Nipples and drums

[PIKELAKE]

I am not a cap locker but I need help to settle a bet. I say "a nipple's threads should not protrude into the drum just a vent liners threads should not protrude into the barrel". He says, " it does not make a difference as long as you able to clean out the drum". Besides the cleaning issue, I am guessing that ignition would be more consistent if there weren't nipple threads blocking the hole in the drum.  Can any body help on this one?  .......JZ

[Dphariss]

I am not a cap locker but I need help to settle a bet. I say "a nipple's threads should not protrude into the drum just a vent liners threads should not protrude into the barrel". He says, " it does not make a difference as long as you able to clean out the drum". Besides the cleaning issue, I am guessing that ignition would be more consistent if there weren't nipple threads blocking the hole in the drum.  Can any body help on this one?  .......JZ

The best advise I can give is to use a patent breech.
Dan

[Steve-In]

Most drums are about .500 to .625 in diameter.  The nipple threads are about .200 to .250 to the shoulder so they will project into the flash channel of the drum.  I usually make a flat on the drum where the shoulder meets it.  I have clean out screws in all my drums that are 10-32's.  I drill out to the screw with a .201 diameter drill.  I never had an ignition problem with this method.

[Glenn]

Most drums are about .500 to .625 in diameter.  The nipple threads are about .200 to .250 to the shoulder so they will project into the flash channel of the drum.  I usually make a flat on the drum where the shoulder meets it.  I have clean out screws in all my drums that are 10-32's.  I drill out to the screw with a .201 diameter drill.  I never had an ignition problem with this method.

Sounds like good advice.  Thanks for the specs. and ideas.   

[PIKELAKE]

Steve-In, so you are saying that it makes no difference if the nipple protrudes into the drum. I would have thought  different. I'm no cap lock person so I guess I lost the bet. Thanks for taking the time to answer. Now I have to come up with 14 trillion dollars.

[Dphariss]

I would advise annealing the drum completely. Heat to red and either air cool or quench and then anneal.
They are all made of cold rolled, are thus brittle and can and sometimes do, break off as a result.

Dan

[Mike R]

if the drum screw sticks into the bore too far it will interfere with cleaning--cutting patches at the the least or grabbing jags or worms at worst.  The thing should be pulled and filed down more flush with the inside of the bore.

[PIKELAKE]

I am not building a cap lock rifle. My pal and I were just inspecting one. It is not ours. We were noticing that the "nipple threads" extended into the drum. I thought that they should not. The drum is fine. That is all folks. Thanks again....JZ

[Dphariss]

I am not building a cap lock rifle. My pal and I were just inspecting one. It is not ours. We were noticing that the "nipple threads" extended into the drum. I thought that they should not. The drum is fine. That is all folks. Thanks again....JZ

Given the dimensions of the commercially available drums and the length of threads on most nipples there will be threads in the powder passage.
Even better is the rebate that some nipples have so that they only have a few threads and some of these in the powder passage.

Dan

[Acer Saccharum]

Dan, did the drum and nipple come about as a 'conversion' for flint to percussion?

So many drums get turned beyond their original setting. the you see teflon tape, or copper shims taking up the slack. This usually means the threads are stretching. Never a good scenario.

Don't like them drums, no sir, I don't. I've seen several gone missing at the range. Fortunately, no one found them.

[PIKELAKE]

Just want to add one more thingy to my original post. I think Dan is spot on in suggesting a patent breech for a cap lock. I know people go the drum route and it works, but I would personally feel better with a patent breech. Secondly, I think Acer is right about drums getting turned past their timing. I would think that constant removal to clean or whatever would upset the whole works over time. Well,my times up. Thanks gents for more things to ponder...JZ

[Roger Fisher]

Dan, did the drum and nipple come about as a 'conversion' for flint to percussion?

So many drums get turned beyond their original setting. the you see teflon tape, or copper shims taking up the slack. This usually means the threads are stretching. Never a good scenario.

Don't like them drums, no sir, I don't. I've seen several gone missing at the range. Fortunately, no one found them.

Good ol Acer is right of course,  that is why I have so many drums in drawers that didn't line up.

[Dphariss]

Dan, did the drum and nipple come about as a 'conversion' for flint to percussion?

So many drums get turned beyond their original setting. the you see teflon tape, or copper shims taking up the slack. This usually means the threads are stretching. Never a good scenario.

Don't like them drums, no sir, I don't. I've seen several gone missing at the range. Fortunately, no one found them.

Its a cheap way to make a percussion gun.
Either as a conversion or as made.

Dan

[Tom Cooper]

It's the way it was done to bring the flints into the percussion era for a time.

I don't seem to have a problem with them, I have done a couple and they are right as rain.

I don't use the pre-drilled units so there is no timing issues, and I also use an oversized drum turned down on a lathe for precise contact on the cut-out of the lock plate.

YMMV