Vent

[54ball]

Hi All,
Ive been researching flintlocks hot and heavy for the past few months. I have read the some custom makers do not like vent liners and consider them a safety hazzard. They will not work on one of their barrels if a liner has been installed. They also say a properly coned vent hole is period correct for the 1700s and safer. What are your opinions of a drilled vent vs. a liner. For a nonvice like me a drilled vent seems easier to do than installing a liner. If it erodes, a liner can always be installed later.

 

[robinghewitt]

The only original vent liners I have seen were either gold or platinum and on posh English shotguns.

The concern with a plain drilled touch hole is that it will either fill with powder and burn like a fuse, delaying ignition of the main charge, or, being empty of powder it will block the pan flash from the main charge by being long narrow and damp. Causing misfires.

If your barrel wall is thick and touch hole length is a problem for you there are two ways to fix it. Either open out the hole from the bore side (tricky period method) or add a liner (easy modern method). The liner has to be stainless or it will erode open in short time, that's why the originals were gold or platinum.

The main problem with the easy modern method is that the drill used to install a liner is much bigger than the original designer intended, and it ploughs into the breech plug causing much cussing, filing and damage limitation effort.

Whatever floats your stick really.

 

[cmetucker]

54 Ball,

Go with the drilled vent (5/64 if you are thinking of a larger bore gun) with a slight outside cone. I consider a vent liner to be 'functionally never' correct for an original American longrifle. High end European guns are another matter as Robin alluded to. Consider the vent liner to be a viable and correct repair to extend the life of a gun with a burned out hole, but not needed on a new barrel.

Ignition time on my longrifle with a Chamber' round faced English lock, feels as fast as ignition time of a 30-06 for the first few shots (does seem to slow a bit as every thing gets duller, dirtier, and fouled, but that is during extended range sessions, with shooting far beyond what you would do on any one, or several hunts).

I do think a vent liner is perhaps a bit of a weak point in a barrel, but there in nothing that I have ever heard of to suggest that they are at all unsafe (the breach plug is also threaded into the barrel).

I simply think that if you don't need it, and they are not traditional (on early American guns), don't use it. Vent liners are probably the incremental first step that lead from traditional shooting to stainless steel inlines.

At least that is what I am thinking.

 

I did what this forum suggested, try a plain hole first and if unhappy with it install a liner. When I built my jaeger I first just drilled a plain hole for the vent and ignition was seemingly slow and iffy. I went back to the workbench and installed a liner (I filed the screw slot flush with the barrel for a more authentic look) and my ignition became Much faster and Much more reliable. I had to remove the breechplug in order to relieve it a tad bit and I had to shorten the liner to keep it from protruding into the bore. As far as safety is concerned the pan covered the bottom of my liner and should prevent it from ever blowing out and killing anyone next to me. Good luck and have FUN!

 

[tg]

I don't understand the safety concerns with liners (and not with drums or nipples) if installed properly in a barrel of sufficient wall thickness, but many find a plain hole to work quite well if not to small. Some feel the trend towards liners in guns today was spawned by all the re-converted caplocks back to flint in the 20th century

 

[Claude Mathis]

Here is a previous thread that deals mostly with "ignition timing", but toward the end there's some vent liner issues.

Vent Liners, etc.