I have this neat little 410 peninusla lock Cogswell with a nipple problem. I will try to avoid puns if I can.

The nipple threads are worn so that the nipples can be removed with mere hand pressure.

The obvious repair would seem to be thread restoration with a metric tool and replacing the nipples with Italian ones offered by OMPS (the Italisn equivalent of Brownnells) hence the metric thread choice.

Before I rush where angels fear to tread, anyone have any less radical suggestions? A search on the web re nipples, other than the obvious results, turns up very little info about hammer guns and plenty on muzzle loaders.

i would think the only other option is to have the threads area built up with tig welding and recut the threads to match the nipples

I would look at SAE threads first. Sometimes when I have a british screw to make and the BA die will not work I can find a ASE thread that is close enough to work. The action body is hard so a slightly over sized soft piece to steel can often be made to conform. Kind of like a push up die works. Neat trick taught to me by a most excellent smith. Once you harden the new nipple threads should plenty strong. I actually just had to do one on a metric thread and used an SAE die to get the new screw started.

I'd be tempted to try Loctite 'Form-a-Thread' just for grins and giggles. Call it a $20 research project. It could always serve as a negative example.

There's even a cheaper method--teflon tape on the threads! Have seen this on a few muzzleloaders where the threads were worn.

Speaking of muzzleloader nipples, every British ML I have ever measured had 1/4" 28TPI threads. Nipples for Muzzle loaders come over size in many different thread diameters such as .255" x 28 or .260" x 28. You might check but if your nipples are 1/4"x28 then starting with an over sized ML nipple might be just the ticket.

My thoughts exactly, Steve.

SRH

I refreshed an old ML last year to use as a wall hanger/shooter. It came to me with oversized nipple threads. I simply checked the thread diameter with a micrometer and ordered accordingly from Track of the Wolf. The new oversized percussion nipples fit perfectly. Below is a photo of my dog and the gun with a wild pheasant I shot with it this season in Nebraska.


The gun is a 13 gauge Belgium made JABC farm implement.

Steve

The Teflon tape is the trick. My Greener had the same problem. A few turns of Teflon tape and the problem was solved. I would imagine that blue loctite would work also.

A method that was used in the days of make do and mend to tighten threads mainly because threading of parts could be a little hit and miss to say the least.
I have used this but never on a gun but I do not see any reason why it should not be successful.
Wrap some fine Copper Bronze or soft Iron wire in the nipple threads this will take up the lateral play in the thread and make things tight again.

I dunno about tape and wire. I use teflon tape a lot on the farm, but not to tighten loose thread fit. I used to shoot M/L a lot, and I used oversized nipples in original guns before, but I would be reticent to put my faith in thread tape or wire wrap when those babies are right in front of my eyes. I've got more faith in a tight steel to steel fit myself. Not saying either of those methods won't work, just that I prefer the oversized nipples. JMHO.

SRH

Is the gun in question here a muzzle or breech loader. original post just said hammer gun. Many breech loading hammer guns have a part which threads into the breech to secure the firing which might be referred to as a nipple. I was under the impression this was the case on the gun in question. If so the nipple would not be exposed to the actual thrust of firing, except possibly in the case of a ruptured primer.
Are the threads mostly worn in the breech or on the nipple itself? If you still have some decent threads left in the breech someone with a small lathe should be able to make a new nipple rather easily.

If it is a ML new oversized percussion nipples for mine cost only $5-$6 each. A small price to pay for safety. BTW since I planned to actually use the gun I installed stainless steel nipples but they can be purchased in regular steel as well.

Steve

Good question, Miller. I was under the impression it was a M/L. I've never heard the firing pin retainer on a centerfire hammer gun referred to as a nipple.

SRH

Thank you to all who offered advice.

I tried the teflon tape trick and it seems to be holding. It will be tried with primed shells first before progressing to low pressure 2 1/2 shells.

For want of a better term I used the word nipple. And it is a breech loading hammer 410.

Coming to think of it, maybe I could not find any parts because i used the wrong term when searching on the net!

I believe nipple is correct for breechloaders too. Toby Barclay was selling "nipple wrenches" at the Vintagers in September.