vent liners

[walt53]

how many guns have no vent liners and how long would just a vent hole last before burning out. i'm looking at a gun that does not have a vent liner  and am wondering as it well be my FIRST flint lock rifle. look forward to your input. walt

[Hungry Horse]

It’ll last quite a while, but it won’t shoot for diddly squat, because the ignition will be slow, if at all. Most modern muzzleloaders offered without a vent liner are junk anyway. IMO, you should look for a good used gun with all the right parts, rather than a new gun with all the wrong parts.

  Hungry Horse

[Mauser06]

Hungry Horse, you forgot that many builders that don't use liners will internally cone the touch hole. 



I don't know how long it would take to enlarge it to the point of it being too big. 



You can always drill it out and put a touch hole liner in.   

[MuskratMike]

If it doesn't say "White Lightning" or similar take a pass. All mine have Mr. Chambers liners and I have no issues with any of them and I shoot a lot of rounds a month, every month, every year.

[rich pierce]

Larry Pletcher has done extensive studies of ignition times with and without vent liners. I can’t recall the numbers but many would be shocked to learn a vent liner improves consistency more than ignition time.  I think vent liners can be 20% faster. Not twice as fast as some think or indicate.  A drilled vent should be good for 2000 shots.

[bob in the woods]

My two main hunting guns , one smoothbore , one rifled do not have vents. My 10 bore has never failed me, and I've taken many bears with it, as well as deer, partridge, turkeys, ducks and geese. My standard vent size is 5/64ths .
If I need to put a liner in one day I will, but so far, over a 1000 rounds through each and it's still all good. Many people have commented on how fast these guns are when fired. I don't believe that the guns of my time period and place [1750's
Great Lakes / French Canada ]  had vent liners , so I prefer to not use them unless building a later period gun .
 

[Daryl]

5/64's appears to be about .078", which stands to reason will certainly help with ignition speed.
 Along with that, the side wall on a 10 bore would be fairly thin, making a normal hole for vent quite
 OK, as Bob has shown. Normally a vent like a WL, starts at about .055". Some guys initially drill them
out to .0625". A 1/16" vent hole in the side of an octagonal barrel will likely not give very quick ignition
except if shaped concave on the inside to make a thin all as on the liners.

[Joe S]

According to Pletecher’s published data, White Lightening vent liners are no faster than straight holes. Mean ignition times were:

Straight Hole:  0.044 seconds (N = 20)
White Lightening: 0.036 seconds (N = 60)

The apparent difference in ignition speed is not statistically significant. That means that if you were to run this test again, due to random variation alone you might find that the straight hole was faster than the White Lightening.  Even if the difference was real, very, very few humans (if any) could detect a difference of 0.008 seconds.

It seems to me that people who have inconsistent ignition with straight holes are using flash holes that are too small.

[Daryl]

It seems to me that people who have inconsistent ignition with straight holes are using flash holes that are too small.

THAT is the point I was making, Gordo.  I suspect if Plech had bored the WL liner to 1/16", it would have been faster yet and statistically so.

[Joe S]

I suspect if Plech had bored the WL liner to 1/16", it would have been faster yet and statistically so.

All of the data shown above was done with 0.062” (1/16”) flash holes. My apologies for failing to note that in my first post. I will blame it on my being insufficiently caffeinated earlier this morning.

Pletcher has tested the effect of flash hole size in vent liners.  His data are shown below. I would need the raw data to do a formal analysis, but you do not need a statistical test to see that there is no difference in ignition time for holes between 0.062”(1/16”) and 0.094”(3/32”).


Re: Touch hole liners?
« Reply #16 on: March 08, 2010, 05:28:37 PM »    
________________________________________
I tried to put together the numerical information to compare straight cylinder vent holes to vent liners.  But first, I will try to limit my thoughts to numbers only.

