What's the right was to fix a boxlock's hammer timing. Old Spanish .410, after firing the hammers don't start to retract fast enough and firing pins drag in primers/back of shell. Can't open without a hammer. Firing pin protrusion is right. Primers are recessed slightly. Do I add material to top of cocking levers where they contact fore-end? What's the right way? Peening or tig welding?

Thanks,
Steve

build up the cocking levers with TIG where they contact the hammer. They should be in gentle contact when the hammers are at rest in the fired position.

Thanks, skb!