Flint vs Percussion Lock Tests

[Larry Pletcher]

Larry,
Is it possible? After your tests are completed for you to run a series with the touchhole drilled out one number size at a time?
Then for the next test start with a fresh WL and using the same components and previous results as your baseline test the MV changes with each size Touch hole?
This should give us the complete package.
I for one, want a little larger TH for faster ignition and reliability and am willing to sacrifice some MV to get it. I would just like to see all the numbers because the results might influence my thinking a little.

The test you suggest is possible and for the most part has already been done.   The results you are looking for can be gotten from combining a number of tests I did starting with a MB article in 2005.  In that test I timed cylinder vents from smaller that 1/16" to over .080" .  In more recent tests we timed vent starting with .055" and went to over .090".  Not all of these were Chambers liners, but it isn't difficult to draw conclusions based on these tests.

Besides what I learned from these tests, I also would give much credit to folks on this forum - Jim Chambers  to single just one out.

Based on testing and evidence from Jim and others I would suggest looking at three areas: accuracy, velocity loss, and ignition speed and consisitency.  Decisions based on each of these factors  require compromise.
 
1. Shooters who require extreeeeme accuracy dislike vents larger than 1/16".  I was given this information from at least 2 sources.  The most recent was Jim Chambers, who related than a veteran chunk shooter replaces vents when they exceed 1/16".  This was based on group sizes. 

2. Larger vents cause a loss in velocities.  You mention this as compromise you have already considered.  My untested opinion is that in rifle calibers this becomes a major issue above .070".   I do not think vents larger than .070" are needed to get reliable ignition.  In fact  reliablity IMHO comes with careful maintaining to the lock and vent. More on this in number 3.

3. In previous testing speed and consistency did not necessarily require large vents.  The speed at which fire travels through the vent only favored large vents when repeated shots caused fouling.   A large vent is an advantage when fouling is not addressed.  When fouling is addressed, large vents loose much of their advantage.  When we meticulously cleaned between shots, small and large vents were quite comparible.

There are some things that affect ignition speeds more than vent diameters IMHO.  I call this the Bonfire Theory - The closer you stand to a bonfire, the hotter you become.  Priming powder needs to be placed as close as possible to the vent.  Obviously powder needs to be placed where sparks will land, but in tests we conducted, priming placed against the barrel - even covering the vent - was 15-20% faster than banking the powder away from the vent.  We have numbers to back this up.

So to summarize,  if I have a clean .064 vent primed as close to the vent as possible I will be faster than an .080" vent  with priming banked away from the vent.  Remember cleanliness with a small vent is next to godliness - so why a .064" hole?  I can use a pipe cleaner.  I can't get a pipe cleaner in a 1/16" vent; at .064 or .067 I can.

If accuracy is uppermost, use a small vent and keep it meticulously clean.  If you want less hassle with cleaning, and don't mind an accuracy or velocity loss, go larger.  However a vent larger than 070" gives no advantage to go with the disadvantages that accompany it IMHO.  Proper care to the lock and flint edge, and clean vents contribute more speed than big vents.

I'm sorry for the long post.  I'll remind some of a writer on another list than writes books when a simple answer will do.  This is based on tests located at www.blackpowdermag.com and on what other learned shooters have taught me.   I welcome thoughts from others.

Regards,
Pletch

[Dphariss]

Larry,
Is it possible? After your tests are completed for you to run a series with the touchhole drilled out one number size at a time?
Then for the next test start with a fresh WL and using the same components and previous results as your baseline test the MV changes with each size Touch hole?
This should give us the complete package.
I for one, want a little larger TH for faster ignition and reliability and am willing to sacrifice some MV to get it. I would just like to see all the numbers because the results might influence my thinking a little.

