Touch Hole Liner Dangerous?

[chuck-ia]

I think the white lightning liners come in 1/4 by 32 ?? 5/16 by 32 and 3/8 by 32, my way of thinking is 1/4" by 28 is a common thread, considered a fine thread. I could be wrong though. flinch

 

[redwing]

Paul is right on. This is a long standing dislike for Chambers. These folks will get radical if you mention his name. Fact is most shooters who have the Caywoods will buy a liner sooner than later. :hmm:

 

[denster]

Flinch is right 1/4X32 is not so common. That thread is used on the white lightning as the root diameter of the thread is less than 1/4X28 allowing for a slightly larger chamber.

 

[Mulebrain]

Here is a pretty good read on liners etc...

Flints, Frizzens and Touch Hole Liners
by Charlie Maggard

Usually the attitude is, "If there is a hole through the barrel to the main powder charge the rifle will fire just fine." This is true, but the results may not be what you desire. A proper touch hole (vent) liner is critical to the speed that a flintlock will fire. I like permanent touch hole liners in my rifles. My experience has been that the liners with screwdriver slots or the hex head screws tend to collect fouling and slow down the ignition. I like the type that requires using a nipple wrench for installation and filing off the excess lug so it's flush with the barrel flat. Why remove the liner anyway? The more times you screw a liner or nipple in and out of your rifle or pistol, the looser it becomes. This common practice stresses and wears the threads and increases the possibility of cross threading. That will lead to failure. All of the "blow outs" of liners and nipples that I have witnessed are the result of shooters frequently removing and reinstalling these items. To replace a permanent liner, just drill out the hole in the liner and remove it with an Easy-Out.
http://www.muzzleblasts.com/archives/vol4no1/articles/mbo41-3.shtml

 

[Tom Compton]

Great Point, Sir Michael! I over looked that obvious technicality.
TC

 

[tg]

"Kit Ravenshear once told me a vent liner was a repair item and he wouldn't install one on a new firearm'

I would agree with that, liners were used but were not common on most types of guns, and I have found that they are not really needed, a plain hole coned a bit on the inside has worked very well for me. It is rather amusing as mentoned above that a PC driven hoby group has pretty much looked the other way with the use of liners just to get a bit more speed...kind of like using a modern bullet to increase range and Ft/lbs at target it is hard to figure going to all the cost and time to get the details as close as possible then ignore an item that is very easy and inexpensive to make a PC choice about, I guess everyone sees PC/HC from a different angle, or through a different hole. :hmm:

 

[lonehunter]

pardon my ignorance, but how would one cone the inside of a vent if it was just a hole in the barrel?? is there a tool for this? if so, how does it work? :v

 

[rabjr]

pardon my ignorance, but how would one cone the inside of a vent if it was just a hole in the barrel?? is there a tool for this? if so, how does it work? :v

Believe it or not it can be done with a hardened nail I believe. I think Stophel has pic's of the device and know how if I'm not mistaken.

 

[texcl]

Yes there is,it is a little flat piece of hardened steel that has the cone shaped cutting surface on one end and a touch hole sized nub on the other, it is inserted inside the barrel through the touch hole while it is unbreached and a drill is then chucked to the nub that sticks out of the touch hole,and you cut the cone out. I'm sure someone else here can explain it better with pics., it is really simple.

 

[lonehunter]

ok, i get it now. thanks :v

 

[Stumpkiller]

You can also do it from the other side and then plug the access hole.

I guess 1/4-32 is the oddball. They're not 1/4-28. Sorry. That's Zerks and nipples.

I'm new to this senior moment stuff but catching on fast. :shake:

 

[JV Puleo]

True enough. Bushed touch holes are reasonably common on American guns. I have several myself, one of which is a Henry Pratt rifle (ca.1820) thats my favorite flintlock shooter. But, in every case I have seen on an original American used flintlock, the bushing is much smaller than the conventional screw-in liners. In fact, I've seen very few as big as a 1/4" in diameter and in those cases on guns where is was likely the barrel was being reused and the purpose of the bushing was to move the touch hole rather than repair it. When I have seen a bigger bushing, with the hole in the center, it has always been on a re-conversion and thus made to disguise the large hole made for the drum.

The modern liners are tapered from the rear. I don't think this was the case with the gold and platinum liners but I confess to never having tried to take one out. Since they weren't designed to be removed, I presume they would be destroyed in the process. I did do a test on the touchole of a nearly unfired Charles Grierson British Officers musket (ca.1796) which has no bushing and found that the touch hole was tapered from the outside in. I don't have my notes handy but I was able to identify a small taper pin reamer that came very close to the original dimensions. (I used a sequence of small wire gauge drills to test depth and diameter.)

 

[Zonie]

The 1/4-28 thread is the standard fine pitch thread and is designated as 1/4-28 UNF (Unified National Fine).

Most of the vent liners made use either the 1/4-28 UNF or 5/16-24 UNF or 3/8-24 UNF.

