Coning the touchhole

[jtmattison]

Is it benificial at all to slightly cone the touchhole? I thought it might speed ignition a bit by directing the flash to the charge.

I'm just a novice flinter here doing some thinking.

Huntin Dawg

 

[papellet]

The touch hole liners on my lymans are coned. they work a lot better than the original installed liners. i bought mine form[url] rmcsports.com[/url].

 

[Big John]

A touchhole liner coned on the inside allows the charge to be closer to the flash in the pan, hence faster ignition.

 

[Slenk]

I cone my touch holes a wee bit on the outside , helps a lot .They are also coned on the inside when I buy them . This one in the photo is stainless steel from Track of the Wolf . May not be P.C. but I don't think anyone is going to stand on my right side real close and sqint at it while I'm shooting . I actualy had a fellow try that once , don't think he will again now ( lost his big red beard )

Slenk

 

[roundball]

Thompson / Centers new vent liners are redesigned to include a huge opening on the outside to funnel the flash effect into the powder charge...so large they use a hex wrench to remove & replace the liner.

There's a bevel / radius all around the very top / outside edge of the hex well to funnel the flame effects down into the well, and there's a bevel down at the bottom of the well to channel the flow directly into the hole.

The hole is very large at .075" (see photo) and you can see kernels of powder sitting right in the hole due to the large cone on the inside...very, very fast vents...apparently self cleaning, never use a vent pick, etc.

 

[frenchymanny]

Roundball,

May I ask you which T/C is your rifle?
I find the fit and finish most excellent!

Regards,
Manny

 

[squirejohn]

Interesting that TC's vent liner is .075. I drilled out vents on two guns to 5/84 (.078) and found that they sometimes lost a considerable amount of powder through the vent when useing 3F. 2F was OK.

 

[Bartek]

Coned touchholes by Prussian muskets in the army of Frederick the Great were one of secrets of his victorys.
:hatsoff:

 

[roundball]

Roundball,

May I ask you which T/C is your rifle?
I find the fit and finish most excellent!

Regards,
Manny

That's a TC Hawken

 

[roundball]

Interesting that TC's vent liner is .075. I drilled out vents on two guns to 5/84 (.078) and found that they sometimes lost a considerable amount of powder through the vent when useing 3F. 2F was OK.

I use Goex 3F in .45/.50/.54 calibers and there's no loss in any of them...you can see the kernels perched in the hole but there's no loss

 

[netoleon]

That would appear to facilitate the "hasty load" method from Napoleonic ( or earlier ) times. It was, approximately: 1) throw charge down barrel from paper cartridge, 2) thump butt on ground vigorously to force some powder through the touch hole into the already closed pan, 3) spit ball down barrel, & 4) With luck - Kaboom ! Since I doubt a 3F grade equivalent was widely in use back then, I won't speculate on how they discovered this.

Please note that regardless of whether you cone it internally, externally or both - the charges will wind up closer together. My smoothy has an externally coned, drilled touchhole. The maker says he drills all his non-lined touch holes like that. He's made many in his shop like that. It works for me.

 

I too have an externally coned touchhole on a rifle and, in my case at least, I can't tell any difference between it and non-coned touchhole rifles/guns I have in ignition. I am sure the idea is good, just not sure whether it makes that big a difference. Not only does the path to the charge become shorter, but the external cone might 'focus' the pan flash into the hole. What it would seem to do is present a thinner barrel wall that would be quicker to enlarge due to erosion over the years? I have not shot mine enough to tell if that will be a problem.

 

[roundball]

I too have an externally coned touchhole on a rifle and, in my case at least, I can't tell any difference between it and non-coned touchhole rifles/guns I have in ignition. I am sure the idea is good, just not sure whether it makes that big a difference. Not only does the path to the charge become shorter, but the external cone might 'focus' the pan flash into the hole. What it would seem to do is present a thinner barrel wall that would be quicker to enlarge due to erosion over the years? I have not shot mine enough to tell if that will be a problem.

FWIW as just another piece of info, I've got about 1500 shots on each of two rifles that I use the most up at the range, and they have the redesigned vents.

The separating wall is .030", hole is .075", and so far there's not been any change in operating characteristics, accuracy, etc, that I've noticed, so I assume no wear on the vent liners has occurred that would create problems yet. (new liners are only $4.95 a pair)

 

[mikelange]

I've built a number of flintlock rifles, most with internally-coned touchhole liners, three with externally-coned 5/64" vent holes (no actual liners). I own one of each type, one friends owns the other externally-coned piece, and one of my brother-in-laws owns one of the internally-coned guns. Being able to keep fairly close track of how well the various guns are shooting, I can say completely unscientifically that there's no difference in ignition time or reliability that has to do with the method of coning. Sharp flints and clean frizzens dump large showers of sparks, and an adequately-sized pinch of dry priming powder ignites the main charge, end of story.

 

[roundball]

I've built a number of flintlock rifles, most with internally-coned touchhole liners, three with externally-coned 5/64" vent holes (no actual liners). I own one of each type, one friends owns the other externally-coned piece, and one of my brother-in-laws owns one of the internally-coned guns. Being able to keep fairly close track of how well the various guns are shooting, I can say completely unscientifically that there's no difference in ignition time or reliability that has to do with the method of coning. Sharp flints and clean frizzens dump large showers of sparks, and an adequately-sized pinch of dry priming powder ignites the main charge, end of story.

:hmm: guess you better run and tell everybody else they got it all wrong or you have a secret design effect you haven't patented...:grin:

I can tell you with everything else identical at the range...(good Goex, good BEF's, plenty of sparks, etc)...I've unscrewed an old style TC screwdriver-slot liner that has no external cone effect and a longer fire channel as a result of it's depth/thickness to the main...then screwed in the new style TC liner and have a noticeable difference, end of story...:grin:

 

[mikelange]

Roundball --

I think maybe I made a mistake in the description of my guns. None are simply drilled straight through -- the two that aren't internally coned have external cones, thus shortening the flash channel from the outer side. I tried this method as an experiment, intending to drill and tap for internally-coned liners if the external cone didn't perform up to par.

I'm full of opinions and quite a lot of other stuff, but one of those opinions is that the old masters knew better than most of us today how to construct firearms. I follow their lead, for the most part, for the simple reason that they usually haven't been improved on to such a degree as to justify messing with traditional design.

 

[Bob Gular]

Your thinking is correct.

 

[Hoyt]

I coned my smoothbore and it made the lock faster. If it didn't help we probably wouldn't need funnels.