Patent breech in underhammer

[ripshod]

Could someone please tell me if I need a patent breech in a .69 cal barrel for my underhammer.The barrel will be 1.25 inches across the flats?The reason I ask is I talked to a barrel maker about a 10 gauge smoothbore barrel 1.25 inches across the flats and he said I would need a patent breech.thanks in advance.

 

[bob308]

i think i would use one. but then i use one on my .45. it just shoots better.

 

[Richard Brinkman]

Anybody know where to find a patent breech for a 1" barrel? I am planning on building a underhammer with a fast twist barrel and would feel more comfortable with a patent type breech than the usual short breechplug with the nipple screwed into the barrel in front of the breechplug. Thanks Richard

 

[Zonie]

Welcome to the Forum.
I can't say I've seen any true Patent Breeches for sale from the commercial houses.

I guess I should clarify that a bit.

A Real Patent Breech has a small anti-chamber that is perpendicular to the bore of the barrel venting into the bore with a rather small connecting hole.

I know there are several people who can make one of these but they are a custom item.

If we are speaking of a "chambered breech" which has a underbore sized hole that is co-axial with the bore, Track of the Wolf has several breeches with that design but I'm not sure how you could use them on a underhammer gun. They are either 'hooked' breech style or they have a tang.

Most of the underhammer guns I've seen use some sort of co-axial feature to attach the barrel to the receiver.

 

[44-henry]

Any good gunsmith that does lathe work would have little trouble making one for you. I've been working off and on for the past few years on an underhammer rifle and I made a patent breech for the barrel I'll be using in it (A fast twist Green Mountain 50 caliber).

 

[Richard Brinkman]

Thats pretty much what I had in mind, all that I have seen are set up for a hooked breech or solid tang. I'm using a Blue Spruce lock and what I was thinking was to ream the barrel about 1" deep thread then take a 5/8" or 3/4" fine thread hard bolt, drill out a .375" chamber screw into the barrel leaving a 5/8" diameter stub to slide into the lock. The nipple sets about 1/2" in front of the lock so it would screw into the barrel plus the breech plug making for a much stronger breech system I think. This is probably much more like the Manton style breech.
The big problem that I have is there is no one that I know of in my area that can handle this type of work. Did ask a couple of "gunsmiths" and they looked at me like I had just lost my mind, told me they do make Remingtons and Savage don't you know? I just walked off. So for me I'll need to send out to make this thing work. Any thoughts and ideas would be appreciated.
Thanks Richard

 

[roundball]

Richard, Track of the Wolf recommended a Custom Breeching shop to me to have patent breeches made...Dennis McCandless is in Las Cruces, NM...great guy to work with.
http://www.cap-n-ball.com/McC/index.htm

I've sent him three barrels to make / install patent breechplugs...new Rice .58 and .62cal barrels to install new breechplugs in...and a used .45cal GM barrel to change/replace the existing straight breech plug with a Patent Breechplug.

Outstanding quality work in all cases...only took a couple days plus shipping time both ways...so you might at least give him a call.

 

[Richard Brinkman]

Thanks roundball I'll give him a call.

 

[Metalshaper]

In my experience :idunno: with a drill press and just a handful of tools you can make your own 'chambered' breech. But then again, I work by the T.L.A.R. Method ( That Looks About Right :thumbsup: )

On mine I set the barrel up on the gun. Making sure the barrel and breech were index marked, so I could return them to the same position..I Located and then drilled the position for the nipple using a smaller "pilot" bit. measuring and drilling so the bit came in to just about center of the BP diameter..

took the barrel off and un-breached the gun. using dykem ( or a black dry erase marker ) and I colored the face of the plug.

Using my centering tool and a scribe.. I marked two crossing lines on the face of the plug ( or bolt in my case) with the plug held in a vise I used my center punch to put a locating 'pip' at this intersection..

with the drill press OFF and UN-Plugged :wink: I used a smaller bit, for a pilot hole and chucked it up.. I Set the breech plug up in my DP vise and using the square, against the bit and the BP I got everything as square as I could to each other.

then I moved the vise so the BP was under the bit and made sure the pilot drill would seat into the the lil Pip I had made on the face ( see above)

once I everything was set.. vise locked into position,plug held tight and square to the bit/quill.. I plugged the drill back in and started it up.. now using just a light feed and some cutting oil I let the bit pick up the pip and get itself started.. then it was just a matter of drilling to the depth of the intersecting hole ( you had previously drilled for the nipple )

once I had reached the depth I wanted?? I swapped to a larger bit and drilled the plug again.. to create the final chamber size.. then I took a countersink reamer.. and with a piece of manilla folder between it and the plug,, I cut a slight chamfer to the face of the plug.. making sure it still had enough diameter to seat/seal against the breech..

after that, it was clean everything out.. re-install the plug in the barrel and finish drilling and tapping for the plug!! Voila' a chambered breech.. or my attempt at them :grin:

Kinda long winded.. easier to do than write about.
I'm certainly no expert < and some opinions may differ on the work?> but that is how I have done mine..

