Function of a patented breech?

Flint62Smoothie said:

Simple! A patent breech uses a'sub-caliber' bore through the breech plug.

• Place a long ramrod down the barrel that has a bore-sized jag on it
• Place blue tape or other on the rod when the jag seats against the breech face
• Remove rod
• Lay along-side the barrel and place the tape in the same position where it was before, just meeting the mouth of the muzzle
• Look at the breech-end of the rod in relation to the center of the drum or the clean out screw
• Assess against the picture ...

Use a smaller caliber brush or other accessory to clean out a patent breech.

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This illustration shows a "hook breech". They also include the "patent" breech as part of the design. There were many guns made with the patent feature that didn't include the hook feature. It's a minor detail, I know. I've heard also that drum and nipple type systems are, or were, not allowed because they are thought to be weaker and prone to blowing out. Some builders won't install vent liners for the same reason. I'm a little skeptical about that myself. There are people here who have looked at thousands more old guns than I have. Have any of you seen blown out drums or vents?

I may be wrong but on a plain drum the flash of the nipple goes into the drum and then has to make a 90 degree bend into the barrel. I thought that a patented breech had a straight line from the nipple to the bore- hence more reliable ignition.

The Crisco Kid said:

I've heard also that drum and nipple type systems are, or were, not allowed because they are thought to be weaker and prone to blowing out.

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I think some of that blow out theory may have arisen due to drums not being supported by the lock cutout. A continuous hammering could lead to fracturing the drum and a subsequent blowing off of the drum at the fracture line.

Here's a brand new never used drum and plug (along with the barrel) from a CVA 45 caliber Kentucky rifle kit that was never completely assembled. The channel in the breech plug measures just a bare few thousandths under 1/4 ". The pictures I've seen of Pedersoli channels look much smaller.

Red Owl,only on some guns, CVA and Traditions use a drum and have a patent breech and do make a 90° turn. The T/C is also a patent breech and makes an approximate 45° turn.

vibraphonusrex said:

I’ve searched and can’t find a definitive answer to my question. I have a pretty new Pedersoli Kentucky percussion rifle, in .45 caliber. Does this have a patent breech? I, too, will sometimes have misfires after some shooting, and I have been swabbing after several shots, if not after each shot.

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The Pedersoli Kentucky Rifles do not have a patent breech. They have a chambered breech. The term patent breech has been applied to the breech plugs designed with a sub bore diameter chamber for modern manufacturing ease.

The Pedersoli chamber is considerably smaller than bore diameter. This allows fouling to build up at the intersection of the chamber to the barrel. Eventually the fouling will bridge over and block the path of the ignition fron the cap to the powder.

There is a good thread on the forum that gets deep into the details of chambered breeches and Manton's patent breech. Do a search on the forum for Pedersoli percussion breech and at the similar thread posted below.

Buckskinquin said:

Patent breeches are also referred to as an ante chamber. Not knowing you have one can be very frustrating. As fouling builds up in the chamber and drum, you will begin to have misfires. If you have a screw on the end of your drum, you can run a stiff wire or small drill through it to reach the chamber. To clean this ante chamber, you either have to flush it with hot water and soap, or use a 22 caliber bore brush. Field cleaning, use the drill and brush, at home, flushing with water. Get an endoscope and use it. Can’t tell you how many people I have met that didn’t realize their gun had one. It’s also frustrating that the gun manufacturers don’t explain its function and cleaning requirements. Here’s a picture of my Hatfield 50 cal. patent breech. Pedersoli bought Hatfield and for years built many of the components for their rifles.

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Thank you. I had no idea the rifle I bought had a patent breech, and at the time, didn’t even know they existed! I emailed Pedersoli. They didn’t know the term, but sent back a technical drawing, and sure enough, my Kentucky rifle has a patent breech. I’ll adjust my shooting and cleaning regimens accordingly.

While I've never had a problem I knew for a fact was caused by a "patent breech" I have found them to be more time consuming to clean. I do not like them and will not buy another. I've often said the same thing about them that Steve Martin posted. I've owned a few over the decades and have only one that I kept, a .54 US M1841 from Euroarms. The only reason I kept and still have this fine rifle is the amazing quality, accuracy and attention to detail. But I hate any type of "patent breech".

Grenadier1758 said:

The Pedersoli Kentucky Rifles do not have a patent breech. They have a chambered breech. The term patent breech has been applied to the breech plugs designed with a sub bore diameter chamber for modern manufacturing ease.

The Pedersoli chamber is considerably smaller than bore diameter. This allows fouling to build up at the intersection of the chamber to the barrel. Eventually the fouling will bridge over and block the path of the ignition fron the cap to the powder.

There is a good thread on the forum that gets deep into the details of chambered breeches and Manton's patent breech. Do a search on the forum for Pedersoli percussion breech and at the similar thread posted below.

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I met a person who was a Pedersoli dealer. He’s the person that used the term ante chamber. My rifle (50 cal Hatfield) drum was completely fouled with BP crud, had to remove it clear it. In theory its great, in practicality, its awful.

