Touch hole liners??????????

[Majorjoel]

 I have always used touch hole liners in my flintlock builds. I have to admit, from the inner most recesses of my common sense instincts find them to be "a bug in the ointment" . Of all of the special skills learned to construct a mechanically flawless longrifle I have lost more sleep over that darn little hole in the barrel wall.  On occassion have had to drill into the breech plug face in order to get better aft lock placement. When you think about it, the effort is all just to facilitate the liner, not the touch hole! Where is the logic here! I have not only made the barrel a bugger to clean, but now the liner and breech plug are mechanically locked together. When it comes to a New build, a liner is really a dumb idea mechanially speaking. They do have a logical place when used for conversions and repairs to oversized vents. In the future, I'm going to experiment with direct barrel vents. Thats my 2 cent opinion on this subject.

[T*O*F]

They do have a logical place when used for conversions and repairs to oversized vents.

Somewhere I have a period reference on "rebouching" a touch hole.  In essence it says to drill out the eroded touch hole, thread in a piece of silver wire, and redrill the hole thru the wire.  It did not mention size, but gives the impression that the liner is not substantially larger than the hole, as opposed to the humongous liners used today.  It also did not mention is the original touch hole was internally coned or not.  I think modern liners have their roots in the conversion of flint guns to percussion using the drum method, which explains their large size.

[rich pierce]

The liners on finest 18th century guns and the later "pinnacle" doubles by mantons etc all were large platinum or gold liners.  We admire and rightfully laud the work of the finest makers but science is science and they did not have the timing devices etc we have now.  The markets were extremely competitive in the late flint period for best work, and many gimmicks were deployed which do nothing at all, like roller frizzen springs.  We reason that since they appeared on the best work, and they were advertised as providing surer and faster ignition, it must be so.

Data for example shows that patent breeches do nothing to aid ignition.  They may boost pressures and velocity, but ignition speed is unaffected.  It's hard to unlearn what we were taught was fact.  Since that is the case, then everyone will continue to use liners, because customers want them.

[Dphariss]

The liners on finest 18th century guns and the later "pinnacle" doubles by mantons etc all were large platinum or gold liners.  We admire and rightfully laud the work of the finest makers but science is science and they did not have the timing devices etc we have now.  The markets were extremely competitive in the late flint period for best work, and many gimmicks were deployed which do nothing at all, like roller frizzen springs.  We reason that since they appeared on the best work, and they were advertised as providing surer and faster ignition, it must be so.

Data for example shows that patent breeches do nothing to aid ignition.  They may boost pressures and velocity, but ignition speed is unaffected.  It's hard to unlearn what we were taught was fact.  Since that is the case, then everyone will continue to use liners, because customers want them.

The Nock breechI made for Larry to test WAS slightly slower than the flat breech but it was more consistent. They were developed for WING shooting and wing shooting requires consistency or there is no way the provide the proper lead.
I use liners because I do not consider simple vents to be as reliable.

Dan

[Larry Pletcher]

Dan and all,
Help my memory here.  I seem to remember reading somewhere that a breech like Nock's was designed for a specific granule size.  Prpbably work well with one size but might be a pain with another size.  I don't know more specifics; may have read it here on ALR when we were timing breeches.
Regards,
Pletch

[Pete G.]

I use liners because I do not consider simple vents to be as reliable.

Dan

I agree wholeheartedly.
I am after real world reliability. I go to the range to shoot; not to putz around with a little hole in the barrel.

[JTR]

TOF,
I've had a couple rifles with reboushed touch holes, and they were only about an 1/8", or maybe a little larger in diameter, so yes, smaller than the liners used today.

John

[Dphariss]

TOF,
I've had a couple rifles with reboushed touch holes, and they were only about an 1/8", or maybe a little larger in diameter, so yes, smaller than the liners used today.

John

I made a lot of them from 10x32 stainless set screws and still make them similar but use left over stainless rod.
By "ear" they are as fast as a WL by slightly slower by actual timing.

Dan

[Joe S]

I've had a couple rifles with reboushed touch holes,

Do you think these new 1/8” touchhole liners had straight holes, or do you think they were coned on the inside? 

[jwh1947]

Thanks Larry, et al.  This turns out to be a truly educational thread.  I'm learning.  Now, while we are on the subject, am I totally off here or is there something to consider with the following.  Flints vs. percussion.  Speed the question.  Say you have that flint hitting well to the top of the frizzen, sparks shower and the pan is blowing off before the cock even comes to a rest.  The percussion cap needs to be hit at the bottom of the fall.  Could this be something to consider to minimize the old "hiss, boom" issue?  Should I check myself in for a checkup from the neck up, or just a minor med adjustment?  Wayne

[Acer Saccharum]

Wayne, your flint beliefs will flip head over heels if you watch some of Larry Pletcher's high speed movies on flint ignition. Essentially, the sparks land in the pan, and they sit in the powder until it starts to burn. The movement of cock and frizzen is long over before the priming takes fire. The wive's tale about the sparks lighting the prime as the flint is still sliding down the frizz is just not supportable.

