Renato Gamba Auto CX707s

[Alex1Nat2]

Hi guys,

A friend has given his auto as it keeps failing to cycle cartridges.

I have a Beretta 303 so understand the basis principle of how autos work however a couple of things jump out straight away.

I've removed the forend & this gun has a 'washer'on the end of the magazine tube which is badly perished & bits crumble when you touch it. See pic.

What does it do & can I get a new one?

At the side of the magazine loading port there is a 'pin'.

Friend tells me when you shoot the gun, the pin will drop out after a number of shots & you then can't load extra carts as the trap door sticks.

What is the pin for?

My 303 has one on the side which allows me to drop the trigger mech out.

Thanks in advance.

Steve

[Gordon R]

No photos - so a bit hard to help.

[TONY R]

Never seen but heard the name of renarto gamba, not sure if gas recoil long recoil or what it is re action type.

But where the ramp hinges there is on many semi autos a holow roll pin that the fulcrum of the ramp pivots on, the trigger group securing pins pass through the holow pin in some cases, some times these roll pins are friction fit from one side like Baikal MP153 for an example sometimes g pinned in place like remingtons etc.

Yours could be a pin that is the wrong size or the holow pin could be missing or a bodged repair with in inapropriate pin or bush causing the trigger retaining pin to be alowed to move when its working, it moves and the ramp locks up it out of allignment.

Take the trigger group out im guessing you will notice the pin adjacent to the weyward retaining pin is different to original incorect .

[Alex1Nat2]

Hi guys,
following my original post i've manged to fully strip the auto, clean what looks like 20 years of 'crud' from the mechanism/trigger etc & took it for
a test run today.
Able to load one into the barrel & 1 into the mag via the bottom port.
Good news - gun goes bang & breaks clays.
Bad news - gun doesn't cycle.
The bolt starts to slide back but doesn't go all the way back (half way-ish) so the empty isn't ejected so the next live cartridge cant load.
Its as if there is not enough gas to force the sliding bolt back.
(I've checked the 4 gas port holes in the barrel & they are all clean)
I'm just wondering if the perished 'washer thing' I have is actually a seal that due to its condition, allows the gas to vent forwards instead of backwards
cycling the mechanism.
When unloaded I can move the sliding bolt back & forth as normal - resistance from the spring within the stock seems good with similar tensions

to my Beretta 303.

Any ideas would be greatly appreciated.

Steve

I would attach a copy of the washer but not sure how too.

[HDAV]

I have a feeling these were a generic Italian semi sold in various names.

 

Some older semi won't cycle less than 32g loads or shorter carts what carts are you using are they 70mm?

Edited December 29, 2016 by HDAV

[Gordon R]

The Gamba CX707 was only sold as a Gamba - gas auto. Get an "O" ring and replace the washer. You have nothing to lose and it will probably solve your problem.

[HDAV]

The Gamba CX707 was only sold as a Gamba - gas auto. Get an "O" ring and replace the washer. You have nothing to lose and it will probably solve your problem.

Was there another gamba auto Gordon ?

[Gordon R]

Only ever seen the CX707 - sold by Budget Guns and Tackle - early 1980s.