Flint patent breech

[varsity07840]

Having read a number of threads about the pros and cons of patent breeches, I'd appreciate some feedback on my situation.

The .54 cal. barrel has an early version of "Nocks" breech
in that it has a standard flint plug that has been bored out for a powder chamber. I've had fouling problems that didn't allow enough powder to get down against the touch hole(White Lightning liner) which gave me hang fires. Scraping the mouth of the chamber removed hard fouling. I initially though that the powder chamber was to narrow and was going to pull the plug to enlarge it, but before doing that I discovered that while there was a shoulder where the plug faced, I could get a .50 cal bore brush into the chamber. With a chamber that large. I can't figure out why I'm getting hard fouling build up after a few shots. Comments will be appreciated.

Duane

 

[nkbj]

This is just a guess based on something that happened with some civil war type muskets. The preservative oil and excess bullet lube blowing back down into the breech area would form a black rock with the burning black powder that sealed the bottom of the nipple. Made me crazy. The remedy was not having the stuff there to react with. And, strangely enough, some of the fake type substitute powder would always foul it up on the third shot no matter how well it was cleaned.
Maybe you might have an excess of some product down in that area of reduced diameter?

 

[varsity07840]

This is just a guess based on something that happened with some civil war type muskets. The preservative oil and excess bullet lube blowing back down into the breech area would form a black rock with the burning black powder that sealed the bottom of the nipple. Made me crazy. The remedy was not having the stuff there to react with. And, strangely enough, some of the fake type substitute powder would always foul it up on the third shot no matter how well it was cleaned.
Maybe you might have an excess of some product down in that area of reduced diameter?

Well, I'm not using anything that I don't use in my other flint guns, and the first few shots from a clean, alcohol wiped barrel have good ignition. The only time I've had a similar problem was with My Pedersoli Mortimer, but in that case the powder chamber WAS too small and expanding it cured the problem. That's the only other flint gun I have with a patent breech.
I only use black(3F in this case), a wonder wad over the powder and a mink oiled patch and ball.
It's definately a case of not enough powder getting to the touch hole, because when if poke a wire pick in the vent, the powder isn't packed up tight against it. I'm thinking maybe there's a burr of some sort at the chamber mouth catching the fouling.

Duane

 

[MikeChapin]

I have a .58 flinter I built a couple of years ago that has a patent breech. I haven't had a problem of hard fouling. Just the normal stuff that makes the crud ring in the breech. I use a .22 brush wrapped in cleaning patches to scrub it out when I clean. My breech has about a .40-.45 chamber.

What does happen if I don't get the chamber cleaned well enough during normal cleaning is that I get bridging of the powder at the breechplug-barrel interface. This prevents the powder from going into the chamber. I have the the same problem if I have my .50 with a flat breech get crudded up from shooting a lot in one day. The bridging happens right at the crud ring.

When I see this happening I start slapping the barrel when I put the powder in. This breaks up the bridge and allows the powder to go farther down the barrel.

You didn't say what powder granulation you were using but I did find this was more of a problem when using 2F instead of 3F.

 

[varsity07840]

I have a .58 flinter I built a couple of years ago that has a patent breech. I haven't had a problem of hard fouling. Just the normal stuff that makes the crud ring in the breech. I use a .22 brush wrapped in cleaning patches to scrub it out when I clean. My breech has about a .40-.45 chamber.

What does happen if I don't get the chamber cleaned well enough during normal cleaning is that I get bridging of the powder at the breechplug-barrel interface. This prevents the powder from going into the chamber. I have the the same problem if I have my .50 with a flat breech get crudded up from shooting a lot in one day. The bridging happens right at the crud ring.

When I see this happening I start slapping the barrel when I put the powder in. This breaks up the bridge and allows the powder to go farther down the barrel.

You didn't say what powder granulation you were using but I did find this was more of a problem when using 2F instead of 3F.

Mike:

Thanks for the reply. I'm a dedicated slapper. Doesn't help much after a few shots. I do use Goex
3F in this rifle. I'm going to give Swiss a try.

Duane

 

[MikeChapin]

You also might want to try KIK. It burns a little cleaner than GOEX.

 

[paulvallandigham]

You have some kind of oil or some kind of obstruction down in that powder chamber that blocks the small hole going into the flash channel, and preventing even 3Fg powder from getting down into the flash channel, and over to the TH. It may be nothing more than a burr on the hole at the bottom( back?) of the chamber. If you don't enlarge the chamber itself, you should consider enlarging the hole from the chamber to the flash channel, AND enlarging the flash channel by at least one drill bit size. Then polish the heck out of both holes to remove burrs. :thumbsup:

 

[varsity07840]

You have some kind of oil or some kind of obstruction down in that powder chamber that blocks the small hole going into the flash channel, and preventing even 3Fg powder from getting down into the flash channel, and over to the TH. It may be nothing more than a burr on the hole at the bottom( back?) of the chamber. If you don't enlarge the chamber itself, you should consider enlarging the hole from the chamber to the flash channel, AND enlarging the flash channel by at least one drill bit size. Then polish the heck out of both holes to remove burrs. :thumbsup:

Thanks Paul:

This breech set up has the powder chamber( about 1/2" diameter I'm guessing) bored all the way back to where
the line of the touch hole intersects with it. The
5/16" hole for the line is drilled directly into the chamber. I know it's not a stepped affair like some patent breechec because I can hit the ramrod in the chamber with a vent pick. I don't want to pull this breechplug so close to hunting season, but I thing I will, if I don't get some improvement using Swiss. Anyway, that's why you have a back up rifle.

