What size touchhole?

[Stubert]

Just curious, what size touchholes do you all have? I've got 2 rifles. One has a liner that was .040 new. I's now 5/64 (078), The other rifle has just a hole in the barrel that was 078 when I got it. My pedersolli harpers ferry pistol came with a huge 3/32 hole new.

 

[DrTimboone]

5/64" :grin:

 

[paulvallandigham]

The 5/64"( .078") should be big enough for most locks. Location of the touch hole enters the picture beause its important for ignition that the hole belocated above the pan so that the heat of the flame from burning the priming powder rises to enter the vent. Then clear a hole into the main charge in the barrel by running a vent pick into the hole, before priming, and you should be assured of quick ignition.

Always check to see that the sparks are actually being thrown into the flashpan. Not dropped, not pouring down the face of the frizzen, but THROWN into the pan. Hold the gun, empty out in front of you and trip the trigger with your thumb, so you can look at the lock from the right side to see how the frizzen opens, and where the sparks go.

 

[Mike Brooks]

1/16"

 

[djnye]

.45 cal. using fffg powder is 1/16"

take care, daniel

 

[roundball]

Mine are .075...right at 5/64"...incredibly fast

 

[robinghewitt]

According to Ezekiel Baker, for a rifle, "nearly the sixteenth part of an inch", for a musket, "the sixteenth and one thirty-second part of an inch" :thumbsup:

best regards

Squire Robin

 

[paulvallandigham]

Touchholes create more arguments over less than any other aspect of flintlock design. Many are drilled 3/32". Others claim 1/16". And, then there the fans of the wider 5/64" holes. I drilled mine out to 5/64" a while back when I was still having trouble with the 1/16" hole in damp weather. I have had no misfires with the touch hole enlarged to 5/64".

Now, the differences in this argument represent 3/64", not really much when you think about it. I believe that the touch hole location in relation to the pan is more important than the differences between these three size holes. The hole needs to be above a line drawn across the top of the pan. That allows air to exist under the hole, so that the heat of the flame goes into the hole, and is not above it.

As a matter of long practice, I sitll bank my priming powder away from the touch hole to give extra air next to the hole to draw the flame to that " free oxygen " . Its the heat, and not the fire that ignites the powder, and I have found that banking the powder away from the hole speeds up ignition.

I do believe that an inside coned liner contributes to speedy ignition, too, simply because it allows the heat to contact more granules of powder, and then reflects the heat of the burning charge back toward the chamber to raise chamber pressures and speed the burning of the main charge. A parabolic cone does this better than a straight walled cone. Outside coned liners will move the prime closer to the main charge, but the distance to be traveled is so small that I don't believe this contributes very much to ignition speed.

Paul

 

[DrTimboone]

My White Lightnings were shooting fine as they were delivered, but after reading all the discussion on another thread a few weeks ago I went ahead and ran a 1/16" bit thru the holes and then took my countersink and hit the outside of the hole by hand just to eliminate any lip etc. I then found I could actually get a a 5/64 bit through the hole tightly..... My rifle with the Chambers early English lock fires instantaneously!! :thumbsup: Of course that is after being properly picked and with just a light layer of fffg on the bottom of the pan!! :blah:

 

[Larry Pletcher]

My White Lightnings were shooting fine as they were delivered, but after reading all the discussion on another thread a few weeks ago I went ahead and ran a 1/16" bit thru the holes and then took my countersink and hit the outside of the hole by hand just to eliminate any lip etc. I then found I could actually get a a 5/64 bit through the hole tightly..... My rifle with the Chambers early English lock fires instantaneously!!

Your experience compares well with the timing I did. I think you and I were on the other thread. I liked the 5/64 for its speed and the exterior cone, however slight, improved consistency. I did not combine the 5/64 and the exterior cone in the same trial, so I appreciate the anecdotal exidence.

Regards,
Pletch

 

[Vaino]

Optimum touch hole size would depend on the type of TH....if a liner is used, what kind of liner, staight hole, length of the actual hole, etc. I presently use the "White Lightning" and if properly installed, yield nearly instantaneous ignition. I enlarge the factory hole w/ a #51 drill {.067} and that along w/ the excellent interior funnel and extremely short land produce ignition times that are unbelievable. Previously, I made my own TH liners and they were fast, but nothing like the "White Lightnings".....Fred

 

[ffffg]

i was having trouble with the 51 bit hole in my chambers mark silver .62 rifle.. i asked and pletch said to go to .070 with a verry slight hand turned countersink.. , and the gun has fired flawlessly, and instantly since being carfull to have good flint, no oil on the frizzen face etc.. .. dave..

 

[mbritt]

The new fowler that I bought last year had slow ignition so I drilled the touch hole with a #48 drill (.076) and it made a tremendous improvement and worked well as long as I didn't fill the pan past half full of Swiss FFF.

This year I got brave and ran a #46 drill (.081) through the touch hole and it made yet another tremendous improvement. Now the ignition really is instantaneous (to my senses) and it doesn't seem to make any differnece if I fill the pan 1/3 full or 7/8 full of FFF. I also stopped poking the touch hole with the pick before priming and so far havn't had any misfires.

 

[DrTimboone]

Be careful for the man on your right!! :bow:

 

[Herb]

I had a flash hole that size (about .080 something) drilled through the Colerain barrel of my Issac Haines .40 that I made from Track's parts. Swiss 3F would leak out that hole when I loaded. You might not know it is happening unless you leave the frizzen closed once when you load. Bet you'll find your pan full. So I drilled center on the side flat and fitted a 5/16 White Lightning liner. That hole was higher than the top of the pan. Had to cut the hole down a little with a carbide dental burr in my Dremel tool. Didn't want it bigger than about .070 or so. Works good.

 

[mbritt]

Today I loaded the gun with the frizen closed and then thumped the butt of the gun on the ground a few times to see if that would shake some powder out, but I found no powder in the pan. I'm sure 3F would leak through the hole, but with 2F this large touch hole works great for me.