In the Feb. 2000 issue of MuzzleBlasts I published an article called “Touch Hole Ignition Timing.”  I timed what I thought was “too small” to “too big.”  This first hole diameter was .040”.  It was plainly too small and the test was terminated without finishing all 20 trials.  Every additional hole size was timed 20 trials and the average determined.  Below is a summary of the test results:

Diameter----------average----------------variation
.052------------------.0523-------------------.0671
.055------------------.0474-------------------.0359
.0625 (1/16)----------.044-------------------.0321
.0625 (ex.coned)------.0406------------------.0278
.070-------------------.0408------------------.0389
.078 (5/64)------------.0445-----------------.0322
.086-------------------.0418------------------.0326
.094 (3/32)------------.0436------------------.0242

[Joe S]

Rich – As far as I know, Pletcher has not done any testing directed at consistency of vent liners vs. straight holes for a series of shots. He typically cleans everything between shots, so his data are specifically relevant only to a single shot from a clean gun.

[bob in the woods]

Just to clarify, I have nothing against vent liners where appropriate .  If reliability suffered without one, my hunting gun would have one, however, it works fine as is. For those who don't like the look of stainless steel on a flintlock rifle, I believe that Jim Chambers has a White Lighting liner in carbon steel now if you ask for it.  My inside coned .62 rifle would approximate that kind of liner I would think. If and when it burns out enough to require a liner, that's what I'll use.

[David R. Pennington]

I cone touch hole from inside bore and get as good results as a liner without the ugly SS. I don’t know how long it will last. I haven’t had to re-line one yet. I guess it would depend on how much you shoot.

[Pukka Bundook]

Depending on what you are making, stainless can look quite right for a touchhole liner.
Later British and Continental arms often had platina (platinum) liners, and these look quite like stainless.
No, not right on a Longrifle, but for other and later types, quite possible.

[Joe S]

Pukka – Do you know how common interior cones were on later English guns? It seems to me that at least some would have been coned, particularly in the later guns when all the locksmiths were doing everything they could think of to improve lock speed. I know that there are extant American tools for cutting interior cones from the breech from the late 1700’s. Coning an English liner would have been even easier.

Walt53 - What kind of gun are you looking at? If it’s from India, I would be very cautious.

[Mike Brooks]

It's pretty easy to put a vent liner in a gun that doesn't have one.

[Natureboy]

  I have a Chambers' White Lightning liner in my flintlock rifle, which had terrible problems with misfires before it was installed. Ground flush with the flat it's installed in, it's hardly visible. Now, I never worry about the dreaded FITP, and you have to look very close to see the liner.

[Joe S]

It's pretty easy to put a vent liner in a gun that doesn't have one.

Agreed. However, vent liners are like tattoos. They're easy to put on, but tough to get rid of if you decide you don't want them anymore.

Mike, you probably know as much about English and continental guns as anyone else here. Have you ever encountered one with an internal cone?

[Mike Brooks]

It's pretty easy to put a vent liner in a gun that doesn't have one.

Agreed. However, vent liners are like tattoos. They're easy to put on, but tough to get rid of if you decide you don't want them anymore.

Mike, you probably know as much about English and continental guns as anyone else here. Have you ever encountered one with an internal cone?

Yes. But I have seen far more with gold or platinum liners. Seen quite a few with bushed touch holes too.

[Joe S]

Thanks Mike. I am also curious if you have seen the gold or platinum liners with an internal cone.

Grinslade's book has a picture of an early 1700's HV fowler with what appears to be a brass or gold bushing. Perhaps to rectify a burned out touch hole?

[Mike Brooks]

Thanks Mike. I am also curious if you have seen the gold or platinum liners with an internal cone.

Grinslade's book has a picture of an early 1700's HV fowler with what appears to be a brass or gold bushing. Perhaps to rectify a burned out touch hole?

I'll assume by only looking at touch hole liners from the outside that the gold liners are all coned on the inside. In fact, since they are riveted in place they will have a natural cone. Learned this from several conversations with Mark Silver.

[Joe S]

That makes sense. Very interesting. Thanks Mike.

Walt53 - So, what have you decided to do?