wierd iginition problem

[M. De Land]

Gus, we have the same dynamic used in some black powder cartridge loads.
Some competitors put a paper disk in the bottom of the case to keep the flash hole clear when the case is charged for more consistent ignition.
The primer flash traverses the clear flash hole before igniting the main charge.
The unimpeded flash promotes more consistency in maim charge ignition.

 

[M. De Land]

That would never have happened with a hole diameter pick in the flash channel.

 

[Flint62Smoothie]

Gus, we have the same dynamic used in some black powder cartridge loads.
Some competitors put a paper disk in the bottom of the case to keep the flash hole clear when the case is charged for more consistent ignition.
The primer flash traverses the clear flash hole before igniting the main charge.
The unimpeded flash promotes more consistency in maim charge ignition.

Not entirely the WHOLE picture of why they do that, as the prime purpose for doing so is to reduce the brisance (think firing/flash rate) of the priming compound and make it a more gently ignition of the BP charge.

Primers are made to different strengths or power, so technically “ brisance,” in these terms is defined as “the shattering effect of a high explosive”.

Another way to achieve a similar result is using large pistol primers instead of rifle primers, for cartridge loads.

 

[Tom Compton]

Thanks

 

[54ball]

Another thing too....

I set this rifle up for a liner. The vent is drilled dead center of the barrel flat. For architecture the lock was set as low as possible on the side flat. The vent is in the center of the pan but high. Actually the frizzen covers the hole.

So I do believe I may have drilled the vent a 16th too high for ideal ignition.
It shoots blanks well because the powder is somewhat loose. Even with a pretty big wad, air still escapes around the load as it is rammed down.
With a patched ball, the air tight seal compresses the powder. This air tends to escape through the vent thus crowding the power at the vent.
With the vent being a little too high, it's not getting the goody of the flash. It gets enough to shoot a loose blank.....but not enough flash time to light a compressed load or a load where the powder grains are blocking the vent.

If the vent was just a little lower it would be closer to the height or most intense part of the flash. The flash or flame takes the path of least resistance.

So I was close but no cigar in setting up the vent. Lesson learned. This may not be a problem for a liner. This may not be a problem for a rifle with a big lock.

Remedy.....right now it shoots with picking the charge or loading with a pick inserted. To get it shoot reliably without picking, I do believe I'll have to start enlarging the vent.

Bottom Line...
I drilled the vent just a little high for ideal ignition with a 16th hole and a smaller " Southern Mountain" 19th Century English styled lock.
https://flic.kr/p/21QDTSy

 

[azmntman]

Keep your eyes on Vidmate App. Surely the answer to this is coming as well.

:slap: :surrender:

 

[M. De Land]

Yes, I had forgotten the baffle effect of the paper disk as I don't load that way myself.
Ned Roberts said that less potent caps in percussion guns worked better for accuracy improvement as well, in his book.

 

[54ball]

Another session today with interesting results.
Enlarged the touch hole to 5/64.
6 shots. Condition between rains....no wind.
Shot 1
Clean rifle no picking...great ignition.
Shot 2
No picking pan flash pick...fire.
Shot 3
Picked while loading. I heard a small "Pop" as I had the ball about halfway down....no pick. It popped out to who knows where. Panflash. Panflash over prime panflash turned the rifle on it's side over primed directly over the vent turned it back...fired into the backstop to unload it.
:hmm:
Shot 4
Loaded no pick mainly because it's gone. Primed as normal except before closing the frizzen I tilt the rifle 45 desgrees to the left....settle the grains back into pan close frizzen...the rifle shot well
Shot 5
Same thing 45 degree tilt close frizzen rifle shot well.
Shot 6
Same thing tilt to the left ....weak spark....gently knap, cock and fired well.

Conclusion...
Even though it was a rather short session. The Rifle will fire reliably by simply priming it and tilting it to the left.
The frizzen problem is becoming more apparent. After 5 shots the flint was still sharp but not sharp enough to get a good spark. This rifle right now requires a new or freshly knapped flint to spark well. Just after a few shots, the spark is weak.

First I'm going to temper the frizzen to see if that helps the sparking. If not I'll try to harden and temper it. As crazy as it sounds, in my experience, a weak sparker for whatever reason can have an effect on ignition even if it lights (flashes the pan).

Another thing, with the touch hole being 5/64 I feel that some powder (3 F) should have came out the touch hole when loading. None did. If ignition problems continue I may pull the breech and check for burs.

 

[Flint62Smoothie]

Another thing, with the touch hole being 5/64 I feel that some powder (3 F) should have came out the touch hole when loading. None did.

FWIW I only get some to dribble out for 1, maybe 2-shots, but only on a clean barrel.

 

[Tom Compton]

Another thing, with the touch hole being 5/64 I feel that some powder (3 F) should have came out the touch hole when loading. None did.

FWIW I only get some to dribble out for 1, maybe 2-shots, but only on a clean barrel.

Sounds like the flash channel/ante chamber is still not completely clear. Of course complete cleaning won’t help produce sparks.

 

[Herb]

Forget the old forum reader's tale of tipping the prime away from the flash hole. If I have flashes in the pan, picking the vent usually helps. But tipping the 4F prime into the flash hole insures ignition every time. I also tip 3F or 2F against the flash hole if I am using that.