Duane

 

[paulvallandigham]

It sounds like someone has enlarged that powder chamber, after it came from the factory. The chambers are normally .30 cal, or smaller( in the smaller caliber guns). You may have burns at the inside edge of that flash channel, but at least its a short channel to the TH on the side of the barrel.

Clean the gun well by flushing it with alcohol,and then running a dry patch or two down the barrel. Then load and fire it. Only if it doesn't shoot well would I recommend pulling the breechplug. If you have not done it, take the gun to a gunsmith who has, and knows what he is doing. I learned from a gunsmith, by helping him hold my barrel in his vise with one wrench, lying on my side on the floor under the vise, while he turned the breechplug using another wrench above the vise! It was a 2 man job, for sure. He even had to use a pipe as an extension of the wrench handle to get the needed leverage to turn the plug loose. Once it loosened, however, he was able to turn the plug out with just his fingers.

 

[steelerzzz]

Do T/C and Lyman flinters both have patent breeches?

 

[Herb]

You might have read my comments about Swiss powder in the Shooting Accessories forum, where I had a patent breech flint .58 Hawken. I had more trouble with Swiss than Goex, with heavy charges (120 grains of Swiss 1 1/2 or Swiss 2). I finally solved my problem by polishing the powder chamber, which was about 3/8" by 1" if I remember, and radiusing the entrance. Then when I load I bump the rifle butt on the ground to be sure the powder goes full down. And even if I can see the powder through the WL flash hole (enlarged to about .070), I pick the vent. Next, I prime with a TOW priming valve, 3 grains of Goex 4F. Even then it sometimes flashed. A sure cure is to prime the pan (3 grains) and tip that powder INTO the flash hole. Prime again if need be. That cured the failure to fire or hangfires.

 

[paulvallandigham]

Yes.

 

[varsity07840]

You might have read my comments about Swiss powder in the Shooting Accessories forum, where I had a patent breech flint .58 Hawken. I had more trouble with Swiss than Goex, with heavy charges (120 grains of Swiss 1 1/2 or Swiss 2). I finally solved my problem by polishing the powder chamber, which was about 3/8" by 1" if I remember, and radiusing the entrance. Then when I load I bump the rifle butt on the ground to be sure the powder goes full down. And even if I can see the powder through the WL flash hole (enlarged to about .070), I pick the vent. Next, I prime with a TOW priming valve, 3 grains of Goex 4F. Even then it sometimes flashed. A sure cure is to prime the pan (3 grains) and tip that powder INTO the flash hole. Prime again if need be. That cured the failure to fire or hangfires.

Herb:

Did you pull the plug to polish the chamber?

Duane

 

[LaBonte]

The problem with all of the flint patent breeches currently on the market, at least the ones I'm aware of, the internals are built wrong - here's what they should look like - note tha main chamber is not less than bore diameter and the idea behind them is two fold:
1) Ignite the main charge from the center rather than the edge
2) The anti-chamber was designed so one does not have to use a touchhole pick since only a small charge of powder should enter the chamber to ignite first.

When built like the originals they work great - that comment is based on having at one time owned two originals (a Manton & a Purdey) with the proper built breech - I had none of the hassles so often reported by folks with the modern mostly ill designed copies.

 

[varsity07840]

The problem with all of the flint patent breeches currently on the market, at least the ones I'm aware of, the internals are built wrong - here's what they should look like - note tha main chamber is not less than bore diameter and the idea behind them is two fold:
1) Ignite the main charge from the center rather than the edge
2) The anti-chamber was designed so one does not have to use a touchhole pick since only a small charge of powder should enter the chamber to ignite first.

When built like the originals they work great - that comment is based on having at one time owned two originals (a Manton & a Purdey) with the proper built breech - I had none of the hassles so often reported by folks with the modern mostly ill designed copies.

LaBonte:

The breech plug on my rifle although "hooked", is similar to a standard flint plug in that there is no octagonal back section that mates with the barrel. It's just the threaded portion with the hook on the back, rather than a tang. The powder chamber drilled in it is a constant width down to where it meets the liner. It's smaller that the bore size (.54) but wide enough for a 7/16" ramrod to easilly fit inside it. I think I'm going to roll tnhe dice and try yanking it out to see what's going on.

Duane

 

[Herb]

Yes, I unscrewed the plug to polish the chamber. The hole had been drilled in a manner that resulted in some ridges or "steps" in the cylinder. I could have drilled it larger but chose to polish it with a 3/8" piece of ramrod with valve grinding compound on it, after a small Dremel tool polishing wheel went in.