Breech plug/drum disassembly question.

[Clint Meier]

Thank you for the welcome responses to my introduction! Glad to join with you all.

My first question is in regards to a percussion ML rifle that my dad recently gave me. It is stamped “Remington” on both the lock and the barrel. He got it from relatives of a family member who passed away. It looks to be about .40 caliber (haven’t measured it yet), with a very distinctly hexagonal bore which has a very deep groove cut into the each of the corners of the hexagon and looks to be slightly belled at the muzzle, perhaps to facilitate starting a patched ball. It has no drum (or nipple), and appears to be in decent original condition otherwise.

In looking to order a new drum, drum drilling jig and nipples from TOW, I noticed a caution printed on their web page as follows:
NEVER remove a fitted and finished breech plug or powder drum. Removal risks permanent damage. Bore obstructions can more easily be removed using other methods.

I had intended to attempt to remove the breech plug so that I could examine, clean and measure the barrel (or a slug pushed through it), and am wondering why the caution about removing the breech plug. If it unscrews and can be screwed back together, what harm have I done? Your comments would be greatly appreciated. Thanks!

 

[paulvallandigham]

Remington originally made barrels for other gunmakers, and there are lots of " Remington " barrels around made during the first decade of the 19th century, and, of course, much later, after he began making and selling his own guns. Without knowing more about the gun, and seeing pictures, I don't think anything you have told us much to work with. There were hexagonal barrels made, but people quickly discovered how much a PITA it is to inlet a stock to hold such a barrel. There are Octagon Barrels with Hexagonal, or 6 Grooved barrels. That is not uncommon at all. As to the actual shape and size of the lands and grooves, once you get the gun, and can take exact measurements, and pictures, I am sure the members here will be able to help you narrow down where the gun might have been made, and even by whom.

The only problem with removing old Breechplugs is that they are often rusted into the barrel. The iron in those old barrels is softer than our modern steel barrels, so care has to be used in trying to remove the plug. It can be done. But, You might want to find an experienced smith to do that for you. If you need names, let us know.

 

[Zonie]

I think the warning is intended primarily for people who own some of the modern reproductions.

One of the first things people want to do if there is any type of bore obstruction is to remove the breech plug.
On many sidelocks like the newer CVA's and some Traditions the drum is actually threaded into the side of the breech plug and unless it is first unscrewed it is impossible to remove the breech plug.

Some of the other modern repros have their breech plug screwed in so tightly it is almost impossible to remove.

On all of these guns, removing the breech plug will void the warranty.

You asked what harm could come from removing your guns breech plug.

First, the most obvious is that you could severely mar the barrel or the breech plug in your attempt to remove it. Most likely it is rusted in place.

Second, many of these original rifles had very short threaded sections without a lot of threads on them.
If the threads have 'rusted in' and deteriorated, removing the plug will dislodge the rust. In fact if the rust is severe and you remove it a problem will come up.
The problem is the threads will be undersize.
Even if there are enough threads to reassemble the breech pug and safely shoot the gun, the undersize threads will require the plug to be screwed in using more turns to make it tight again. This will cause the plug to not line up with the top flat of the barrel, assuming it is an octagon.
Even if the breech of the barrel is round, the breech plug is what "times" the position of the barrel and if the barrel rotated further than it originally was to get the breech plug tight it now will be rotated in the stock.

If this isn't clear, imagine the plug turning an extra 1/16 of a turn to get it tight.
Now, when the barrel and plug are reinstalled into the stock, the sights will be rotated 1/16 of a turn counter-clockwise from where they used to be.

The chances that the old drum threads are the same as the new drum threads is very remote as the Unified Standard Screw Threads were not used in the mid 1840's. The National Screw Thread Standard wasn't established until 1928 and the Unified Screw Thread wasn't standardized until 1948.
Because of this, if you choose to install a new nipple drum make sure there is enough material to allow you to completely remove the old threads and re-tap with larger threads that are standardized and available on the new drums.

 

[Clint Meier]

Gents, thank you kindly for the information! If I proceed with this at all, I now know more about the hows and whys.

I guess I was not clear earlier, but the barrel is a full octagon barrel with a hex bore. The hole for the drum readily accepts a 3/8"-24 tpi bolt with what I would term a "normal" fit of thread, indicating that a drum with that thread size would tighten up well. When looking into the drum hole, I can see where the drum threads cut into the front face of the breech plug. The threads could already have been enlarged to 3/8”-24 by someone else.

The lock plate has a cut out that will accommodate a drum 1/2" in diameter.

In looking at the breech plug/tang, it appears to have only a threaded plug that goes into the end of the barrel, with the tang attached directly to the rear face of the plug.

There is more info on the barrel, but I will save details on that until I can find some time to take some proper pics of the gun and present you with more details. I really appreciate your help!

Best regards”¦..Clint

 

[Russ T Frizzen]

Are you talking about a full length hexagonal bore such as was used in a Whitworth rifle, or is it just filed to appear this way at the muzzle? Many old rifles have deep rifling that appears to be unusual at the muzzle, but is actually quite normal down bore a bit. I have a rifle that looks like it has a bore shaped almost like an asterisk, but that's just the way the muzzle is filed.