The WL or similar does not need a larger vent to be fast or reliable if everything is done properly. They are very reliable if the length of the actual vent is kept short. For example 1/16 vent that is too long (1/16 is too much 3/32 is much worse) is going to cause problems. If the vent is .020" long or even less, it will have no reliability problems since the powder is within .020 of the pan at the most. With powder right at the pan and a short vent to a chamber with powder in it the vent is very sure fire. The only time my WL type liner misses fire is if it gets clogged with a flake of fouling from inside the barrel/chamber in the breech. Even this is extremely rare. The lock on this rifle has a "vent wiper" on the pan that prevents any buildup on the outside of the vent.
If there was a speed increase it would likely be offset by loss of accuracy with the larger vent.
Some flint shotguns were set up to self prime when the charge was rammed, these require a larger vent.
Its really not a good idea unless the lock is equipped with a safety of some sort.
 Dan

Dan

[Darkhorse]

So here's another stupid question; Will someone explain in detail exactly how to consistantly get a .020 vent length when installing a White Lightning liner?
I for one haven't figured out how to go back in and drill just a "scotch" more from that radiused inside hole to get my perfect .020 vent length.
I have installed quite a few so I'm seriously asking this question.

Seems like I'm being lectured here like a school kid and I'm much too old to be lectured at about elementary processes. Been in this ML game way too many years for that. Guess next time I take a quick shot at a buck with a clean rifle I'll try to remember to bank my powder against the vent and hope for the best.
I was only asking for data in general that one could use to better one's own problems according to the conditions and situations one finds himself in.

[Larry Pletcher]

So here's another stupid question; Will someone explain in detail exactly how to consistantly get a .020 vent length when installing a White Lightning liner?
I for one haven't figured out how to go back in and drill just a "scotch" more from that radiused inside hole to get my perfect .020 vent length.
I have installed quite a few so I'm seriously asking this question.

Seems like I'm being lectured here like a school kid and I'm much too old to be lectured at about elementary processes. Been in this ML game way too many years for that. Guess next time I take a quick shot at a buck with a clean rifle I'll try to remember to bank my powder against the vent and hope for the best.
I was only asking for data in general that one could use to better one's own problems according to the conditions and situations one finds himself in.

Darkhorse,
Let me start with an apology.  It is never my intention to lecture anyone.  I consider myself as a student of the flintlock, and my desire is to learn everything I can about flintlocks.   I have much to learn and appreciate this forum more than any other I read.   I never meant to lecture.

Regarding the installation of WL liners, I follow Jim's directions.  I don't get the web exactly the same each time.  The last liner I put in was in the barrel stub I used for the Pan Vent Experiments.  I just measured the liner web at .054.  However this liner has an exterior cone done with a countersink.  Taking the cone into consideration, the web is probably half that. 

I have a couple of WL liners that still are attached to the plug as Jim sends them out.  I used my new depth gage from davec2.  (This worked because the wire is 1/16" and won't enter the actual vent hole.)   Once the gage was set for the interior of the cavity,  the wire would reach to the countersink on the outside.  So it appears that the depth of the countersink determines the web.  (I'm no machinist, so I probably didn't explain this well.  Maybe someone else can help here.)   I hope a machinist steps in at this point.

Regards,
Pletch

[Daryl]

Darkhorse - good questions - mine also and excellent response from Larry.  I don't see a problem & I know Larry well enough to see he wasn't lecturing.  I think perhaps I have that tendency myself, though.  Perhaps a personality trait - long winded, too - as Larry pointed out.

[Dphariss]

So here's another stupid question; Will someone explain in detail exactly how to consistantly get a .020 vent length when installing a White Lightning liner?
I for one haven't figured out how to go back in and drill just a "scotch" more from that radiused inside hole to get my perfect .020 vent length.
I have installed quite a few so I'm seriously asking this question.

Seems like I'm being lectured here like a school kid and I'm much too old to be lectured at about elementary processes. Been in this ML game way too many years for that. Guess next time I take a quick shot at a buck with a clean rifle I'll try to remember to bank my powder against the vent and hope for the best.
I was only asking for data in general that one could use to better one's own problems according to the conditions and situations one finds himself in.

