Breech plug fitting

[BigBoreBLR]

Internally, does the breech plugs need to seat on the counterbore face to prevent fouling from rusting out the threads?

Or, don't sweat it and just make it line up ok externally.

 

[coloradoclyde]

This might help, "Track" gives a detailed explanation. http://www.trackofthewolf.com/Categories/PartDetail.aspx/1012/1/LABOR-BP

 

[necchi]

Internally, does the breech plugs need to seat on the counterbore face to prevent fouling from rusting out the threads?[/

Yes.

Or, don't sweat it and just make it line up ok externally.

Bad idea,, it needs to be done correctly.
Good luck, I did one by hand,, never again,, I'll pay to have it done.

 

[don hepler]

Yeah, you need a lathe, or it's going to be a lot of work. TOW instructions, are right on.

Would not be fun with a file.

 

[longcruise]

I have done three and did not find it particularly daunting. Most important ingredient is patience.

Ever good builder instruction manual describes the process completely. Dixon's, etc.

 

[Pete G]

Yeah, you need a lathe, or it's going to be a lot of work. TOW instructions, are right on.

Would not be fun with a file.

If you do not have the patience to do the job with a file and square you do not have the patience to finish building a proper rifle either.

 

[longcruise]

MeThinks you are correct.

 

[necchi]

If you do not have the patience to do the job with a file and square you do not have the patience to finish building a proper rifle either.

:bull:
Myself as example,, I'm not that much of a metal working kind of guy, never have been and don't have the desire to become one.
While there is basic metal working issues with every build, and fitting a breech plug is certainly a way to learn a few skills,, spending hours with files for a breech fitting and/or draw filing a barrel for that matter is not a task I look forward too.
It's not so much a matter of patience so much as a desire not to do it. It's not fun.
My paying Track or another competent service $25 is little for peace of mind.

 

[galamb]

I time my plugs by hand with a file (and a digital caliper and a small machine square) - and yes it's definitely an exercise in patience.

But I also have my barrels "made" for me most of the time so I can specify the breech only being bored .5".

Since most plug journals are a little longer, it's generally just the plug you have to file down (if you aren't fussy about which flat ends up as the bottom flat).

The worst barrels to time were/are Green Mountains - they breech them 5/8" deep so you almost always have to remove some of the barrel metal to time a plug.

Track sells some plugs that have a journal almost exactly the length of the breech on Rice and Colerain barrels - if you stick with them, even if you lack patience you can usually time them in a single evening (if you have done it before).

 

[TMan51]

Yeah, you need a lathe, or it's going to be a lot of work.
Would not be fun with a file.

I recently did my first plug install. I used a belt sander with a 600grit belt, and leveled/squared everything carefully. By rotating the barrel on the flats with a carefully leveled feed tray and the fence squared to the belt, it was fairly simple and easy. Slow is best.

There are people that can create a face from marble with a hammer and chisel. If you are not there, some options in equipment can make a difference. Files are for artists when it comes to plugs. I have nary a single art gene.

 

[BigBoreBLR]

Do you have to get the plug face perfectly square to get a seal? Do you need to check mating surface with some Prussian blue or marker.

I have the dixons book, but the glenville book is coming in soon.

 

[BigBoreBLR]

I love building muzzleloaders.

You're always on the hairy edge of really screwing something up almost every minute......

I work in engineering. It's funny how you need a special tool for this and that. However, these fine arms were made for almost a millennium with fire, hammer, and a file.

 

[don hepler]

I'm a machinist..........that's the way I think. I'm not going to sit at my work bench and file a breech plug, when there's a lathe sitting right behind me. Besides if you buy a breech plug, chances are it was done by machine, and so was the barrel, the lock and the triggers.

On the other hand, draw filing a swamped barrel, is fun. I wonder......who made the file.

 

[galamb]

This is my basic process:

I use a tap to clean out the breech end of the barrel (there is usually a burr or whatever at the bottom) - I use a plug tap for that which doesn't exactly leave a "squared" shoulder - there is a tiny taper - but it is minimal.