Respect Always
Metalshaper/Jonathan

one caveat..make sure you breech chamber is shallow enough,, that when using a reduced charge, you're not creating a mini "short start" situation!!!

 

[AZ Muzzle]

Contact Fire & Iron at:

[email protected]
Mark Kisenwether
10958 CR 738-H
Webster, FL 33597
352.303.4200

He can do the work or walk you through the process. A really good guy who is an underhammer master.

 

[Richard Brinkman]

Metalshaper I'm real familiar with the T.L.A.R. method been using it all my life but I really like your way of doing it. My only problem now is the barrel is only drilled and tapped about 9/16" deep I need about another 1/2" thinking about buying a drill and tap and take'r deeper by using a hand held drill, then run a bottom tap in as far as possible. What the heck barrel is too long anyway if I really screw it up bad I'll hacksaw it off and send it off to a professional.

 

[Metalshaper]

My only problem now is the barrel is only drilled and tapped about 9/16" deep I need about another 1/2" thinking about buying a drill and tap and take'r deeper by using a hand held drill, then run a bottom tap in as far as possible. What the heck barrel is too long anyway

RH,

that is a dicey thing at best! almost guaranteed to buggar the existing threads :redface: ..you "Might" get away with it..but would be a tough way by hand! < not knowing what tools/tooling you have on hand?>

My Bud did one once, where he chucked it in his lathe ( a HUGE Howa 24" swing 8' bed ) centered everything and then just kinda snuck the appropriate sized bottom cutting end-mill in.. He was able to bottom the hole that way.. then cutting the threads was a snap!!

Just a thought :hmm: if you could find< or grind yourself > a piloted bit or reamer.. you might just get it done??

but then again, I always do things in a most unconventional manner :grin:

Respect Always
Metalshaper/Jonathan

 

[Metalshaper]

Randy and RH,

FWIW...any good 'Smith', like the ones you have been given the names of, are worth their pay! Get's your projects done Correctly and in a Reasonable time.. well worth the $$$ spent if it's within the budget!!

Respect Always
Metalshaper/Jonathan

 

[Richard Brinkman]

You are absolutly right what was I thinking, by the time I ran down parts I could mail it out and have it done correctly.
One thing I'm happy with though is I got rid of that Pilgrim thing what a relief :thumbsup:

 

[bioprof]

What is the advantage of having a patented breech? I would think it would just make it harder to clean.

 

[Richard Brinkman]

I agree it is harder to clean but I'm looking for strenght. Planning on shooting 500 grain bullets with 70 grains or more powder. Using a underhammer normally the nipple will screw into the barrel ahead of the breechplug I can see where this could cause some strenght issues and I don't like the idea of a barrel letting loose with my hands and other precious parts in direct line with flying metal. With the added pressures I am wanting to drill and tap so that the nipple will screw through the barrel and into the breechplug giving a lot more metal surrounding this critical area. Hope this is clearer than mud but the best that I can explain. :hmm:

 

[Melton Kidd]

For an underhamer, you would seat the nipple in a thicker piece. (barrel+ breech plug) with a standard breech, you just put the nipple through the barrel.

 

[44-henry]

9/16" should be safe if you have good thread engagement, a lot of makers only breech 1/2" deep. I personally would send the barrel out to one of the names mentioned and have a custom plug turned and properly fitted to your barrel rather than doing the job without the use of a good lathe.

 

[roundball]

As one reference, I've had today’s patent breeches on every caplock and Flintlock I've ever owned...both production and custom muzzleloaders...no interest in owning a muzzleloader without one.

Patent breeches used today are usually a cross between a true Nock's Patent Breech and a so called chambered breech. Regardless of what one wishes to call them, today’s patent breeches normally don't have the horizontal ante-chamber distinctive to the original Nock's Patent Breech design.

There are vertical step down powder chambers and with the top one being smaller in diameter than the bore diameter, the cleaning jag stops on top of it and fouling does not get pushed down into the powder chambers or fire channel coming in from the vent...so there's nothing to worry about cleaning there while shooting.

The bottom of the step down powder chamber intersects with the fire channel coming in from the vent, and there's nothing below the fire channel to catch / build up fouling even if any could get down there in the first place...don't own a vent pick.

The back blast exhaust from each shot apparently blows down and out the tapered step down chambers and fire channel through the vent and sort of self cleans that area with each shot...ie: I run entire 50 shot range sessions without having to clean down there.

Then normal bore cleaning after use cleans the whole breech area business as usual...either through sloshing solution around and then forcing it out through the vent, or pump-flushing solution in and out of the vent from a pail or using a flush tube approach, etc.

 

[ripshod]

My concern was the screwing of the nipple into the somewhat thin barrel.On my original post I mentioned a 1.25 diameter .69 cal barrel.The barrel is actually 1.125 across the flats.Doing the math that leaves only .217 barrel thickness to anchor the nipple.This seems to be way to thin to me.