If you ask a question you get an answer. The person that asks the question becomes the student in a sense in many cases. Its difficult to convey a "setting around the table with coffee or beer" atmosphere when posting on a web site. People tend to just post the facts as they see them and this can be seen as "too abrupt" etc etc. Its the nature of the way the typed conversation is carried out. There is no body language etc to help get the meaning and attitude across. Most people really have no idea who they are responding to in many cases either. One has to look at the information in the text not into what the posters attitude is.

Back to how.
Basically you measure the thing.
If the inner cone is .300 long from the end of the threads you install the liner .320 deep.
However....
.020" is a guide.
A lot of the gunsmithing of this type I tend to "play by ear" I have a +- dimension and so long as its in this range I could care less what it is exactly. In a vent liner if I were trying for .020 and I got something between .015 and .030 I would use it.

Dan

[Darkhorse]

My original post was not a question to be answered at all, hence my feeling of being lectured. I was simply asking if it was possible for another variable to be entered into your series of tests. I very much appreciate what you are doing Larry and yours are the only type tests that hold any merit for me whatsoever.
I am fully aware of the vent length variable here and knowing this, and that a lot of builders/home installers end up with less than the perfect web thickness I was asking for this data for those situations.
I was a machinist. In the last 40 years I have went from a Tool & Die maker to designing and building holding, manufacturing and alignment fixtures for the Air Force. The early years were spent with a major bus builder as a T&D maker. Now I sit behind a desk if front of a computer but still blueprints always litter my work area.
I once made all my own liners and there was no problem in getting the desired web thickness. Then I read about the WL and decided to try them. That's when I discovered the web thickness doesn't just fall into place automatically and while just touching the hole with the countersink has given good results in subsequent rifles and installations it still is not precise enough for me.
I realize now the next installation will require detailed planning to achieve my desired results. Just measuing the cone will not be enough to get the job done. There is much more to it than that. Perhaps I have been approaching things from the wrong direction.
Anyway, for the time being I'll stick to what works for me. No matter where the powder is in the pan I know my guns will go off faster than I can sense and the ball will hit where it's aimed even if the quarry is moving through the bush and a quick shot is required.
But just for thought, and maybe this has been covered before. What if the pan was full to the point of not being able to bank one way or the other?
Would this be the best of things or the worst of things?
Range work would tell but not as good as one of Larry's tests.

[Larry Pletcher]

But just for thought, and maybe this has been covered before. What if the pan was full to the point of not being able to bank one way or the other?
Would this be the best of things or the worst of things?
Range work would tell but not as good as one of Larry's tests.

I think we should test that.  Most of the time we use smaller amounts, but that could be an old wives tale too.  How about filling a pan level full and weighing the amount.  Test with that amount and again with half that much by weight?  Say a level pan weighs 3 gr.  We test with 3gr and 1.5 gr.  I'm open to suggestion here. 

Regards,
Pletch

[Daryl]

 I'm pretty sloppy when filling the pan - either full, 1/2 full or just a layer on the bottom - ignition seems to be about the same with any amount I use. I'm sure Larry's testing will or may show a difference, but when I absolutely want the pan to ignite the main charge, I feel the strongest, highest heat generated in the pan will come through with good ignition. Works for me.  The only time I get a flash in the pan without main charge ignition, is when a spec of fouling blocks the vent & this generally happens only with the .40 using 2F powder. With 3F, this doens't happen. I usually check the vent to see powder there. If it's a solid grey or black without granulation visible, it's a speck of fouling and the vent needs to be pricked.  I have perhaps a .010" to .015" channel to the main charge and the charge is visible at the vent after loading.  I don't mind changing vents more often due to burnout, but they still last a winter & summer's shooting.  Went through 19 pounds of powder from last fall untill now.

