Author Topic: Torch hole location (Read 2795 times)

hortonstn · « **on:** July 15, 2020, 10:57:01 PM »

Should I set this barrel back or is this torch hole location ok?
Thanks

Acer Saccharum · « **Reply #1 on:** July 15, 2020, 11:32:06 PM »

It will work the way it is, but I don't know if the placement will affect reliability and speed of ignition. If you can set the barrel back, I'd do it.

Larry Pletcher (Pletch) did some videos on touchole placement, but I think most of those were about vertical alignment and the impact on ignition.

chubby · « **Reply #2 on:** July 15, 2020, 11:51:39 PM »

Looks like a move of about a 1/32 back would work since you have a liner in , I would move it back like Accer said! not hard to do . Chubby

EC121 · « **Reply #3 on:** July 16, 2020, 12:01:31 AM »

Being lazy, I would round off the bottom of the pan just forward of the hole where it hits the side flat. That would make the pan/side flat joint wider effectively moving the hole back and not affect the frizzen sealing.

Not English · « **Reply #4 on:** July 16, 2020, 01:17:51 AM »

I've been seeing this a lot lately. People quite often seat the breach plug at the length it comes to them without doing any more. Most breach plugs com at about 5/8" in length. By the time you add another 1/8" to it for the touch hole liner, that's working out to roughly 3/4" to the touch hole center. If you measure the distance from the fence to the middle of the pan of the lock, it usually comes out at the 9/16-5/8" neighborhood. You need to shorten the measurements on the barrel to accommodate the difference. The way to avoid this is to cut the inlet in the barrel breach down to a 1/2". The breach plug needs to be a really healthy 1/2", maybe even 9/16" to allow for proper seating of the breach plug in the barrel. If you have someone inlet your swamped barrel, you need to do this before sending the barrel and stock blank to them. If it's just a straight barrel, it's not so important, a straight barrel can just be slid back after fitting the breach plug. this is one of the reasons precarved stocks are such a PIA. There's never an easy way to make adjustments. I am not lumping Kibler's and Chamber's kits in this generalization. They're quality kits made by experienced gun makers. For those that question the safety of cutting a breach plug/barrel fit down, The old timers considered 3 to 4 threads on the breach adequate. With today's better steels this is no longer an arguable concern.

dave

hortonstn · « **Reply #5 on:** July 16, 2020, 01:29:59 AM »

Thanks you guys are great just like having you standing beside me
I've always got a question
Paul

D. Taylor Sapergia · « **Reply #6 on:** July 16, 2020, 01:33:28 AM »

Move the barrel back until you are happy with the hole's location relative to the pan. I think you answered your own question.

Eric Krewson · « **Reply #7 on:** July 19, 2020, 04:44:41 PM »

I would move the barrel back and inlet it just a tad deeper to get a sunset position on the touchhole.

I would imagine, just guessing, that is a precarve with the lock inlet already done. It is a lot less work to inlet a lock completely yourself than to try to fix the mess some precarve lock inlets can be.

smallpatch · « **Reply #8 on:** July 19, 2020, 05:42:16 PM »

Easy fix, slide that baby back an eighth. Looks like it could be just a tad deeper as well. However, if it’s ok on top of the stock, I wouldn’t worry too much about that.

Bob Roller · « **Reply #9 on:** July 19, 2020, 09:16:54 PM »

I know of NO barrel maker that would accept an order for a barrel with only 3 or 4 threads to hold the
breech plug in and don't recall ever seeing an old one like that either. Relying on modern materials to
keep me out of the hospital or mortuary is bad idea and it's just as easy to make the job right.
Bob Roller

Not English · « **Reply #10 on:** July 19, 2020, 10:44:56 PM »

Bob, You obviously did not read my e-mail in depth. If you had, you would have seen that the math does add up. The distance from mid pan to fence is typically 1/2" to 5/8". If you take a 7/8"-14 breech plug and cut it down to 1/2" minimum from the tang, you will still have at least 7 threads left. A 5/8"-18 will leave a minimum of 9 threads with same 1/2". Judging by your comments, you do not proof your guns before letting them go.

It seems like there's quite few good ol' boys here that don't like different opinions. I thought this forum was supposed to be an exchange of information.

Dave

Lucky R A · « **Reply #11 on:** July 20, 2020, 12:06:53 AM »

Hi Dave,
I don't know that Bob builds guns to sell, his expertise lies in machining some very good locks and triggers that have gained a following over many years.
I would believe that you must think that the fence of the lock should coincide with the end of the barrel. This is something that has been argued out before and quick look through Kindig's book or many others will show about as many forward of the barrel end as even with it.
The need to "proof" a barrel has also been argued out, with the conclusion that with today's quality steels and machining there is no need for "proofing." I personally would not send a gun out w/o firing it and adjusting the sights plus trying s number of loads from lighter target loads to heavy hunting loads. I do not want anything malfunctioning in any way.
I have removed a fair number of old breech plugs with coarse threads that were scary short by today's standards, all I can say about that is they did not have the litigation then that we do now. So, I certainly would not go below a 1/2 " of threads in the barrel.
Oh, in the area where I live being "Not English" means you are Amish..
Best wishes
Ron

smallpatch · « **Reply #12 on:** July 20, 2020, 12:34:02 AM »

Ok, once again, we’ve gone from a simple fix, (moving the barrel back a tad) to remachining breechplugs and their depths, to straight barrels vs. swamped, to arguing about lock fences lining up, and number of threads, to barrel steel and proofing.
This was a simple question with a simple answer.

