Percussion cap lock patent breeches

[Naphtali]

American Hawken-style patent breeches look outwardly different from some patent breeches on some British cap lock sporting rifles. The British rifles have what I visualize as a nipple seat shaped as a vertically elongated arch. While American Hawken-style patent breeches have been used on big bore, predominantly round ball rifles, the British breech has been used on BIG BORE rifles as well as those used by normal human beings.

- Excluding aesthetics, what are the differences between them?

- If one configuration is considered superior, please explain why.

[Bob Roller]

The English style as used on the Alex Henry and others of similar style has an interior designed to minimize the pressure build up on the nipple and that IS a requirement on long range 451's using 90 or more grains of powder and bullets in excess of 500 grains.
The Hawken style is not nearly as sophisticated but the lighter powder charges and lighter projectiles,the round ball doesn't run exterme pressures against the base of the nipple. A 45 caliber round ball might weigh 140 grains which is far from the 500+grains of the long range match rifle.
A 54 caliber round ball is only about 230 grains which is the weight of a pistol bullet for the 45ACP.
I hope this sheds a bit of light on your question.

Bob Roller     

[Naphtali]

. . .
I hope this sheds a bit of light on your question.
Bob Roller     

Mr. Roller:

Many thanks. This is precisely the information I wanted. I am aware of at least one very good maker of built-to-order Hawken-style patent breeches - now in his 80s. Who in USA creates built-to-order patent breeches intended, as you identified, to withstand higher pressures?

[Bob Roller]

I am sorry to say that I know of no one that custom makes bolstered or "patent breech plugs". Rod England may be able to furnish the Alex Henry breech that was once offered by Don Brown but it is unique to the English rifles alone. There are those who are capable but don't want the labor intensive job of machining one out of 8620 unless they are making one for their own use.
Try <rtengland864@aol.com>

Bob Roller

[Ben I. Voss]

Naphtali, try these guys: http://cap-n-ball.com/McC/.  I have no personal experience with them, but it seems like another member ( Roundball ?)posted about them doing some custom breech plug work for him. Good luck!

[D. Taylor Sapergia]

Track of the Wolf, and perhaps RE Davis, and likely a few more vendors sell English style patent breeches in castings.  I've used several but only for round ball barrels - never slug twist barrrels, so I can't say if their design is suitable for what you want.  The castings sold have a reduced chamber, usually in the form of a half round cup, and an angled hole to the base of the nipple seat.  In truth, the design is almost identical to the Hawken cast breeches, except for the obvious outward shape of the bolsters.

[Bob Roller]

A hole directly to the base of the nipple is the big bug in the ice cream dish. These cast breech plugs are always drilled like that and I have an original Hawken/Gemmer hook breech that came from the Gemmer Estate and it is also drilled directly to the base of the nipple. I would not trust this arrangement for any long range muzzle loader. To get this job done right,a lot of experience is needed and the other and safest way is the make drill fixtures to hold the breech during the different operations required. The external configuration of the English style is the better of the two and the whole idea would be better if ALL of them were drilled with the assumption that 100 grains of 3fg and a 550 grain bullet were going to be used all the time. This would pretty well guarantee that loads of 70-80 grains of 3fg and a round ball could be easily managed.
The old English bolsters according to X rays I have seen from an Alex Henry were drilled all the way across and in a precise location to compensate for the angle of the nipple and then the flash hole,about ,085 or #44 drill was
drilled to intercept the cross channel.The #44 hole was then drilled NO DEEPER than needed to assure full length and depth of the nipple threads. The hole on the left side of the plug was threaded,plugged,filed,polished and engraved and the right side was threaded,plugged and a platinum plug swaged in over that plug and polished. This is NOT a blow out plug altho some were vented with a very tiny hole on shotguns.
This meticulous drilling,tapping etc.assures a good and as safe a breech as possible.
For what it's worth,there it is.