[northmn]

Personally I feel the tests show why the mule ear was never that popular of lock.  I would suggest the same may be true for an underhammer also.  I agree  that you can state that the differences are really between two different locks, but in a way it indicates popular systems may have remained popular due to the fact that there were no real advantages to any others.  Mule ears were said to require too much wood removal for installation.  One builder I knew swore up and down that a drum and nipple was about as fast of ignition as one could get.  As to flint locks, there are the English type with rollers and stirrups on the tumblers and then there are the older types.  You could do more testing than you may want to.

DP

[Larry Pletcher]

. . . . .snip . . . .  The only time I get a flash in the pan without main charge ignition, is when a spec of fouling blocks the vent & this generally happens only with the .40 using 2F powder. With 3F, this doens't happen. I usually check the vent to see powder there. If it's a solid grey or black without granulation visible, it's a speck of fouling and the vent needs to be pricked.  I have perhaps a .010" to .015" channel to the main charge and the charge is visible at the vent after loading. 

Daryl,
Your point about fouling is well taken.  In one of our tests recently we photographed fouling taken out of a liner when cleaning up:


I pushed this cylinder of fouling out of a straight cylinder hole with a small drill bit.  The effective diameter of the vent was obviously reduced a bunch.  Below is another pic of the same fouling:


I thought it sure is a good thing to use a coned liner, but we also photgraphed this when carefully removing a coned liner:



It seems nothing is immune to fouling.  These pics were a major part of my decision to use a vent diameter large enough for a pipe cleaner.  (I don't think I posted these pics before.  If I did my apologies.)

Regards,
Pletch

[Larry Pletcher]

Personally I feel the tests show why the mule ear was never that popular of lock.  I would suggest the same may be true for an underhammer also.  I agree  that you can state that the differences are really between two different locks, but in a way it indicates popular systems may have remained popular due to the fact that there were no real advantages to any others.  Mule ears were said to require too much wood removal for installation.  One builder I knew swore up and down that a drum and nipple was about as fast of ignition as one could get.  As to flint locks, there are the English type with rollers and stirrups on the tumblers and then there are the older types.  You could do more testing than you may want to.

DP

Good point.  To make a general statement by testing a single lock of each type is jumping to a conclusion instead of drawing one.  The scope of our testing, in this case, is limited by the lock mortice.  We can test any lock that fits a small Siler mortice.  We will be retesting the small Siler flint  and an intensely modified flint later in the summer. Our time is getting away from us.  We thought we'd have the flints done before Friendship, but we won't get to it until late June, I expect.  The modified Siler has many of the bells and whistles you mentioned above.

[Brian]

Great stuff Larry.  Most interesting and informative.  Thank you.

[Dphariss]

. . . . .snip . . . .  The only time I get a flash in the pan without main charge ignition, is when a spec of fouling blocks the vent & this generally happens only with the .40 using 2F powder. With 3F, this doens't happen. I usually check the vent to see powder there. If it's a solid grey or black without granulation visible, it's a speck of fouling and the vent needs to be pricked.  I have perhaps a .010" to .015" channel to the main charge and the charge is visible at the vent after loading. 

Daryl,
Your point about fouling is well taken.  In one of our tests recently we photographed fouling taken out of a liner when cleaning up:


I pushed this cylinder of fouling out of a straight cylinder hole with a small drill bit.  The effective diameter of the vent was obviously reduced a bunch.  Below is another pic of the same fouling:


I thought it sure is a good thing to use a coned liner, but we also photgraphed this when carefully removing a coned liner:



It seems nothing is immune to fouling.  These pics were a major part of my decision to use a vent diameter large enough for a pipe cleaner.  (I don't think I posted these pics before.  If I did my apologies.)

Regards,
Pletch

I have never seen this occur when actually shooting a rifle (but then I have not shot them all...). If the vent was always lined like this it would indicate little gas escape from the vent.
You would have to test the same vent with 30-60 grains of powder in a rifle or pistol shooting projectiles to draw a firm conclusion.

