KSC Macll refusing to fire

[HuntR]

So my friend just gave me his mac11 to have a look at and see if i can fix it. And to be honest i'm totally stock on it. The gun refuses to fire. I can manually cock the bolt and when i press the trigger the bolt dose move forward. When i do this the rounds do chamber however no gas coming from the magazine. Have tried other mags, and they work in another mac11. Am i right in thinking the hammer spring has given up or could it something else. Also when the bolt is forward the nozzle doesn't pretrude into the barrel/hop section. Is this normal. Can get pictures of the nozzle/bolt if it helps

[The Keeper of Secrets]

Re: KSC Macll refusing to fire

Does the bolt completely shut?

The gas hammer is built into the bolt, and hits a bit of metal in the lower reciever, which strikes the magazine's bas valve, releasing gas into the gas engine to blow the gun back and start the cycle again.

Shine a torch into the magwell (without a mag in), cock the gun back and then fire it, do you see the valve knocker protrude to hit the valve?

[HuntR]

Re: KSC Macll refusing to fire

Yep the bolt completely shuts. I can see a little piece popping out yes