I have an H&R 12gauge topper deluxe slug gun, the one that has the large bull barrel and weighs 20 pounds, for deer hunting here in Maryland, where no rifle hunting is allowed. I have experienced lite primer strikes and misfires, got the course for the topper and watched it, great job. So I have .039 inch firing pin protrusion, which seems too low. I tried stoning the hammer nose to increase the protrusion but there is only so much you can go due to the fact that the link needs to slide out of the hammer when the trigger is released, safety first. So I ordered a firing pin thinking I would get one a hair longer and file to fit. Got one from Gun Parts Inc., not the right one, tip .077 mine is.099, tried calling them, no help. Called Jack First and ordered the correct pin but I haven’t received it yet and was wondering if it is even going to solve my issues. Ken, you said in the course about hammer spurs slowing down the hammer enough to cause misfires, mine came with hammer spur, removable, no sights, meant to have scope.
Question, is the protrusion supposed to be .060 or better or are they counting on inertia of the hammer to push the firing pin the needed distance. Bryce
Wrong part sent happens. Sounds like they might have sent you firing pins for 20ga. They offer no-cost return for refund or replacement. It is just time-consuming.
One option is to re-tip your existing firing pin. It is not very hard, especially so if you have a lathe. I don’t, so I just got inventive with my drill press. –TL
Question Follow Up
I guess the problem is, this seems to be and has been an issue with the H&R’s for some time. Google search turns up many posts, but no repair info. It’s frustrating, re tipping the firing pin may be the only option. It’s seems the only time this gun fires is when then hammer is going fast enough to overcome the firing pin spring and throw the pin into the primer on inertia. Some of the post on the internet talk about the transfer bar being the issue but I don’t see how. If you push the firing pin forward till it’s even with the backside of its hole you still won’t have .060. Bryce
Answer
When the pin is flush with the mouth of the firing pin channel, you got 0.039″? That’s the positive protrusion. What do you get if you push the pin all the way in with a punch? That’s called absolute protrusion.
If you have more absolute protrusion, and still room in the hammer rebound, the hammer strut can be adjusted to have more striking energy. That’s an option besides re-tipping. -TL
Question
This ones the link system and doesn’t have the hammer strut. Flush with the backside of the firing pin hole where the link rests and the hammer strikes. So what I’m saying is without a longer pin you can’t gain protrusion, H&R must be counting on inertia, which is a question, Ken, is this an inertia firing pin gun? Bryce
Answer
Not really an inertia firing pin assembly. Since absolute protrusion is more than the positive the transfer bar assembly can strike the firing pin and throw it forward some. If the protrusion is .039 when the transfer bar is all the way forward pushing the firing pin as far forward as it can it is insufficient. (Don’t use the hammer to push the transfer bar forward as it is limited by the nose of the hammer like you describe, cock the gun and use a punch or something to push the transfer bar/striker forward to get your positive protrusion reading). You can machine/file the receiver so the transfer bar can push the firing pin further forward, then refit the hammer so it will push the transfer bar forward the correct amount. Like you state make sure the transfer bar/striker can retract when the trigger is released and the hammer is in the fire position. Ken