For Pete’s sake, just move the barrel back to center the touch hole, and move on.

bob in the woods · « **Reply #13 on:** July 20, 2020, 12:43:10 AM »

Quote from: smallpatch on July 20, 2020, 12:34:02 AM

Ok, once again, we’ve gone from a simple fix, (moving the barrel back a tad) to remachining breechplugs and their depths, to straight barrels vs. swamped, to arguing about lock fences lining up, and number of threads, to barrel steel and proofing.
This was a simple question with a simple answer.

For Pete’s sake, just move the barrel back to center the touch hole, and move on.

Spot on !

Craig Wilcox · « **Reply #14 on:** July 20, 2020, 12:50:26 AM »

Ron, same here. Not English = either Amish or Mennonite. The only way I got out of this seeming pejorative was to start going to church with them. Mennonites have no problem with owning and driving cars, or using computers - but not socializing on the computer. Research is fine tho.

Having gone to school in London for three grades back in the early '50's, I had no desire to be labelled "English". Not an Anglo-phobe, but it brings back memories of tromping through snow in short pants, and getting my knuckles rapped by the teacher while being taught to multiply and divide in pounds, shillings, and pence! (Boys in Britain at that time did not wear long pants until they became 13.)

Back to the problem - fer cryin' out loud, just move the barrel back just a skosh, about 1/32" would do it.

hortonstn · « **Reply #15 on:** July 20, 2020, 01:56:14 AM »

I moved it back didn't need a lecture there's no way in $#*! I'd shoot a rifle with 3-4 threads
Imho

Dphariss · « **Reply #16 on:** July 20, 2020, 04:32:42 PM »

Quote from: hortonstn on July 20, 2020, 01:56:14 AM

I moved it back didn't need a lecture there's no way in $#*! I'd shoot a rifle with 3-4 threads
Imho

I would have to dig it out and count, I have an original breech plug in the shop with just a few coarse, round threads. If we look to some modern firearms and the surface area of the bolt's load bearing surfaces some would be pretty surprised I think given the pressure levels involved. But these are made of stronger materials than most ML barrels. But if we look the strength of even a grade 2 bolt, then understand the the length of the nut for a given bolt is engineered to be stronger than the bolt. The calculate the surface area of the plug actually under pressure (the are under pressure is less than 1/4 square inch with a 50 caliber bore. If we use the groove say .520 then is a little less than .22 square inches). Not advocating for short beech plugs just pointing out that 4 threads may not be as dangerous as some might think from the pure strength stand point given the load it must bear in ML arms. But if I am intent on putting the fence at or near the breech of the barrel I do it the way the British sometimes did.

It seems the British often put the vent and thus the fence near the breech as well.

Dan

WadePatton · « **Reply #17 on:** July 20, 2020, 06:10:47 PM »

I think "torch hole" is hilarious.

I suppose that was missed by the majority.

Glad you got it moved-I didn't realize barrels came pre-drilled.

flinchrocket · « **Reply #18 on:** July 20, 2020, 07:06:55 PM »

Wade, if you ever accidentally get your finger in front of that hole when the gun goes off and fire scorches the end, you will see that is the correct term.

okieboy · « **Reply #19 on:** July 20, 2020, 07:16:32 PM »

The barrel came "predrilled"? Why would that be?

Not English · « **Reply #20 on:** July 21, 2020, 03:25:00 AM »

Ron & Craig, "Not English" is a hard earned rendezvous name. It took a whole lot of drinking while being the lone Frenchman with a bunch of Roger's Rangers at a rendezvous one time.

Craig, I can empathize with English schooling. I went to school in Edinburgh, Scotland in the early "60's. They didn't rap the knuckles, but used a thick leather belt across the palms.

Dave

WadePatton · « **Reply #21 on:** July 21, 2020, 03:50:38 AM »

Quote from: okieboy on July 20, 2020, 07:16:32 PM

The barrel came "predrilled"? Why would that be?

I assumed it was a kit thing. But now that I think on it I get it. Hole goes where it goes, It's the pre-inlets giving the issues.

WadePatton · « **Reply #22 on:** July 21, 2020, 03:54:31 AM »

Quote from: flinchrocket on July 20, 2020, 07:06:55 PM

Wade, if you ever accidentally get your finger in front of that hole when the gun goes off and fire scorches the end, you will see that is the correct term.

yep, I wouldn't want to light my Luckies that way.

flinchrocket · « **Reply #23 on:** July 21, 2020, 06:51:28 AM »

Not only is it hot, it feels like a sandblaster. It will turn your skin black quite fast.

BOB HILL · « **Reply #24 on:** July 21, 2020, 03:49:18 PM »

I always thought touchhole was a corruption of torchhole, since this is where the fire gets to the charge.
Bob

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Author Topic: Torch hole location (Read 2795 times)

chubby