. These had all of his information engraved on the front of the magwell and such are sometimes referred to as a registered “lower”. There was also a matching serial number on top of the bolt and usually his logo above it. “Possible” registered “kicker” – These were mentioned in an old Sept 1984 issue of “Firepower” magazine. Being that they were around at that time, there is a possibility that there could be some registered.

FULL SIZE UZI The ATF opinion appears to be that you can do just about anything you want to the receiver to bring it up to SMG spec. What they do have a problem with is removing the bolt blocking rail. Here are the direct links to the ATF opinion letters that pertain to this:

ATF Letter 46 ATF Letter 61 Registered Receivers and the Bolt Blocking Rail All SEMI auto Full Size Uzi’s had a bolt blocking rail welded in the receiver as seen below. This prevented the use of inserting a factory open SMG bolt which is not slotted. Most will agree that a Registered Receiver conversion that has had the bolt blocking rail removed is the best to have for a full size UZI conversion. Below is a picture of what the bolt blocking rail looks like in a Semi Auto Model A UZI.

There are some registered receiver full size UZI’s that do not have the bolt blocking rail removed. These guns were converted via a slotted bolt that has no markings. This would be the least desireable because ATF would frown upon removing the rail at this time. A gun like that should have had the bolt registered not the receiver. ATF does not approve of this because they think that is “freeing up another MG” because a slotted UZI bolt is considered a MG which would no longer be used if the rail was removed and a factory bolt used instead.

Barrel Restrictor Ring Already discussed above.

Bolts Quite a few people did registered Bolts but the most common is probably a B&G registered bolt. This is just a factory SMG bolt with a slot milled in the side of it to clear the bolt blocking rail. Below is a picture of a registered B&G bolt.

Also note that there are some registered bolts that are closed bolts but those are very rare and not very desireable since it is a welded on lower lip.

It has been reported that some VERY early Model A’s came into the US that had the lower lip on the bolts. This would allow FA functioning by just modifying the lower. ATF had stopped their importation and only a few of them exist.

Sears Sears were discussed on the main conversion page. In regards to the registered sears, Fleming removed the bolt blocking rail from the receiver and engraved his information on the bottom of the receiver as seen in the picture below. The sear was also crudely engraved with the same info with a vibrating pencil engraver. These sears are permanently married to the receiver and cannot be removed. While this information may not be documented on the current form that the gun is on, it should be.

Qualified did some registered sears that are not married to the receiver but are extremely rare.

Trunion The trunion is a smaller diameter on the threaded end to prevent insertion of a factory SMG barrel

Barrels A. Factory IMI Chrome lined SMG barrel. Note that the SMG barrel has the larger diameter band after the flange. B. SMG barrel that has been turned down to fit in a semi trunion and barrel restrictor ring. C. Chrome lined Bushmaster barrel. Note that this barrel has the secondary band for maximum support. If this barrel was installed in an unmodified semi receiver it would be supported by the ring, rear and front of the trunion. D. The Bottom barrel is chrome lined and possibly an IMI cutdown. Note no secondary band so support would be by the front of the trunion and barrel restrictor ring.

Remarking the Receiver Most conversions were not remarked. Fleming did a “Basic” and “Deluxe” UZI conversion. The Deluxe consisted of remarking the receiver to say “UZI SMG”. A factory IMI UZI should really be marked “SMG UZI”. The Deluxe also had the lower remarked to ARS while the Basic usually was AFS.

Back in the 80′s, UZI parts were harder to come by and more expensive. Today, UZI parts are much cheaper and easier to come by.

Mini UZI The MINI Carbine did not enter the US until 1987 so the options are more limited. The MINI UZI SMG was in the US before ’86 as Dealer Samples so there were some around for C2′s to copy from to make RR’s out of them from chopped down and re-welded full size UZI’s like Vector has done after ’86. In particular, Fleming did some of these. Sears

The Fleming Registered sear MINI are permanently married to the receiver. Fleming was registering regular UZI SMG sears before ’86 then after ’86 removing the bolt blocking rail out of the full size UZI and relieving the trunion on the MINI UZI to accomodate the “feet” of the factory OPEN bolt. ATF stopped him from doing anymore in 1988. So there is a window of 1987 – 1988 when these MINI’s were done. This is the only option to have a fully transferrable MINI that has the relieved trunion and is NOT a re-weld. While there is nothing wrong with most re-welds, this is the closest to possibly get to a factory MINI SMG that is fully transferrable.

Qualified also made some registered sears that were NOT married to any receivers but they are extremely rare. Bolts

Before the Vector MINI’s, the most common of the MINI conversions was the bolt gun. These were made from registered full size UZI bolts. Most of the registered bolts were not cut for the feet as most people didn’t realize that you could make the feet smaller to fit under the trunion without modifying it. Note the feet of the bolt

So what happens when you don’t have the “feet”?

For comparison, this is a picture of a full size UZI with its bolt charged. Notice how much distance there is between the bolt face and the back of the dummy round.

Now here is a MINI UZI with the proper bolt with feet.

UZI’s that don’t have the feet still run fine but there is one problem. To avoid malfunctioning on the first round, the bolt should be forward when inserting a loaded magazine otherwise the bottom of the bolt pushes on the back of the round causing it to tilt up.

This particular photo shows a bolt with no feet in a MINI UZI utilizing a proper SMG sear.

