loose nipple

[amm1851]

I picked up a Lyman Deerstalker caplock earlier this year from an online auction site to use for hunting this fall. I have owned these rifles in the past in both flint and cap and like them a lot. I have mostly shot flint the past 15 years or so, so this is a bit of a change for me. I have encountered a problem that is new to me; the nipple works loose from the threads in the bolster (or whatever you call it), while I  am  moving through the woods, and has prevented the gun from firing reliably.  Oddly,  this did not happen during the various times I shot it prior to hunting season. I have checked it and it has the proper threads (Lyman's very odd 6 x .75mm) and seems to seat firmly, yet when I carry it while hunting the darn thing works loose.
I don't want to glue it in, for obvious reasons,  but I want to be able to depend on it next week when I am on vacation hunting.  I believe the nipple is the factory one from Lyman,  as the #11 caps fit very tightly,  a characteristic of Lyman's caplocks. I may try putting some fingernail polish around the base of the nipple or something similar to hold it in.
Any suggestions would be welcome; I may resort to buying replacement hot shot nipples for it. Or I may get lucky,  get some dry weather next week and just take my flinter.

[Ohio Joe]

I can't say that I've ever heard of this happening before, but there's always a first time.

It just works itself out after it's seated while you're carrying it?  Perhaps get your hands on some beeswax and put that on the nipple threads,,, though the finger nail polish should work also.

Was the nipple ever cross threaded at one time I'm a wondering?

[amm1851]

I can't say that I've ever heard of this happening before, but there's always a first time.

It just works itself out after it's seated while you're carrying it?  Perhaps get your hands on some beeswax and put that on the nipple threads,,, though the finger nail polish should work also.

Was the nipple ever cross threaded at one time I'm a wondering?

It's a new one on me, too. I don't know all the history of the rifle, but it had been used very gently before I bought it. In fact, it may never have been shot before.  I was thinking I might try to file some off the bottom of the nipple; maybe it isn't quite seating all the way, although it seems tight. That and the polish should hold it in place, I hope. And I will try to find a replacement nipple.  I have several, but they all seem to be the wrong threads.  

[TallTexan]

Just a suggestion but I've always had good luck using the Treso bronze nipples by AMPCO. These never seize up or become difficult to remove, I assume because they aren't steel. Also, having owned several Lyman rifles I know to immediately replace the factory supplied nipples which are notoriously cheap.

[amm1851]

Thanks for the suggestion.  I will see what I can find locally.

[Hawken]

Get the correct size tap and chase the threads out and install new nipple!