1911 loss of power?

[Big Mat]

Mat, are you referring to a Umarex 1911 or the Tanfoglio type 1911. As you mentioned the CP88 I guess its the Umarex type ?

Baz

Yes it the Unarex 1911 I believe

[Benelli B76]

Yes it the Unarex 1911 I believe

On these pistols people have a tendency to overtighten the brass B1680 cartridge screw which then causes too much pressure to be put on the Cartridge Lock EC148 which is made of Zinc alloy. This lock tends get a permanent bend causing it to "overcam" when pushing the CO2 cartridge against the seal, so it pushes up and drops back slightly. I have had to straighten quite a few of these using a little heat to get them to hold the capsule neck tight against the seal and not leak CO2. Another cause of loss of power is the soft transfer bar getting distorted by too much use. I remove these completely and make up the striking difference on the hammer by inserting a hard pin in the hammer face.

Baz

[Big Mat]

On these pistols people have a tendency to overtighten the brass B1680 cartridge screw which then causes too much pressure to be put on the Cartridge Lock EC148 which is made of Zinc alloy. This lock tends get a permanent bend causing it to "overcam" when pushing the CO2 cartridge against the seal, so it pushes up and drops back slightly. I have had to straighten quite a few of these using a little heat to get them to hold the capsule neck tight against the seal and not leak CO2. Another cause of loss of power is the soft transfer bar getting distorted by too much use. I remove these completely and make up the striking difference on the hammer by inserting a hard pin in the hammer face.

Baz

I had another try with it on the weekend, C02 cartridge went in fine with no hiss, but upon firing, the power fluctuates hugely between shots, one full power, then a couple barley getting pellet out of the barrel, then half power etc, in a random order. i've no idea what it means, C02 is a new area for me.

[Benelli B76]

I had another try with it on the weekend, C02 cartridge went in fine with no hiss, but upon firing, the power fluctuates hugely between shots, one full power, then a couple barley getting pellet out of the barrel, then half power etc, in a random order. i've no idea what it means, C02 is a new area for me.

Have a look to see if there is a flat piece of metal that moves up between the hammer face and valve pin when the trigger is pulled. This transfer bar gets hammered out of shape and causes problems. On the old pistols I removed them. Not sure if they are in newer pistols. I made up the difference in hammer reach by inserting a hard screw in the hammer face.

Baz