This picture shows a MICRO UZI with a bolt w/ NO feet and a SEMI sear. Note how much the ejector is seen in the picture versus the other pictures.

All the pictures above shows what happens when inserting the mag in a bolt that is charged. This photo shows a round being pushed forward slightly. In this case, the UZI will not jam as the bolt was forward then charged AFTER the mag was inserted. (In this case, it is a MINI UZI w/ a SMG sear. SEMI sear works fine too.)

Trunion / Barrels Unlike the full size UZI, the inner dimensions of the trunion do not restrict installation of a SMG barrel. It is the barrel restrictor ring that stops that. The trunion is different to a SMG in that the bottom of it is not relieved to accept the “feet” of a factory SMG OPEN bolt. Another difference is that the MINI’s trunion is “skeletonized”.

Below are three MINI barrels. The top barrel is a factory MINI Carbine barrel. Note that there is no secondary barrel band so the barrel is supported by the band behind the flange and the tapered end for the barrel restrictor ring.

The middle barrel is a factory IMI MINI SMG barrel that has had the breech end turned down to go in the barrel restrictor ring. Again, unlike the full size UZI, this is the only modification needed to fit in an unmodified MINI CARBINE receiver.

The bottom barrel is an unmodified factory IMI MINI SMG barrel.

More details of the trunion will be depicted below when discussing the Vector MINI conversion.            Vector MINI (Registered Receiver) Fortunately for many of us, Vector has come to the rescue by making more MINI’s available to the transferrable market. These were done by taking some of their transferrable Group Industries receivers and modifying them to MINI spec.

Here are some of the details: The full size IMI or Group receivers were not designed to accept the “feet” of the MINI OPEN bolt.

On some Vector MINI’s holes were left in the receiver for the feet to poke through. This example shows where they did weld over the holes. The vertical circle shows the area that was cut and rewelded.

This is an early Vector MINI where they were trying to copy the rear ribs of an IMI MINI. They had to stop short to not mess with the original manufacturer’s markings. A real IMI only has 1 long rib on the left side rather than two.

Again, this long vertical circle shows approximately where this receiver was re-welded.

This is a Fleming MINI showing the left IMI rear “rib”. Fleming had them engraved this way rather than the factory which is just “MINI UZI”.

Right side of the Vector MINI with two small “ribs”. Also note the use of the Model A style sights. Very early IMI prototype MINI’s had these but most evidence shows that the production MINI’s had the Model B style sights. Vector does offer the Model B style as an upgrade.

IMI MINI’s two right rear “ribs”. Also note the Model B style sights found on basically all production MINI’s.

Here you can see that the “ribs” are indentations like the other ribs. Hard to see in this picture but in person you can see the welds going through the middle of some of the “ribs” on the inside.

Vector trunion. They use the same trunion from the full size UZI. Note the Model A style sights.

IMI MINI trunion. Notice how it is “skeletonized”. Also note the factory correct Model B style sites.

Vector trunion that has been relieved to accept the “feet” of the MINI Open bolt.

Here is a picture of an IMI MINI UZI conversion that a dealer had at the Spring 2004 Knob Creek. I don’t know if it was a registered sear, bolt or what. They weren’t too willing to find that out for me. Note that it has a semi sear so I doubt it was a registered sear but also note that the receiver was opened up to accept a SMG sear. The trunion has been unmodified. The bolt however appears to be a factory MINI bolt. It didn’t look like a full size that was rewelded. Note how the feet have been modified to work with the unmodified trunion.

Micro UZI Many of the UZI Pistol conversions are registered UZI bolts like the MINI. Also like the MINI, the Pistol has no bolt blocking rail. Since the UZI Pistols were in the US around 1984 there were some that were registered receivers. Some of the manufacturers that did do some RR UZI Pistols: Wilson Arms, Fleming and Hard Times Armory. LaFrance did quite a few UZI Pistol conversions for the movie industry. Sears

Fleming has stated that he did do some registered sear UZI Pistols but those appear to be very rare as they rarely show up for sale. Bolts

The MICRO was never offered as a factory OPEN bolt Full Auto. They were all closed bolt. Most of the UZI Pistol conversions however are OPEN bolt. The Closed bolt is said to be unreliable in the MICRO but hey can be made to run. Note that the MINI and MICRO both use the same closed bolt assembly. The only difference being that the MICRO’s bolt has a notch in it to accomodate the topcover’s cocking lug.

For open bolt, the UZI Pistol has the same issue as the SEMI MINI UZI in that the trunion is not relieved to accept the feet of a MINI Open bolt. There have been several approaches to this.

1. Use a bolt with no feet and those issues are addressed on the MINI conversion page.

2. Use a MINI bolt with feet. Some UZI Pistols did have the trunion’s relieved for this.

3. Use a bolt with modified feet to go under the trunion. I have seen a RR UZI Pistol that had a modified MINI bolt in it that had VERY thin feet to go under the trunion.

Barrels Unlike the Full Size and MINI, the Semi and Full size factory barrels are interchangeable. This was probably done since they are both short barrels.

Stock Obviously, the UZI pistol does not have a stock. This is a stock buttplate made by Vector for their MINI UZI’s.

Sling Pin and Bayo/Access Lug The factory MICRO has a sling mount on the left front sight “ear”.