Primer piercing and recoil pad

[Seth Mackay-Smith]

Well I finally got a hammer gun (1891 12ga, 28" laminated) and there are a couple of things I'll have to get fixed - but I would like any opinions I can get before it goes to a gunsmith.
1) It has a 13" lop and I need more like 15" or so - it has the original butt plate with the "Parker dog" so does anyone know of a 2" slip-on pad? A new stock is not in the cards for this gun.
2) More importantly, in 3 out of 4 of the first shells I shot (RST lites, 1oz) the primer was pierced. In researching it on the site I see that some see this as not a big deal, but I'm not too excited about gases blowing back toward me and I _think_ that it should be a simple matter of a shorter firing pin. I do see that Cheddite is a favorite whipping-boy but I just think it would be good to not have to worry about it. Are replacement firing pins available, or will new ones need to be turned and heat treated?
All opinions welcome, including those who think it's a waste of time to worry about this.
THanks - Seth

[Bruce Day]

On hammer Parkers, the firing pins are termed plungers. A pierced primer is potentially harmful to the gun because the combustion gases can blow back through the plunger hole in the standing breech and then into the stock head and crack it longitudinally. Although replacement plungers are available , I suggest you remove yours, measure them and publish the length here. Ask others to compare theirs to yours to determine if yours are too long or if something else is amiss.

If yours are too long, although hardened, they can be ground to proper length. I do not know how they could be too long unless these are incorrect replacements.

As to the length of pull issue, there are several makers of slip on pads, Galco, Conn Shotgun, where one can be sourced. With any of them, add extra pads to suit.

[J. A. EARLY]

Originally Posted by Bruce Day

...A pierced primer is potentially harmful to the gun because the combustion gases can blow back through the plunger hole in the standing breech and then into the stock head and crack it longitudinally...

Bruce,

I thought the same thing as I had a cracked stock head on a top lever after firing RSTs and had pierced primers, but someone pointed out to me that on a hammer gun this cannot happen as the plunger is contained outside of the stock head. So even with pierced primers one should be safe. But I would wear shooting glasses, although the plunger fit is quite tight. From then on I did not worry about the poor thickness on the Cheddite primers in RSTs.

[Seth Mackay-Smith]

Originally Posted by Bruce Day

...replacement plungers are available , I suggest you remove yours, measure them and publish the length here. Ask others to compare theirs to yours to determine if yours are too long or if something else is amiss.

If yours are too long, although hardened, they can be ground to proper length. I do not know how they could be too long unless these are incorrect replacements.

With a replaced battery, the calipers work much better. Sometimes I miss verniers. At any rate:

My plungers are .992" OAL. They stand out just over .170" from the breech face with the plungers fully depressed, if that means anything.

What length should they be/do others have? (I'll post on the hammer gun forum as well)

Thanks,
Seth

[edgarspencer]

Cheddite primers are much more easily pierced than any I use in reloading their hulls. At one point I had a half dozen top lever 16s and two were notorious primer piercers. I removed them and had them ground to a very even radius as they were more sharply pointed. Never pierced another. I buy lots of Cheddite NPEs without any fears.

[WHO]

80% of the time, my 20 gauge top lever pierced the RST primers. The primers must be made of a thinner gauge metal. I know others have complained to RST to no avail.

[Seth Mackay-Smith]

Well I don't completely trust internet research, but from what I can gather they use Cheddite primers, who in turn use a little thinner gauge metal. Hammer guns, at least in some cases -including mine- seem to have pins or plungers that protrude further than others. When combined with a plunger that extends at an angle I could easily see that a thinner gauge metal would have a tendency to tear when subjected to the sideways forces from the angled impact in addition to the usual inward ones. I'm hoping to get some numbers from other members on what their plunger measurements are (without getting too personal) so that I have an idea where it would be good to end up for an overall length. The radii on both plungers are very smooth (thanks for the info, though, edgarspencer) so I'm not sure what else I could do.

[Kensal Rise]

Regardless of what you call them, the firing pins of this gun need to be assessed by a competent double gunsmith. There are a few reasons why your gun pierces primers. Length is only one of them. The correct reasoning of the problem and the proper solution needs professional help. It won't cost much, and you can rely on the gun from then on.

And, yes. Cheddite primers are not classic double gun friendly as a rule.

[Seth Mackay-Smith]

Thanks; I remember seeing some smiths suggested that are not too far from me in far northern VA. I'll talk to them for sure but I really like to get other people's thoughts as well because I think that too often it's a problem if you don't have enough information when asking for a fix, no matter how good the gunsmith is. Of course I'll have them look at the springs as well, as I understand they can be an issue.

[Bruce Day]

Originally Posted by John Campbell

Regardless of what you call them, the firing pins of this gun need to be assessed by a competent double gunsmith. There are a few reasons why your gun pierces primers. Length is only one of them. The correct reasoning of the problem and the proper solution needs professional help. It won't cost much, and you can rely on the gun from then on.

And, yes. Cheddite primers are not classic double gun friendly as a rule.

Mr. Rise, can you help our new fellow Seth by checking the length on your plungers so that he can compare them? On an 1891 gun they are most probably from a top action gun. I would help, but I am in SoDak chasing birds.