Converting Marushin UZI to Blank Fire?

Post by kilroyjones



I have a Marushin Uzi (SMG 7 80) that is all metal construction. I was wondering if anyone had tried to convert an Uzi to blank firing like the MP-40?

Post by Michalive

Quote :

There is only a theoretical possibility because you can remove the detonator-pin and so you can load a 9mm blank but the UZI chamber can´t withstand the pressure of a 9mm blank.

A little correction! When you remove the detonator-pin, it is impossible to load, fire or eject a 9mm P.A. blank because the shell would be too deep into the chamber. Only the Detonator-pin hold the PFC shell in the correct position to eject.
If you are searching for a cheap and easy way to convert your Paper Cap into a PFC Cap look at my thread here
http://www.mp40modelguns.com/forum2/viewtopic.php?t=165
But it´s very important that you cut smooth the top of the screw otherwise you risk damage of the PFC cart.

Post by Mark

Hi kilroyjones,

It sounds like you have an early Marushin Uzi that was orignally set up to use the "paper" cap type cartridges.

Michalive is absolutely correct, don't try to convert the Marushin Uzi over to anything except for modelgun cartridges

The best that you can do with the Marushin Uzi is to convert it to use the Marushin MP40 cartridges by changing the original paper cap detonator over to the newer Uzi/MP40 cartridges..

That is the only safe method to use when converting the Marushin Uzi to fire "blanks" as the barrel isn't strong enough to handle the pressures that the 9mm blanks would generate.

Post by kilroyjones



Thanks for the information. I bought the Uzi on Ebay an ordered 30 rds of Marushin MP40/Uzi shells from another company.

When the Uzi arrived, Suprise! the new cartridges won't work. Know at least I know why. The idea of modifying the Uzi to work with the new cartridges sounds like the best idea, as I don't want Uzi parts flying in my face. Thanks again....

KJ

Post by Mark

Hi kilroyjones,

The Marushin MP40/Uzi "shells" are actually the right cartridges for your Uzi the problem that you have is the barrel insert (the detonator) is shaped for the earlier cartridges. This part can be easily replaced with the proper "detonator" for the later MP40/Uzi cartridges.

The Marushin Uzi can be very fun to "shoot" if the proper parts are in place.

Post by Mark

Shooting the Marushin Uzi is fun, however, there are some hints to keep it "shooting"

1. Silicone oil: The action parts like the trigger,sear,saftey etc.

2. Grease: The bolt and the insides of the cartridges with light weight grease.

3. Be sure to clean the detonator and chamber after 2 magazines or so..

4. Check for rough edges on the magazine feed lips and file them smooth..

5. Check for smooth bolt movement.

6. Hold the grip safety tightly when firing to ensure that it won't cause problems.

Post by Claymore

Just read your hints on keeping the uzi shooting, i have had problems with mine, not ejecting misfeeding being the main ones. Both those problems have been cured from info on this site but i am still having problems with it firing more than about five rounds at a time.
So i will do what you suggest about the mag lips and also holding the grip safety, i am sure the bolt is moving freely and i now make sure the ejector is always tight (more info fromt the site that i did not know about).

The other thing i tried recently was putting a spent cap in the round as in the X177, this worked great for getting a better blowback on the bolt.

Every time i try one of the suggestions from here the uzi performs better so try de-burring the mag next.

Post by Mark

claymore,

Just remember that modelguns are sensitive to friction.. So, any time you can reduce friction, you increase the efficiency of the blowback and the bolt speed (if the bolt travels slowly back and forth it causes jams and failures to eject etc.)

Post by Commando

kilroyjones wrote:

I have a Marushin Uzi (SMG 7 80) that is all metal construction. I was wondering if anyone had tried to convert an Uzi to blank firing like the MP-40?

To be honest, it is not worth th hassle!! Firstly you need a solid chamber which has been blocked(with small gas exhaust hole), because blanks can't eject themselves they need the gas to be relayed back. for example when using the SA80 on exercise, you need a BFA this is because blanks need the excess gas to eject and not to fire a round. don't use a BFAand the blank stays in the chamber.