Drilling a Touch Hole

[robstock]

Hi,

I have a .32 caliber barrel for a kit rifle I was given. i noticed there is no touch hole drilled. So my question is should i drill and tap for a liner to be installed or just drill the appropriate sized touch hole? I have read several comments on this and seems there are mixed opinions on this.

thanks for any input.

 

[jimdvan]

To me it seems that using a coned liner puts your main powder charge just a little closer to the pan for better, faster ignition.

 

[rich pierce]

Do you want best ignition, or a most authentic method? A touch hole liner coned on the inside will improve ignition consistency. It will also look different from originals if you use a stainless steel or ampco liner. Chambers offers plain steel liners, which I prefer. Yes, they need replacement every 5000 shots or so.

 

[robstock]

Thanks for the input. I will more than likely go the route of the liner.

 

[ZUG]

I think hands down a vent liner is the best way to go. For me it does not matter if the liner is stainless steel, Ampco or just steel as long as I get the best ignition from the liner.

 

[Sean E Bug]

I just drill the hole. if the gun has an issue down the line a touch hole line can be installed but I don't see the need for it right away.

 

[deerstalkert]

i usually just drill a vent hole, then later if ignition is a problem may install a liner.
remember with just a 1/16 vent hole it should be forward of the face of the breach plug a bit. i always drill mine after the lock is inlet so i can adjust fore and aft as needed if needed. initial layout should make it fairly standard, but nothing about a plank build is standard!

 

[Eric Krewson]

Install your lock first to locate the correct position for your liner. Most of us use a liner, I like the real Chambers White lightning liners not the TOW version. On a .32 I would use a 1/4" liner and have the edge of the liner just barely off the breech plug face.

https://www.flintlocks.com/parts.htm
I do a lay out like this and drill a 1/16" pilot hole first to make sure tap drill goes in the right place. This is a big barrel, the liner is a 3/8" one.

 

[tenngun]

Old guns often had just a straight hole. That works but will be a little slower than a liner. Above it’s noted that a plain steel liner burns out and has to be replaced after several thousand shots, I don’t shoot that much
Liners were placed in old guns, so not non historic, just not real common.
I’ve shot both and like a liner
There were tricks done on old guns like coneing outside and inside.
My favorite is the white lightning

 

[M. De Land]

Hi,

I have a .32 caliber barrel for a kit rifle I was given. i noticed there is no touch hole drilled. So my question is should i drill and tap for a liner to be installed or just drill the appropriate sized touch hole? I have read several comments on this and seems there are mixed opinions on this.

thanks for any input.

The trouble with designing a flash hole without a liner is eventially when a liner will be needed the threads will intersect the breech screw. I believe the best way is to plan for an evetially liner body is to design so that it will clear ahead of the breech screw which means the tang mortice and barrel shoulder will have to be set back to account for it allowing a pan center locate.
The flash is going to be a main charge side ingnition anyway even if just ahead of the breech plug and I see no accuracy disadvantage to this as long as it will be below the patched ball seat.
I say this from experience using underhammer percussion match rifles which are virtally all side main charge ignition. I can't tell any difference in accuracy or reliability if the flash hole is just clear of the breech plug or a liner thread width ahead of it.
A side note on flash hole profile, it's not just the inlargement of them that causes issues it's also the irregular way they erode that causes inaccuracy and reliability trouble.
I think in general flash hole profile erosion is tolerated way past when they are effecting accuracy and eventially reliability.

 

[M. De Land]

The trouble with designing a flash hole without a liner is eventially when a liner will be needed the threads will intersect the breech screw. I believe the best way is to plan for an evetially liner body is to design so that it will clear ahead of the breech screw which means the tang mortice and barrel shoulder will have to be set back to account for it allowing a pan center locate.
The flash is going to be a main charge side ingnition anyway even if just ahead of the breech plug and I see no accuracy disadvantage to this as long as it will be below the patched ball seat.
I say this from experience using underhammer percussion match rifles which are virtally all side main charge ignition. I can't tell any difference in accuracy or reliability if the flash hole is just clear of the breech plug or a liner thread width ahead of it.
A side note on flash hole profile, it's not just the inlargement of them that causes issues it's also the irregular way they erode that causes inaccuracy and reliability trouble.
I think in general flash hole profile erosion is tolerated way past when they are effecting accuracy and eventially reliability.

Thinking on this a bit more about the underhammer ignition example I have to say reliability is better with some space between the breech plug face and the nipple orifice intersection as it has more fouling clearance.