http://www.blackpowdermag.com/featured-articles/new-high-speed-video-from-friendship-09.php

Enjoy!
Acer

[Larry Pletcher]

Thanks Larry, et al.  This turns out to be a truly educational thread.  I'm learning.  Now, while we are on the subject, am I totally off here or is there something to consider with the following.  Flints vs. percussion.  Speed the question.  Say you have that flint hitting well to the top of the frizzen, sparks shower and the pan is blowing off before the cock even comes to a rest.  The percussion cap needs to be hit at the bottom of the fall.  Could this be something to consider to minimize the old "hiss, boom" issue?  Should I check myself in for a checkup from the neck up, or just a minor med adjustment?  Wayne

Hi Wayne,
This is the fun stuff.  We have learned much about flint ignition in the past 3-4 years.  During that time I had the chance to work with reps from Olympus filming locks at 5000 frames per second.  Played back, this results in a film 167 X slower than normal.  While I have timed locks for 20+ years, this slow motion video really taught us bunches.  In all we filmed 70-80 locks – some locks multiple times, using different powders, up-side-down etc. 

One of the things we learned was that at NO time did the lock ignite the pan before the flint came to rest.  Another is that the sparks do not accelerate away from the flint/frizzen. Instead the sparks appear to be rolled down the frizzen.  Sparks from high on the frizzen and sparks from lower down appear to reach the pan together.  After seeing these locks on frame by frame software, I’m firmly convinced that the rumors of locks so fast that they ignite the pan before mechanical movement is done are wishful thinking.  It just doesn’t happen.  In many of these videos we counted the frames from "flint end movement" to ignition and were amazed at how long it took.

Below I included a few links to these slow motion videos of locks firing at 5000 frames/second.  You can see how long it seems to take AFTER the flint edge stops.  In many cases the pan doesn’t ignite until after the frizzen rebounds once.  (That was another thing we learned – frizzens rebound on the best of locks.)

http://www.blackpowdermag.com/featured-articles/new-high-speed-video-from-friendship-09.php     2009 spring shoot

http://www.blackpowdermag.com/featured-articles/more-high-speed-video-from-friendship.php    2007 spring shoot

That is a brief description; I can get carried away with this stuff.  Acer, I just saw that you beat me to the punch.  Guess I am too long winded. 

Regards,
Pletch

[Bill of the 45th]

OK, so Larry's testing has shown us that the smaller the grain size the faster the powder burns, thus all things being equal, and using finer prime should get us the fastest ignition assuming lock time is always the same.  So the distance from the point of ignition of the prime to the charge will be the true total ignition speed.  The farther the distance the slower the boom will happen.  More time for flinch, and for sights to wander affecting accuracy.  So if we put in a coned liner that would shorten the distance to the charge, and increase the speed of the boom.  If this thinking is true, couldn't we just cone it on the outside, and achieve the same.  Does this make sense or am I having a blonde moment.

Bill

[Larry Pletcher]

Bill,
You're right.  Steve Chapman and I have tried variations of this.  Depending on how you install a Chambers liner you can use a mild exterior cone.  the catch is that the web is thin to begin with; it would be easy to get carried away and cut through the web.

Dan P sent us a liner with a pronounced exterior cone.  In my straight cylinder vent article I found that a 1/16" hole with an exterior cone was better than a 1/16" hole with no  exterior cone.  I think in Dan's case he did in on purpose.  On mine I wanted to cut away the burr, saw what I liked, and went deeper.  Regardless of where the cone is, the closer the pan fire is to the barrel charge, the better we'll like the result.

Regards,
Pletch

[Captchee]

  yep  what larry said .
a flintlock being faster in ignition then a cap lock , has pretty much been  disproved .
 That being said  though . A good properly set up flint ignition can be so fast that the  shooter cannot tell the difference

[JTR]

Joe S, I don't know if they were coned on the inside as I never removed the breech plug to look. As much as I enjoy taking old guns apart, some things are better left as is, unless there's really a need to remove it.

Pletch, I don't think you can ever be too long winded. I really enjoy the videos and the work you've done!

John

[Acer Saccharum]

I know this: a fast flinter is fun. A slow inconsistent flinter is not worth the powder you put in it.

Larry's dedication to understanding flint ignition has allowed me to improve my flinters to very reliable and fast ignition times. This has added a lot of 'fun factor' in the shooting game for me. Thanks, Larry.

Tom

[California Kid]

JWH, maybe the Dr. would give you a checkup in your bunker! HA! HA!

[LURCHWV@BJS]

       I for one am glad this subject came up, being that while I am still working on my first build I am still making decisions on the applications I will use.  I have often wondered about touchhole liners, why were they used?  when did they start using them? I've not seen to many, if any at all on any antique flinter I've seen.  I was going to put a liner on my first build, just in case I learn I don't like using a flinter it could easily be switched to percussion.

