Charlie,
Besides worn sear(s)/hammer(s) it can also be a perfectly fine Parker with the tang screws cranked down so hard the trigger is actually depressing the sear partially when assembled. Happens when people tighten a loose action into a spongy stock.
Also look for a replaced trigger, too tall, that is doing the above.
Take the stock off, clean everything, clean and put no oil on the sears and hammers if they are not worn, put the gun back together with the tang screws tightened to the correct depth (flush with the top and bottom tangs) and use snap caps to see if there is a light trigger pull, after determining which way it doubles as Brian suggested.
p.s. Assembled you should have a little play between the sears and the triggers that is taken up by the very light flat or round double spring. Look for the trigger to be pressing the sear when everything is assembled correctly and the rear screw not overtightened. I've had to take a few thousandths off triggers that the replacement stock had lost too much wood when made.
|