I have a buddy that has a Benelli Super Black Eagle II that misfires when its cold.

Basically it goes click and no boom.

Is there a fix for this?

Have you completely take apart the bolt and trigger group ,cleaned thoroughly and lubed with a good oil ?

I am completely unfamiliar with Benelli or auto shotguns in general. I personally favor pump guns.

Is the take apart something I (we) can do or is it for a gunsmith?

Is there a mark on the primer?

I've got an SBE II and it's too good, I want to sell all of the target guns I have...

No marks that I know of (not my gun)

According to Benelli's website the action may not be closing completely. I am going to strip the gun down and clean it well and check the mainspring behind the action. I don't think my friend cleans his guns as well as he should.

When i see something that doesn't work "in the cold" I generally think wrong lube or over lubed. Might be worth a look. If the gun goes click the bolt should be all the way forward.

Benellis are very easy to take apart !!! You don't need a gunsmith to do it .

I'd try degreasing it with gun scrubber and lubing it with Breakfree CLP only.