Haveing made numbers of 12 bore flint guns using the Nocks plan. I don't recall the customers whittling on about ignition problems & ones I used despite the comparitivly big internal anti chambers .
I have no experience with factory made guns to any extent or ones that claimed to be patent breached. I used the Left hand style per the earlier depicted drawing (Sans rear screw through the hutt.) I think Nock was a Lock maker died 1805 I think .So to patent his breach in 1757 seems early though he was engaged by ordnance to do design & developement work our Henry was a clever fellow no doubting that . The the basic idea was on igniteing the anti chamber the gases where forced to blast through into the main charge thus giveing off its gas faster enableing the use of shorter barrels and less lead on moving game. I never timed it but seemed to work . .
Rudyard

We've gotten a little sloppy with our use of the term Patent Breech. Nock developed and patented a breech designed to keep the breech area clear of fouling by blasting a jet of ignition gases from the small powder chamber. Manton developed his own similar version of the Nock Patent Breech. Zonie's description in the following thread tries to highlight the differences between the patent breech and the other breech designs. the description of the Pedersoli's breech as an antechamber or a chambered breech is a more correct description of the Pedersoli or CVA/Traditions breech construction. Those designs may well be patented, but in my use of the term only breeches of the design developed by Nock will be called a patent breech.

https://www.muzzleloadingforum.com/threads/pedersoli-patent-breech-design.131405/#post-1826522
Zonie's drawing of several breech designs.

Old Hawkeye said:

Sometimes swabbing after each shot can be the cause of the patent breech becoming fouled & creating ignition failure. You are pushing all the crud down into the breech with a wet patch, then putting powder on top of it. Just food for thought.

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Put the powder in first.

Rudall said:

Put the powder in first.

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After you put the powder in doesn't a properly lubed patch around a round lead ball do the same thing? Why the extra step of swabbing with a wet patch?

When using the patched ball as the wiping agent, the patch must be pretty wet. This often does not dampen the powder enough to be unsatisfactory when shooting in woods walks or shooting at large targets.

When wiping between shots one must know their rifle and how to prevent the fouling build up at the breech that prevents firing. The jag is slightly undersized for the bore so the damp patch rides over the fouling, but large enough for the damp patch to bunch up and pull the fouling out. Better on target accuracy is often observed when the fouling is removed from the bore.

Old Hawkeye said:

After you put the powder in doesn't a properly lubed patch around a round lead ball do the same thing? Why the extra step of swabbing with a wet patch?

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Swabbing between shots is necessary for maximum possible accuracy. The bore condition needs to be the same from shot to shot. The key is to use a slightly damp patch, not a wet patch. Use a loose patch and jag combo that goes down easy and bunches up tighter on the return stroke.

Some shooters believe that damp swabbing is necessary from a safety standpoint. They are wrong. It is quite interesting to watch the comedy of errors that results in a club shoot with shooters wet swabbing patent breech guns. Relays are delayed while the co2 dischargers come out.

Pyrodex makes reliability much worse. Pyrodex + patent breech + wet swabbing makes for quite a show. I don't know why anyone would stick with the hobby after experiencing it and believing it is normal.

As previously stated putting a percussion drum in the side of a thin wall barrel, and not supporting it on the lock plate makes for a safety problem. There is a real chance the drum will shoot off and possibly injure someone.

The patent breeches and long ante chambers seem to be there mostly to satisfy lawyers.

Added later, the previous post and I were typing at the same time.

In my Traditions guns the "flash channel" in the patent breach is .180" . I use a bronze brush and cotton mop for a .17 HMR to clean it. Seriously thinking about drilling it out to .250"

Patent breech works very well for large bore guns with large powder charges. It seems rather pointless on 50 caliber and smaller guns.

Grenadier1758 said:

We've gotten a little sloppy with our use of the term Patent Breech. Nock developed and patented a breech designed to keep the breech area clear of fouling by blasting a jet of ignition gases from the small powder chamber. Manton developed his own similar version of the Nock Patent Breech. Zonie's description in the following thread tries to highlight the differences between the patent breech and the other breech designs. the description of the Pedersoli's breech as an antechamber or a chambered breech is a more correct description of the Pedersoli or CVA/Traditions breech construction. Those designs may well be patented, but in my use of the term only breeches of the design developed by Nock will be called a patent breech.

https://www.muzzleloadingforum.com/threads/pedersoli-patent-breech-design.131405/#post-1826522
Zonie's drawing of several breech designs.

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Thank you for this. I had been trying to describe the problem and it was obvious the picture in his head was different than the one in mine....and this shows why.

For those wondering, the off set angled lines dropping off to the right are representing the lands and grooves of the rifling.

billraby said:

Patent breech works very well for large bore guns with large powder charges. It seems rather pointless on 50 caliber and smaller guns.

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I have two CVA training guns that are 45 cal with it.. they are a bother. one I had rechambered. The other doesn't seem to be as persnikerty and I'm leaving it for the next owner when I am done introducing new folks to the sport.

Okay- I don't know anything and now I'm totally confused. I thought on a drum, the flash hole was usually right in front of the breech plug and the breech plug had a flat face- hence the ramrod attachment to scrape the face of the breech plug. THEN I found out some breech plugs had a concave face and needed a special scrap to match and that on some rifles the hole/threading, etc. went into the breech plug so that you had to first remove the drum before you could remove the breech plug. On the "Patent breech- I might be confusing that with the "snail" seen on Hawken type rifles and I thought on those rifles there was maybe more (45 degree versus 90 degree) direct angle to the bore. Thanks for the issues in cleaning up the area.
My percussion guns have a plain drum. Very seldom had any ignition issues and the breech plug face is flat. I thought it was a simple/plain set up but now, maybe not so bad.

There's a function of the patent breech that's being completely overlooked and that's to provide us with a topic for page after page of discussion.