Drilling Vent to 5/64s

[Jckrabbit]

Hi Guys,
I recently purchased a Jackie Brown 62 Cal Fowler from Track. I am very pleased with this little gun, but the vent is 1/16 direct drilled and it has been coned on the outside. It fires very reliably, but from what I've read the outside cone is a negative not a positive. I plan to install a liner at some point, but thought I might drill it out to 5/64 in the meantime. This is my first flinter and the learning curve is steep!

Does this sound like a good idea or a waste of time???

Thanks in advance,
Jckrabbit

 

[Zonie]

IMO, increasing the vent size to 5/64 diameter should increase the speed of ignition enough that you will notice the difference.

With small bore guns like a .36 or .32 increasing the vent size can have a negative effect on shot to shot variation but on a big bore like a .62 caliber the increased loss of pressure thru the larger vent hole won't be noticed.

I say go for it. Assuming you don't break the drill bit off in the hole, you have nothing to loose and greater reliability and speed of ignition to be gained.

 

[Jckrabbit]

Thanks for the quick reply!

I'll let you know how it goes.

Jcrabbit

 

[LRB]

You said it was reliable. I would say, leave it be until you decide it isn't. If it works, why change anything?

 

[J.D.]

I am very pleased with this little gun, but the vent is 1/16 direct drilled and it has been coned on the outside. It fires very reliably, but from what I've read the outside cone is a negative not a positive. I plan to install a liner at some point,

I'm with Wick, on this one. If it's reliable, why change it. Why would a cone on the exterior be a liability? An exterior cone funnels the heat of the flash into the vent, so that's a good thing.

IMHO, if the existing TH works well for you, why complicate things with a liner. IMHO, I would wait to install a liner until the existing TH is burned out...and they will burn out, in time.

Personally, I don't know what the fascination is with a 5/64" diameter TH. That is .078, and IMHO, too big, for all but the largest bores. I much prefer a .068 or .070, which leaves room for some burn out without causing too much of an accuracy concern.

God bless

 

[tg]

I have drilled my hole to 5/64 and found the guns more reliable than with the smaller hole, but if things are working good as is I see no reason to change you will likely experience better reliability not faster speed with a larger hole from what have found,you may compromise and drill it inbetween the two sizes, some folks prefer this size to start with.I have had a small cone on the outside on some guns and it has not been a problem to my knowledge.Wick and JD probably have the best advise but if yoyu really want to experiment don't go all the way the first drilling.

 

[gordy]

I'd have to agree! if it's performing well I would leave it be . Cant see where a liner is going to help anything . :thumbsup:

 

[ohio ramrod]

If it ain't broke don't fix it! There was some testing done a few years back with high speed camera's , as well as grouping size , in muzzle blasts a few years back and they determined that a .062 (1/16 )vent hole properly coned gave the best results. So if your gun is working well I recommend you leave it as is. It will eventually burn out to 5/64 or beyound.

 

[mr.flintlock]

My advice is :If your ignition is fast and reliable-leave it alone.

I make my vent liners out of 1/4 X 28 X 1/4 stainless steel allen set screws. I drill them with 1/16" drill then cone the inside with an 82 degree counter sink to within just a few thousands of the end of the hole at the wrench recess. I place the wrench recess to the outside and flush with the outside of the barrel at the pan. When priming I rock a little prime powder into the wrench recess. It is so fast that I never hear the flint hit the frizzen. I believe that the wrench recess actually channels the fire to the main charge.

 

[ebiggs1]

I use a #50 drill, which is .070 and I like cones on both side of the touch hole. Try the #50 first and than you can go up to 5/64th if you are not pleased. But I don't have anything under 45 cal either.

 

[Jckrabbit]

I quess my noooobiiee status shines through a bit on this one. I think the advise to leave it be is probably what I'll do. Most of my problems come from inexperience at this point. I am, or at least was in my younger days,a pretty good shot with both modern hand guns and rifles. My advise to young shooters was always to buy as much ammo as you can shoot, shoot, shoot. I believe I will take my own advise.

On behalf of all noobies;thanks again for the time invested in helping us.

Jckrabbit

 

[larry wv]

You will do fine Jckrabbit . :thumbsup: Larry Wv

 

[Tumblernotch]

I had to drill the coned liner on my .40 out to 5/64ths soon after I built it to get it to shoot with reliability. It is coned on the inside. But I have to agree with the others. If it works fine like it is, don't bother. If you have some trouble down the road, then fix it.

 

[paulvallandigham]

My flintlock rifle came with a white lightning liner, with its slightly smaller than 1/16" TH. I thought it was shooting fine until one day it began to misfire. I cleaned it,and tried everything under the sun to get it to shoot properly, but every once in awhile, it misfired again.

I talked to my long time friend and gun maker, Craig Witte, who suggested opening up the TH. I went at it carefully, and slowly, working my way up the numbered drill bit chart. It took me six months of trial and drilling to arrive at the 5/64" hole size, but that has cured the gun of misfires.

Trust me, Craig and I talked many times about going that large, before I went there. He was kind enough to ask me to describe my entire loading and cleaning process, and asked questions for me to check and get back to him with the answers.

I would never tell someone to just OPEN that TH to 5/64" and forget it. The smaller the vent hole, the greater the pressure can be made in a flintlock barrel, without having to use 3Fg powder. ( I use 2Fg because it gives me faster ignition in the barrel than does 3Fg, which tends to pack down no matter what I do to prevent the packing in my flintlock.)

If you are not getting misfires with any flintlock, liner or not, "Don't Fix What Ain't Broke!" is still as good advise today as it was when a very old man told me that when I was a kid 50 years ago :hatsoff:

 

[Jckrabbit]

Thanks Paul! At the risk of opening another can of worms; how loose should the powder be? I've been packing mine (3f) down as tight as I can thinking that would be the "right" thing to do. I'm also worried about the ball not being seated on the powder and ruining my barrel. On a good note, I fired 10 rnds last night at 22 yrds. 5 into a one hole cluster, 1 slightly higher and 4 bad flinchers. I think I'm gaining on it.

Jckrabbit

 

[Tumblernotch]

I would just seat the ball firmly on the powder. If you keep ramming the ball it will crush the powder and that will have some effect on how the powder burns. And probably more importantly, crushed powder will draw moisture faster.

I've drawn loads before and have found some of the powder crushed even though I only seated the ball and didn't ram it hard. This stuff crushes very easily.