Ignition problem

[DaveP (UK)]

On Sunday I finally managed to have a go with the club Brown Bess repro. Excellent fun, but somewhat marred by a persistent misfire. The priming was flashing off nicely but the main charge refused to light. Another member who had used it recently said the only way he got it to work was to trickle powder into the vent. This did produce the desired noise and smoke, but at the cost of what seemed like an enormous delay. After the first few shots I simply couldn't hold it on aim long enough and everything went low.
I did use a vent pick to check that there was no obstruction, and I also tried using a near hole sized wire in the vent during loading to make sure that there was an open channel right into the charge, but without effect.
One thing I did notice was that the vent was sited flush with the bottom of the pan. I understand that this is not considered ideal, but is it really bad enough to prevent ignition?
If so, do you think it possible to improve things by grinding out the bottom of the pan as much as we dare? There might not be much interest in tackling a serious job like plugging and redrilling, especially as under local law, the gun might then need to be reproofed.

[Habu]

I'd first check the touch hole diameter.  It sounds like it may be a bit undersize.  You'll want to read around a bit to get different perspectives, but if it were me I'd bore it to 1/16" MINIMUM.  Then I'd go about deeping the pan just a tad, then giving it (the pan) a high-polish.  (The polish just makes it easier to wipe out between shots.)

If you do this, make sure the bottom of the pan is below the bottom of the touch hole.  If not, you'll probably get some problems with gas-cutting (and I've always harbored a secret fear of blowing a lock off the gun).

[eddillon]

Has anyone tried 8 grains of a finer granulation of powder down the barrel before pouring the main charge which has been reduced by the 8 grains of the finer granulation.  The finer may put the main charge closer to the pan flash.  I don't think that this would be a dangerous practice but others may have differing opinions.  Willing to listen.

[Ky-Flinter]

Hi Dave,

What brand of powder and granulation were you using in the main charge?  And for priming?

I agree with at least a 1/16 inch diameter touch-hole and lowering the bottom of the pan if possible.

-Ron

[Acer Saccharum]

Dave, you've probably got a 1/4 or 5/16 wall thickness. With a 1/16 touch hole, that's a looooong tunnel for flash to travel thru. Some of us have internally coned our flashholes. Or installed a 'White Lightnin' touchhole liner by Chambers. I will add I've seen original Besses with a nearly 1/8" diam touch hole.

[hammer]

Dave, what is the make?  Pedersoli?  Indian?   Does it have a touch hole liner already?
Whatever the final solution it would anyway be important to use a relatively fine grained and good quality powder in the bore and pan.   Something like Swiss No. 2.   Don't need a heavy charge.   And keep the priming a little way from the touch hole so it isn't smothered. 

 If it has a touch hole liner  (Pedersoli?) you shouldn't need to open up to 1/16th.  If a straight bored hole through the barrel wall then that can help.   Best way I found to keep one of those clean was to run a spit dampened pipe cleaner through it every couple of shots.  If you decide to install a liner you cannot do better than a White Lightening from TOW. 

  I have never been an advocate of pushing a wire right through the touch hole, just leaves a void.   If using a wire I choose one that is a smiggen smaller than the touch hole and put it in 1mm, held in place by the closed frizzen (with a leather stall over the face).   Lets air out while allowing the powder to pack behind it, close to the priming and not spill into the pan.  That said, a friend who shots a Pedersoli BB, with no mods, consistently gets palm-sized groups offhand at 50yds with Swiss No. 2 and a paperclip pushed right in.   Wouldn't do that if no liner.

And got to make sure you are getting a real shower of sparks down into the pan.  You want the priming to be ignited across the pan to get the maximum and fastest flash and heat.   So a good, sharp flint.  If you have difficulty getting the best, try Will Lord of beyond2000bc.   Lovely guy over here in the UK, finest quality and fair prices.