To the best of my knowledge, Chambers is the only one that uses the 1/4-32 UNEF (Unified National Extra Fine) thread.
They use this extra fine pitch thread because it allows them to make a slightly larger cone inside the liner than the courser 24 pitch thread would allow.

As to the dangers of using a vent liner, there is none provided the threads in the barrel are properly tapped.

Also, as was mentioned, the lower area of the vent liner is covered by the lock plate so even if the threads failed (which they won't) the liner would have to blow the lock plate out away from the barrel before the liner could escape.

As for standing next to a person firing a flintlock with a liner, the same words of wisdom should be given to anyone standing next to a flintlock being fired without a liner in the barrel.....DON'T.

 

[Capt. Jas.]

Yes there is,it is a little flat piece of hardened steel that has the cone shaped cutting surface on one end and a touch hole sized nub on the other, it is inserted inside the barrel through the touch hole while it is unbreached and a drill is then chucked to the nub that sticks out of the touch hole,and you cut the cone out. I'm sure someone else here can explain it better with pics., it is really simple.

I use a cutter somewhat like this but it is not a flat piece of metal. It is a rounded cutter with multiple cutting edges. It works like a champ and the gun goes off like it has a white lightnin liner in it. The size of the cutter will allow the use of a white lightnin if the hole ever burns out.

 

[denster]

I am at a loss to understand how these tools work. Maybe I'm misunderstanding the principal. The tool is inserted into an unbreeched barrel and the shank goes through the touchole and is gripped on the outside of the barrel by a drill chuck and turned to cut the interior cone. I can understand how this might work on a 58cal or larger barrel no more than 1" at the breech but you would sure have to be gentle with that .062 shank.
I understand what one poster said about comming in from the opposite side of the barrel and then plugging that hole. I could understand also using a ball cutter comming in from the breech parralel to the bore and cutting a concave enlargement.
What am I missing here?

 

[Dphar]

This was on the Caywood Guns website, I've never heard of this before. Anyone see it happen before?



Please be advised that installation of a touch-hole liner will void any and all warranties. We cannot work on a barrel which has a touch-hole liner. The only solution to any problem encountered will be to replace the barrel. Touch-hole liners are unnecessary and they ARE DANGEROUS. After years of use, with gas erosion and replacement-removal wear, the threads will no longer hold the liner in the barrel and it WILL BECOME A PROJECTILE WHICH CAN KILL OR MAIM A BYSTANDER. Your gun will not ignite faster with a touch-hole liner. A properly coned touch-hole will ignite almost instantaneously without any problems that are associated with liners. Please be advised not to stand next to any shooter using a touch-hole liner in any gun.

Its BS. I wonder if he makes the same statement about removing nipples from percussion guns.
Its like anything else if its done right its not a problem, though I don't like large diameter liners in barrels or removable liners.
A blanket statement about liners is simply silly.
The Caywood site has a lot of good information but this is not in that category.

Dan

 

[Mike Brooks]

Yes I am aware of how liners were made and of what material in English "Best" guns. The comparison is not a stretch. A liner is a liner whether it is screwed in place or brazed. The point being that liners while seen as a feature on a new British gun. Was not commonly found on a new gun made in the Americas it was however a means of repairing a gun whose vent had become enlarged.

English gold liners were but in like a rivet, there are no threads what so ever.

 

[Dphar]

Flint, one of the guys at our club actually had a nipple blow out of the bolster on his CVA Kentuckian, it turned out he was in the habit of removing it at every cleaning, and had worn the threads..no one got hurt..and I agree, Caywood is involved in some kind of CYA...Hank

Dollars to donuts he cross threaded it and damaged the threads in the bolster - that is what caused the problem, not removing the nipple. It is common practice to remove the nipple every time you clean a percussion gun and will not cause a problem if it is screwed back in properly. Cross thread it and you have ruined it and all bets are off. As far as a touch hole liner? Like Paul said, I wouldn't remove one, it won't be a problem.

Lots of things can cause this manufacturing "Tolerance" is one.
Poor percussion breech design is another.
A friend blew one out of a Bill Large breech years ago and I had one come out of a DGW Belgium made "Squirrel Rifle" back about 1967/68.

Dan

 

[Mike Brooks]

I'm hard pressed to understand how a touch hole liner can become projectile. I've never seen one that is fully exposed. All of the liners I've seen are between 30-50% covered by the lock pan. For one of these to be blown out would require sufficient force to shear the liner length wise leaving the remaining part captured under the lock pan. :shocked2: Or it might blow the whole lock off which I sincerely doubt is possible even for one with a single lock bolt. :hmm:

This has happened locally about 15 years ago with a centermark TVLLE. It involved lots of beer and a massive overload. Blew out the 1/4" X 28 liner and took the lock out with it completely destroying the stock. The barrel seemed to be otherwise unharmed. The shooter was also unharmed which seems to be typical luck of drunks.....

 

[misher]

Maybe in that case it served as a safety device and blew before the barrel exploded.