Bob Roller

[bgf]

I think I understand what you are saying -- those throughholes from the nipple to the chamber sometime come way too close to the surface.  I don't really see the delay from a 90 turn, and it is much easier to get the holes centered so that there is maximum material to withstand the pressure.  A friend of mine bought an Ohio-type percussion breech with the passage drilled so that there was apparently just about the thickness of foil keeping the pressure in.  Luckily he is a smart guy and caught the problem before using it, and knew to check the replacement thoroughly before accepting it!  Some of these breeches are the scariest things I've seen on the market (I got one that looked like a casting void had been filled) -- hard to believe that someone would sell it, knowing what is at stake.  Many now say "x-rayed", which is good, as long as the person doing the x-raying knows what they are looking for. 

[westbj2]

A couple of additional patent breech thoughts.
I have seen modern cast breeches using the angular flash hole to connect with the nipple that are just plain scary.  The angular hole is usually about 1/8" diam with the "forward" side of the hole only missing the base of the breech threads by about that same 1/8",  or in some cases, less material remaining in that area. 

Bob has described accurately the method the Brits used to drill, plug and finish the cross flash channel.

An additional refinement to deal with the pressures of the large bullet and powder charge is in the arrangement of the nipple itself.  The nipple is actually shaped with a mild 'dome' at the end of the threads.  The nipple is fitted so that the dome at its end bottoms out in a mating dome at the bottom of the nipple seat and at the same time locking up on the normal shoulder above.  Much like the timing and fit of a breech plug and tang.  Also, these nipples have a platinum liner to resist the erosion of breech pressures.  Some shooters contend that as few as 20 shots can 'burn-out' a conventional nipple.
Here is a platinum lined nipple.  I don't know the "how and why" of the rectangular orifice.

[Naphtali]

Were I to have difficulty to have made a left-handed patent breech in the style of Alexander Henry for a 1.25-inch barrel, is there a right-handed production patent breech that meets specifications - that is, satisfactory for the higher pressure loads? My thought is, if need be, to buy that breech to have a machinist scale it and replicate a mirror image.

[Bob Roller]

The slit/rectangular flash orfice could be someone's idea about "Spraying"fire from the cap but that is just my opinion.
The x ray pictures I saw belonged to the late Don Brown and were shown to Ted Girodat,Roger Weir and myself in Canada at an International Competition at Kitchener,Ontario in 1987. Ted Girodat was the Canadian Team Captain that year and Roger and I were the house guests of Ted and his lovely wife,Donna.
Ted is now deceased as is Don Brown,Bucky Malson and Terry Savage who were in attendence as well.

Bob Roller

[westbj2]

" left-handed patent breech in the style of Alexander Henry for a 1.25-inch barrel"

The breech on an original A.H. target-sporting rifle is close to 1 1/8",  but you need something a bit larger and left handed.
This would work for a pattern.
http://www.trackofthewolf.com/Categories/PartDetail.aspx/665/1/PLUG-ENG-20-7
The correct cross-drilling and nipple seat could be incorporated into the left handed copy.  Be prepared for a pricey part!
Notice that the plug above has a conventional style British hook unlike some others shown which are copies of the T/C style hook.....a totally inferior design.

[Naphtali]

If the breech shown in your link functions as Mr. Roller suggests higher pressure Alexander Henry patent breeches do, I think I have missed some or all of the point of his analysis?

" left-handed patent breech in the style of Alexander Henry for a 1.25-inch barrel"

The breech on an original A.H. target-sporting rifle is close to 1 1/8",  but you need something a bit larger and left handed.
This would work for a pattern.
http://www.trackofthewolf.com/Categories/PartDetail.aspx/665/1/PLUG-ENG-20-7
The correct cross-drilling and nipple seat could be incorporated into the left handed copy.  Be prepared for a pricey part!
Notice that the plug above has a conventional style British hook unlike some others shown which are copies of the T/C style hook.....a totally inferior design.

[westbj2]

Look at the breech shown in the link as being able to show you all of the exterior angles, dimensions, shapes, etc.  When it comes time to change the interior configuration that Bob and I have mentioned, that can be done on your new "mirror image" left hand variation.   
Jim

[T*O*F]

I recently purchased one of the 1.25" breechplugs from TOTW.  It does not have the obliquely drilled hole that the smaller ones do.  Evidently, it is too large to get the proper angle for the hole to match up.

As with many older guns, the flash channel is drilled from the offside and then filled with a screwed insert.  Of all plugs offered by TOTW, the 1.25" one is the only one I have seen that comes close to being correct.