[Dphariss]

On Sunday I finally managed to have a go with the club Brown Bess repro. Excellent fun, but somewhat marred by a persistent misfire. The priming was flashing off nicely but the main charge refused to light. Another member who had used it recently said the only way he got it to work was to trickle powder into the vent. This did produce the desired noise and smoke, but at the cost of what seemed like an enormous delay. After the first few shots I simply couldn't hold it on aim long enough and everything went low.
I did use a vent pick to check that there was no obstruction, and I also tried using a near hole sized wire in the vent during loading to make sure that there was an open channel right into the charge, but without effect.
One thing I did notice was that the vent was sited flush with the bottom of the pan. I understand that this is not considered ideal, but is it really bad enough to prevent ignition?
If so, do you think it possible to improve things by grinding out the bottom of the pan as much as we dare? There might not be much interest in tackling a serious job like plugging and redrilling, especially as under local law, the gun might then need to be reproofed.

A plain vent needs to be .078" or .093 for reliable ignition unless the barrel wall is very thin.
The powder flame does not enter the vent. Its done by radiant heat and if the main charge does not "see" enough of the flash it will not come to ignition temp. Finer powder will produce a faster more intense heat signature in the pan and may or may not help.
The vertical placement of the vent is not important unless too HIGH.
See the pan/vent experiments at http://www.blackpowdermag.com/featured-articles/index.php

Dan

[Artificer]

From Dan's suggested link;  http://www.blackpowdermag.com/featured-articles/a-study-in-lock-timing.php

When I used my old Pedersoli Brown Bess Carbine in the 70's to compete in Northwest Trade Gun matches, I used FFFFg powder in the pan and aligned the flints as well as I knew how.  However, in the 90's, I used FFFg powder from the blank cartridge to prime the pan and never had a misfire as long as the flint was still good. (The link Dan provided explains powder granulation in the pan is not as critical as we once thought and that was proven by actual testing.)  Actually, the way reenactors sort of throw the musket to the side of our bodies when doing "Cast Off" in the loading manual, one might think it would so upset the priming charge that the muskets would be less reliable.  (Actually it does, but only if the fit of the bottom of the frizzen to the top of the pan is not that good and part of the priming charge is thrown out of the pan.)  

In the 70's, I really did not understand the importance of how much of the frizzen was scraped by the flint along the length of the frizzen.  In the 90's, I got the four JHAT books and other books to investigate any way possible to make the locks more sure fire.  The link Dan provided goes into it perhaps better than most places.  I used that information and realized many "Musket Length" flints are actually TOO LONG to use in Pedersoli and other Repro Bess locks to get a good long scrape on the frizzen.  Further, long ago I found using a 6 to 8 ounce leather wrap instead of a lead wrap for the flint worked MUCH better in my Pedersoli Lock.  Perhaps the weight of the lead wrap slowed down the speed of the strike of the flint too much, again as explained by the article Dan posted?  

So when I joined as a Private Soldier in the Major's Coy, 42nd Royal Highland Regiment in the late 90's - other old time members commented on how reliable my musket was compared to many other of their muskets.  As I became the "Unit Armourer" for our unit, I found many of the other members with the most problems had flints that were too long.  Some even paid pretty good money for LARGE original French Musket Flints that were so long they worked even more poorly than modern knapped flints from Track of the Wolf.
http://www.trackofthewolf.com/List/Item.aspx/141/1/FLINT-ENG-7.  

With the thick leather wraps, that I believe protect the flints better from the shock of hitting and scraping the frizzen, one doesn't need as long of a flint as one often does with a lead wrap.  So what I did was cut a couple of leather wraps for each musket, wet the leather to better conform to the flints and then tried different lengths until I found the one that scraped the best over the length of the frizzen.  For whatever reason, I found most of the time the English Flints worked better "Bevel Down" for most Repro Besses, but I did try them both Bevel up and Bevel Down.  I tested for flint striking length by holding the cock after pulling the trigger and SLOWLY releasing pressure on the cock so it could slowly scrape down along the frizzen.  I found the 1" Flint fit most locks the best, but one lock preferred the 1 1/8" flint.  However, one Japanese made Bess preferred the 7/8" flint to work best.  (That one stumped me for a while until I tried that smaller size.)  

