Muzzloader - Breach Plug installation

[ilcop22]

'Evening,

I'm currently in the process of building a Kentucky Longrifle from a Track of the Wolf Kit. I have some questions regarding installing the breach plug.

The book I am using as reference to build my kit is "The Modern Kentucky Rifle" by RH McCrory. McCrory describes how to drill and tap the breach on the barrel, as well as how to weld together a breach plug. I have a pre-tapped Green Mountain 42", 7/8" octagon barrel, 5/8-18th threads. I have a standard breach plug to match.

On the ToW website, they offer lengthy, detailed instructions on how to fit the plug, including tapping the barrel, cutting the breach to match the plug, as well as modifying the breach plug. (Seen here: http://www.trackofthewolf.com/Printe...artId=LABOR-BP)

I've already mucked up once messing with the breach plug fit, and have galled 1/2 of one thread on the plug and took a small bit off the thread inside the bore. I didn't properly see to it to avoid seizing. I don't have any issues placing/removing the plug since I've been using proper anti-seize.

To my questions.

1. Is the amount of attention outlined on the ToW website required? I don't want to cut corners and end up blowing my face off if I do this wrong.

2. How much force should I need to apply to the plug in order to ensure proper fit? Moderate force lines it up with the top flat on the barrel, extra force the next, and extreme force mostly lines up with the side flat. This, of course, without having modified the barrel or the plug.

3. The book mentions a potential need to test fire the gun post-build from a distance. Is that necessary when using a modern barrel?

I'm quite green on this build, as the oldest firearms I've built or restored are from WWI. Any wisdom will be greatly appreciated. Thank you.

[ilcop22]

Upon researching further, it seems I must match the plug length to the thread length inside the barrel. Understanding that, my only concern now is the minor galling done to the threads. Does this pose a significant safety risk? Also, is test firing necessary? Thanks.

[Mk42gunner]

Test firing would be very cheap insurance.

Robert

[ilcop22]

After much annoyance, I'm just gonna send it to ToW and have them do it. I don't have the necessary taps to do it right.

[nicholst55]

I took the easy way out on my Edward Marshall rifle, and had Track install the breech plug, front and rear sight, and the staples for the barrel retaining keys. Money well spent, IMHO.

[John Taylor]

Just got done putting in a breach plug yesterday for a customer. Done correctly the plug should seat on the inside as well as the rear of the barrel. This insures a good seal and the threads should never get any powder fouling to cause rust. Always use a lube on the threads when installing to prevent galling. Most muzzle loading barrels are not hard so a plug can be forced to the next flat with a good fitting wrench and barrel vice. As for tightness, it's a feel thing. You could go hand tight then use a wrench to take it to the next flat, after it has a good fit one both areas. I use red layout die to check contact and make adjustments while the barrel is still in the lathe.. The last one had to have the threads cut with single point cutter as I did not have a tap with the right thread pitch.

[Woodnbow]

Just got done putting in a breach plug yesterday for a customer. Done correctly the plug should seat on the inside as well as the rear of the barrel. This insures a good seal and the threads should never get any powder fouling to cause rust. Always use a lube on the threads when installing to prevent galling. Most muzzle loading barrels are not hard so a plug can be forced to the next flat with a good fitting wrench and barrel vice. As for tightness, it's a feel thing. You could go hand tight then use a wrench to take it to the next flat, after it has a good fit one both areas. I use red layout die to check contact and make adjustments while the barrel is still in the lathe.. The last one had to have the threads cut with single point cutter as I did not have a tap with the right thread pitch.

I think the best tip for me is probably to let an expert do the installation...

[FLINTNFIRE]

It is easy enough done , did you get any permatex prussian blue fitting compound , you can check your fitment with it pretty easy , I have breached my own when doing a track of the wolf kit , or others . Have a couple of smaller caliber barrels breached that I have not took the time to go back and finish . There are other books on doing it , I think I picked up 4 or 5 of them and read them through a few times while I had down time . John Taylor is right on seating it as he does .

[KCSO]

You want at least as much thread as the diameter of the plug. Polish the face of the plug to a mirror shine to aid in later cleaning. Plug should fit at the bottom of the recess and the barrel end. A good set of dial callipers will help here and use spotting compound. the bottom of the recess is the most important, you want 100% contact there. If the threads are tapered clean them up with a bottom tap. You want the plug to screw in with only moderate pressure until it comes snug.

[waksupi]

They don't need to be real tight. I used to really gorilla them in, but found it wasn't necessary. Where's it going to go?

[reivertom]

It doesn't take as much torque as people think, the old originals didn't have the metal or tolerances we have and they lasted for 150 to 250 years. Many old guns barely had 1/2" of course threads holding the plug in. Today the main goal is to have no threads or gap inside the barrel where the two meet so corrosion doesn't have a place to take hold, and have the plug clocked to a flat on the barrel. If you haven't cut any dovetails and the bore is centered, it won't matter which barrel flat you have on top. Polish the face of the plug to help in keeping it clean in the future, and some people even concave them a bit before polishing them. It will help in the future if you add some "never seize" to the treads. If you tighten the plug firmly (not until you see stars) and have everything lined up, it is just fine. If you still aren't comfortable doing it after all you learn, get a ML gunsmith to do it for you.

[KCSO]

In the old days when I was taught to do it any flat would not due as all the hand cut barrels were at least a little off center. We set them to shoot up hill so to speak. I still check the bores and try and mark a flat to set the tang to but with a lot of them now it isn't strictly necessary.