   I am now reconsidering my decision.  I will now be going traditional.  Thanxfor all the arguments they really opened my eye's


                Rich

[Don Getz]

Larry's photos have gone so far beyond what we shooters can conceive, or detect in shooting.   For many it may not seem
like any difference in ignition between merely drilling a holel in the barrel, or using a white lightning, but, in actuality, there
is a difference.  If merely having a hole drilled in the barrel for a touchhole, you "must" keep it clean to get adequate ignition.    If you think about this scenario, it only makes sense that flame, or heat, whatever, will get to the main charge
quicker if it only has to go about 1/16", as in a white lightning, versus having to go nearly a quareter of an inch thru a drilled hole.   On the other hand, the first gun I built was with a Doublas barrel, 7/8" straight in 45 cal.   I shot this gun a
lot with merely a hole drilled for a touch hole, and it worked fine.   Perhaps I was new to the game and didn't realize how
slow it was ??   Maybe Larry's photo's have merely confused people, and made them think too much (joke).  In line
with his photo experiments, it made me think about this.....Steven Wright made the comment....."If you could drive your
car at the speed of light, would the headlights work?    Don

[Dr. Tim-Boone]

The old guns had not read Larry's articles yet......... they didn't know they were supposed to be slow...........now the cat is out of the bag. .......see what science and education can do........

[T*O*F]

I have often wondered about touchhole liners, why were they used?

By its very definition, a "liner" is something used to repair an existing hole.  This is the reason why they were used.  A touch hole liner repairs a touch hole that is out of specs.  This is why I mentioned the historic reference to "rebouching" a touch hole since that's how they were always repaired.  It's also why I posted the link for the internally coned touch hole.

The old builders were not dummies and realized that internal coning would speed up ignition, but this research was not yet available in the 20th century when guys started building guns.  They just assumed that a straight hole was drilled in the barrel, and soon discovered themselves that ignition was slow, which in turn propogated the myth that all flintlocks were slow.  Then some unknown, enterprising genius discovered he could turn a coned liner and speed up ignition.  Thus this unknown genius re-invented the wheel, but in a different manner.  This information had been lost between the flint period and modern times, and as far as I know, no person has ever purposely taken apart original guns to inspect for this because you just don't go around debreeching collectible antiques just to peek inside.

In a similar manner, one cannot say they are slower because Larry has yet to time any guns with internally coned touch holes.  Both Gary and Wayne have called for sound research in the study of guns, but one can easily see that the longest discussions are usually full of conjecture and opinion rather than sound research.  Likewise, most people do not possess the problem solving skills required to interpret this research which is why we see so many anecdotal opinions expressed.

If anyone truly wants to know how guns were built back then, I would suggest you acquire a copy of "ESPINGARDA PERFEYTA or The Perfect Gun" first published in 1718 by 3 Portugese gunmakers to expose and make public the "black arts" of gunbuilding which at the time were closely held secrets.  It's 1st person documentation which has been translated into English but it's a hard read because the translation reads like a high school Latin translation of Caesar's Wars.  Originally written in old Portugese, an extinct language, some of the terms required modern words because the original meanings are lost in history.

[Dr. Tim-Boone]

I was recently looking at some signed 18th century guns made by masters.  Now I don't know if the touch hole treatment was original, but one had a liner and one appeared to be coned on the outside.......

I don't think that a liner is "by definition" a repair. Bushings are used as original design in many machines. Many high end English guns of the period appear to have been made with liners........Now this doesn't mean that they haven't also been used for repairs...... Nor that they weren't reinvented as TOF suggests....I just don't think there is one answer that fits every gun!   The coning make sense to me ...however you do it.

[jwh1947]

Thanks.  California Kid...a great idea.  Now looking for a 40-something female internist who does bunker calls.  Don, Einstein pretty well answered the headlight question.  Otherwise, I am presently revising my narrowness regarding liners.

Here is what I've learned or begun to think so far.

1.  I must move beyond the notion of the initial sparks being of much importance.  The photographic evidence is most compelling.

2.  I do believe, by the same photographic evidence, that it is actually the heat of the major pan blast that sets the main powder charge.

3.  There appears to be a relatively large standard deviation/variance in pan ignition.

#3 might be the devil in the details or the fly in the ointment of lots of folk wisdom and empirical experience.  See, the applied science is out there to add to our understanding.  Most respect to all contributors. Wayne

PS: Come to think of it, the masters at Jacobsburg all emphasized "not surely knowing when the gun was going to go off and following through with sight picture during the hiss and boom."  This has never changed as we learned same thing at Camp Perry with cartridge rifles, but there was no hiss that we could notice.

[D. Taylor Sapergia]

I have examined one rifle by an obscure maker called John Rupp in which there is definitely a liner as we know it.  It is not a re-conversion...the lock is original to the rifle, so it is not to replace a drum.  The breech and liner are corroded precisely the same, except that the barrel arrears to be of a softer material, since it is shrunken ever so slightly around the liner.  The hole is not blown out large like a lot of original flintlock rifles are.  The liner almost completely fills the side flat, and the vent is precisely centred and level with the top of the pan.