After I found out what size flint worked best in each Musket, I recorded it and the leather size in my "Armourer's Book" and also gave a couple spare leather flint wraps to the member along with a paper that had this information (on leather and flint size) as well - so he or she could purchase correct sized flints if I was not around when they went to buy flints.  

Oh, I also had to refit most of the Frizzens to the Pans in our Unit's Repro Locks whether they were Pedersoli or Japanese made, so the priming powder would not be thrown out.  This included my vintage 2001 Pedersoli Bess.  (The India made guns had yet been common enough for a member of my unit to have one, so I really can't offer tips on them.)

So my suggestion would be for your "Club Musket" (as opposed to a Clubbed Musket - Grin) would be try thick leather flint wraps and different length flints to improve reliability.  

God save the King.....OOPS, sorry wrong time period...... God save the Queen!
Gus
 

[DaveP (UK)]

Apologies for posting in the wrong board - I  thought some responses might get a bit technical, hence my choice,

Thanks for the suggestions. I'm afraid there's all sorts of stuff I never got to find out - I ended up running late for dinner, and as it was my turn to cook I left in something of a rush. I will check on the make, vent size and powder for future reference.
I gather that the location of the vent isn't too disastrous, which is a great relief. Seeing as this is a certified assault weapon I couldn't just take it home for a week to tinker with, and when you consider barrel proofing requirements - well lets just say that substantial modifications to a club gun are problematic to a high degree. However, part of the reason the club holds it is to afford an enjoyable initial experience to members and to guests, so I think it need to be reliable!
Both I and the other recent user commented on how coarse the powder was. The gun is issued with a box containing charges in vials, patches and ball. The chap who looks after it for us has an original which works well for him, so I expect that the powder is whatever musket grade powder he uses himself. It was certainly coarser then anything I've seen before, but then I expected it to be. I did notice that I was unable to see any of the main charge in the vent, but then the light wasn't very good...
I think the first step has to be finer powder, possibly a duplex load but, given the type of use, a reduced charge of normal rifle grade would perhaps be better.

Dan: Thanks for the link and for explaining about the flame. I had read this before, but managed to get it turned round in my head.

[LRB]

  Your problem is the low drilled vent. The only good solution is to move it up where it belongs, or drill it out much larger. Even if drilled out your prime is going to burn like a fuse. If you don't want to move it, you could grind a sort of half cone in it a ways, making a sort of funnel to the main vent hole. That should provide decent ignition. Don't grind below the pan bottom level, or you may leak prime into your lock, which can be a problem in safety. That would also be a concern if you grind the pan deeper.

[hammer]

Dan, when you say rifle grade powder you are talking black powder and not Pyrodex RS, aren't you.   Pyrodex needs too higher a temperature to properly ignite, fine in a direct line fire such a revolver, but never in a flinter.

The original powder used by the British was very high quality fine grain from the government powder mills.   Ballistic comparisons today show even Swiss powder doesn't quite compare.   Grain size was somewhere around Swiss 3.  Rifle would be close to Swiss 2.   Best to stick with Swiss 2 in a BB for target shooting with less than full loads.

Advice re flint position in the jaws is right but the simple way I determine how far out from the jaws the flint should protrude is ....   Set the flint fully in the jaws and rest the edge on the frizzen face.   Wiggle till flush across face and tighten down.  Pull the trigger while slowly easing the flint edge down the face to the bottom.  You want the edge to get within a a couple of mm from the bottom before the frizzen springs back.  If too early, knap a bit off the back of the flint or cut a knotch out of the leather where it meets the jaw screw.  If the edge goes all the way without the snap, the flint should be brought forward a little.  The couple of mm will allow for wear of the edge during use.  Check the flint after a few shots and adjust again as necessary.   Quick and easy.  And if the lock has been made with the right relationship between the parts (lock geometry) then it is 'bevel up'.

[LRB]

  The man said his prime was "flashing nicely". He doesn't seem to have a flint or prime problem. It simply is not igniting the charge.

[Daryl]

  The man said his prime was "flashing nicely". He doesn't seem to have a flint or prime problem. It simply is not igniting the charge.

yes - Acer and Dan have it covered.