 

[Grenadier1758]

As I read the posts and looked at the pictures, 54Ball is right handed and tilting the rifle to the left will bank the primer toward the touch hole. Its best to have the prime all along the bottom of the pan and banked toward the touch hole. That way any sparks will find powder.

It does sound as if there is a lock geometry issue if the flint is dull by the fourth shot. Time for the match stick under the rear edge of the flint to make it more of a scrape rather than a bash.

 

[54ball]

Thanks Herb and Grenadier.
Yes this is a right handed rifle although I shoot it off the left side.
Just a quick tilt to the left for the prime to kiss the touch hole then I turn it back right and make sure the prime is distributed throughout the pan.
This works and it allowed me to actually concentrate on accuracy.
When it starts sparking weak, that's when I'll have delayed ignition and and even some delayed pan flashes.
The lock is a Davis Common....basically a goosenecked 1803.
Locks of this period tend to be bashers. The Pedersoli 1805 Pistol locks come to mind. It's not really Pedersoli or even Davis's fault as that's a inherent design feature.

My goal is make this rifle....load, prime and go with the drilled vent. Past experiance shows that flintlocks especially drilled vent guns start off finicky but eventually become more forgiving. Hopefully this will be the case.
Also as you learn one, you chip away at problems. I'm fairly confident with the vent issue as I think I learned the secret handshake.
Now I think I'll look into the frizzen issue. I'm just not happy with a dull yellow single spark....or no sparkle at all on a pretty new flint.
New flint, it sparks well when you test but you don't' know if the 3rd shot will spark. Sometimes it will go say 10 shots maybe more....sometimes 5 maybe less before knapping. After knapping....not many shots left before I have to change flints.

I am just chipping away at it. Right now it's not Battle ready.

For the newer guys if you read this......it's all tied together like tuning a old car. It's not just the points....it's carberetor, fuel pump, spark plugs and so on. You just got to go through the punch list.

 

[Black Jaque Janaviac]

You stated that the 1st shot on a clean gun works well. As I was envisioning the differences in loading blank vs ball I could imagine the ball could force fouling into the hole.

With a blank, the path of least resistance for expanding gas will be out the muzzle, so relatively little fouling should accumulate in the touchhole. But under a ball some gas will shoot out the hole first. Then you "plunge" the bore with a bal which forces more fouling into the vent.

Try noting whether the first shot from a clean bore goes off without picking. That would indicate it has something to do with fouling build-up from previous shots.

I can't see why a piece of actual powder clogging the vent would cause a pan-flash. Slow ignition, maybe, but not consistantly flashing. The kernel of powder would certainly ignite.

 

[Brokennock]

The pick popping out under the air pressure of seating your ball reminds me of something I left out. I believe I mention I don't use a typical forged steel/iron pick for leaving in the touch hole during loading, I made one out of coat hanger wire specifically for the purpose. What I've failed to mention in the past is that, when I made it, once I had the length/taper correct so it is just barely off the opposite barrel wall when inserted, I stoned a barely perceptible flat along it and cut into this flat with a fine knife edge file. Just enough air can escape from here that I don't get the pick poppkng out, or that air pressure lock one sometimes gets when seating a truly tight projectile.

 

[54ball]

Thanks to all who have responded.

Let start by saying....

I feel very stupid.

Everything has come together. The rifle fires beautify and is very accurate. It needs picking when it needs picking and most of the time you'll know it. Simply banking the prime to the hole and then settling it back down in the pan did the trick.
I did enlarge the vent to 5/64.

Frizzen issue....

With the same flint that performed so poorly at the end of the last session, it did well after simply cleaning it. I do believe the Geometry and the location of the flint after flash and the jet from the vent dirties or fouls the striking face of the flint. My other rifles do not seem to foul the flint to this extent.

Any way a simple wipe of the flint solves this as long as it has an edge......Basic Stuff.

Sometimes as we learn these things, we look for problems that are not there.

So....
Prime management....
Vent management....
Keeping a good and most importantly clean flint...

I have learned this one. The key to reliability was so simple. Again basic stuff.

With that said.....
Have I really learned the rifle or has the rifle improved a little? :hmm:
It was somewhat finicky when I started it on blanks but became.....reliable.
On live ball it was very finicky but I learned it and it came around.

Every drilled vent rifle I have owned seemed to require an in depth period of learning and use. I do believe while learning a new rifle, it improves.

So before any work is done, I do think a new drilled vent gun needs to be shot many many times for the shooter to learn it and for the rifle to improve.

 

[Brokennock]

I'm glad you got it worked out. So much in everything we do comes down to fundamental basics. It's nice when we can be a little lax, with a forgiving flintlock, bow, or some other skill/equipment relationship, but when things aren't working right,,,,, it's back to basics.

 

[Martino23]

M.D.

I like your idea and I think I'll try it.

The way I understand it, you put the wire in the touch hole before you load the barrel with powder? Correct?

Also, what kind of wire? Would copper work? Is it soft enough?

Thanks, I am fairly new to flintlocks, and trying to learn

 

[Brokennock]

I made mine out of coat hanger wire. Should be a detailed description somewhere in the replies above.