Dan

[Daryl]

It appears wiping the bore might not remove as much fouling form the breech area as once thought & what's there might be dampened by wiping.  I wonder how much fouling accumulates in the recess of a cap-lock with patent breech, drum and nipple arrangement, or a Knock breech for that matter?
Interesting pictures, Dan - thanks for posting them - twice.

[T*O*F]

I wonder how much fouling accumulates in the recess of a cap-lock with patent breech

Lots!!!!  I use LVL for patch lube and don't wipe between shots.  I just patch clean after a 25 shot match.  About every third match, I have to remove the barrel and soak it.  Then run my scraper brush down into the flash channel.  Otherwise it will plug solid so I can't even get a pipe cleaner or welding tip wire thru the nipple channel.

[northmn]

I had a patent breech that quit shooting for me at a match once.  It was a Hawken that I borrowed for my first shoot.  The only thing that would get that one shooting was a total flush out. The drum and nipple can be kept going a little longer in a shoot.  The new breeches have clean out screws for a reason.

DP

[Daryl]

Most of us always flush clean our barrels after shooting as a normal clean-up.  that means removing the barrel for cleaning - flint or percussion.  At Hefley Rendezvous, I still clean that way, but for a few days, I may merely plug the vent and fill the bore with cold water, let it sit for 15 min, pull the plug out of the vent and let it out the vent, then repeat the soaking and patch clean afterwards.  Putting a patch on the rod and forcing the water out the vent at high speed would be better.  The lock is removed of course and cleaned normally w/toothbrush and cold water. Both are flushing with WD40 and dried.  Guns work well after this with no ignition problems and there doesn't seem to be a buildup.

That plug of fouling in Dan's pictures along with the almost covered over 'cup' also concerns me, although in a day's shooting of up to 80 shots, the powder still comes to the vent hole with my whitelightening vents, either 2F or 3F.

[Larry Pletcher]

That plug of fouling in Dan's pictures along with the almost covered over 'cup' also concerns me, although in a day's shooting of up to 80 shots, the powder still comes to the vent hole with my whitelightening vents, either 2F or 3F.

Daryl,
I don't want Dan to take the blame for the photos.  The pics are mine; they came from the breech comparison testing.  The vent pictured with the "tube" of fouling was one of Dan's.  He added the holes so that we could change vents with a spanner wrench.  For the type of testing we did, replacing vents with a spanner was a SWEET solution.  Thanks, Dan.

The fouling came from a string of 15 firings with nothing done between shots. 

Regards,
Pletch

[Daryl]

Thanks Larry -
  "The fouling came from a string of 15 firings with nothing done between shots."

Which is the way we shoot. 

[T*O*F]

Thanks Larry -
  "The fouling came from a string of 15 firings with nothing done between shots."

Which is the way we shoot. 

Not necessarily.  I don't think Larry loading any projectiles during his testing.  Thus he didn't have the back pressure which would normally blow a lot of fouling back out of the touch hole.  I'm sure you've all fired a blank and know how fast the fouling builds up in the barrel.

[Larry Pletcher]

Thanks Larry -
  "The fouling came from a string of 15 firings with nothing done between shots."

Which is the way we shoot. 

Not necessarily.  I don't think Larry loading any projectiles during his testing.  Thus he didn't have the back pressure which would normally blow a lot of fouling back out of the touch hole.  I'm sure you've all fired a blank and know how fast the fouling builds up in the barrel.

TOF,
We did have a projectile of sorts.  We loaded a sabot over the charge with two purposes in mind.  We wanted to hold the charge in place, and we wanted  at least some resistance.  (Keep in mind here that we were working inside.)  In the trials where we did ZERO cleaning, we noticed the following:
1 The report became increasingly louder.
2 The pressure required to load  increased.
3 The impact on the bullet stop was increased.

By the time the 15 shots were finished there was a noticable difference from shot 1 to shot 15.  (This is all human observation - not a measured  result.)

Regards,
Pletch

[northmn]

Wanted to bring this topic to forefront for reference to Flint vs Percussion accuracy.

DP