I then measure the depth with the caliper.

I run the plug through a die to clean up the threads and try a quick fit (with anti-seize on the plug) to make sure it's not loose etc - want a tight fit or I get another plug (never had to yet).

Clean up the plug and measure the journal, mark it leaving a few thou extra - mark it with a magic marker and then wind it back into the die.

I use the die as a guide and file the plug down to my mark (almost - I leave the mark "just recessed" into the die).

The top of the die leaves me a nice flat surface to file the plug to and it's "hard enough" that the file skips over the die when I get down there.

I then use a magic marker to (paint) the plug face and screw her in until "snug".

Back it out, file anywhere (a couple of swipes) where the marker has been smudged, paint it again and repeat.

I keep doing that until I am about 1/3 of a flat from where I want to "finish".

When I get there using "some hand pressure" to make it snug, I call that good and give it a quick torque to get it lined up where I want it.

I do pull the plugs and if you put a straight edge on them, the face is never "perfectly flat", there is a tiny taper.

That's my system.

If the breech is threaded "deeper" than the plug journal I usually grind it down a bit (bench grinder/jig) before I work on it with the file.

If the barrel needs work, I do that first - shooting for .510" thread depth which gives me a little "wiggle room" should it need some file work to square it up.

So the barrel gets "squared", the breech plug face does "not" (at least not exactly).

Works for me - others may differ...

 

[BigBoreBLR]

What are the popular tap and die sizes for rice and Colerain barrels. Lets say 36 to 54 cal. I doubt I would ever go bigger or smaller.

I need to check my size, but I have a 13/16ths 45 cal Colerain, it was 42 inch before the hacksaw job to 36 inch.

 

[ehoff]

Standard breech plug thread sizes are 9/16-18, 5/8-18 & 3/4-16.

 

[longcruise]

Your Colerain should be tapped 5/8-18.

 

[galamb]

Yes 5/8-18 for 40/45/50 cal, 3/4-16 is relatively standard for 54 cal.

On your side of the border I have seen more than one Ace Hardware shops that has the 5/8-18 taps and dies "on hand".

That's where I got mine - think it was like maybe 20 bucks for the pair.

The 3/4" was a little more illusive. I only needed them once but did source them from an online machine tool place.

If you only think you will install one plug, as has been suggested it can be done for you for 15-25 bucks at a shop (particularly where you source the barrel).

But if you know that this will just be one of many, I would get the tap/die. Even if you can't find a plug tap you can customize a taper or bottom tap.

I ground off the last couple of teeth on mine (after busting the last tooth - common) so the bottom of the tap actually can fit into the bore without touching it while bottoming out in the breech - a couple of touches on the grinder will leave you a "custom" breech tap.

 

[BigBoreBLR]

Thanks,

I removed one small burr from the barrel threads and the plug went in virtually all but one thread by hand.

The plug is .625" and the barrel is .555"

I am down to .570 on the plug, but have .030" gap between the barrel and plug. I don't get a mark on the plug face with it either. Tried the marker, no luck, then used the inlet black, no luck either. Can't find my Prussian blue.

I think either I need to remove a bit of the thread at the end of the plug, or run the right tap down the bore. I ordered a bottoming tap 5/8-18. I got a 3/8npt-18 tap and a 18 tpi thread file to verify the size.

Holding off until I get the right tap. But, I can practice making dovetail with the 6" I cut off the barrel.

 

[Zonie]

I remove roughly the first thread (or a little more) from the breech plug to clear the partial thread that is always present in the barrel at the shoulder.

The thread removal will not significantly weaken the plug and it allows the face of the breech plug to fit tightly against the face at the end of the guns bore.

Removing the thread doesn't take any real talent.

Using a good, sharp flat file just gently file the thread while slowly turning the barrel.
Do not go deeper than the bottom or root of the thread V. You will want to leave as much of the plugs face as possible to seal off the joint.