How an air rifle works - spring?

[Millomite]

I sold my old BSA mercury to a mate of mine for plinking and rats around the yard. He or I don't really understand how they work.

 

All of a sudden the gun stopped firing. He could cock it and it still had the same resistance but the pellet doesnt make it out of the barrel. He took it to a gunshop who said the spring is snapped as well as the seals are rotten. I accept the seals part as I know they were old.

 

Is there any truth in the spring snapping? I thought that if it still cocks as normal there shouldnt be any issues with the spring

 

Scott

[russ91]

shake it about a bit it normaly clunks around or atleast it did im my friends

[Axe]

In all honesty,if the seals are wrotten and the gun old, for the price of a spring £15-17 its probably worth having it replaced anyay. Of course, the gunsmith will charge for the labour to do this, but at least it will get a good service in doing so.

 

As for a broken spring, they are fitted under tension. I imagine you would notice it though, when cocking the rifle. I'm not familiar with the Mercury but I know on my old springer you can visually see the spring where the cocking arm joins the piston.

[berettaman1]

When the spring breaks on a springer the two halves become one, the one halve like a threadrd bolt winds itself down into the other half... causing a noticable weakness on begining to cock the action, and sometimes the gun will not fire due to the pressure on the piston is not there!!often upon first cocking it , a graunching noise is noticed......