Which vent liner is best?

[nessy357]

If you go with number drills, there are 3 sizes between 1/16" and 5/64" .

Here is a link to drill size chart, for reference.


  http://www.csgnetwork.com/drillsizeconvert.html

Cheers Bob.

[tg]

There is also an eggbeater looking tool found in europe that was used to cone from the open breech if I recall corrfectly.

[mark davidson]

Thanks to all for the excellent information. Sounds like at least some form of coneing on the inside is a good thing.  A coned liner is a pretty simple improvement it seems. Drilling the hole out a little bigger is an easy operation as well. Thanks again.

[rollingb]

I use Ampco liners in my flinters, and I drill'em out to 5/64 as soon as I install them.

Fast ignition and no complaints so far.

[Uncle Russ]

I use Ampco liners in my flinters, and I drill'em out to 5/64 as soon as I install them.

Fast ignition and no complaints so far.

Personally, I think this is the way to go. It is not only economical, but you can use a countersink and "cone" as much as you like....even on both sides, if that is what you feel is best.

Uncle Russ...

[mark davidson]

Is there any theoretical "downside" to drilling out the hole to 5/64?  Why do they not already come that way and coned as well?

[mark davidson]

Also, are you guys drilling the liner out while it is in your rifle or are you taking it out and putting it in a drill press or what?  Can you just drill it out right there while it is in the gun with a basic hand drill and a 5/64 bit?

[Uncle Russ]

Mark, You need a drill press, and a drill vise....a small vice that bolts to your drill plate.

This ain't Rocket Science......far from it!
But you do need to do this as neat and "professional" as possible, because you want to be able to take it back out, and prevent marring and "chatter" if possible....a good clean cut/drill will prevent build-up.

You can do this!

Now why we do it all the time and the manufacturers don't, is anyone's best guess. I do it because it works better.

However, if you noticed in post awhile back, I said I had a Muzzleloader that has no vent liner, I have had this gun for close to 40 years and ignition has gotten better over time...why do you think this is?
I think it's because the flash hole has eroded over time and become larger..on both sides of the barrel.

Uncle Russ...

[BEAVERMAN]

Mark, other factors in flint performance come into play also, check the link here and do some reading lots of info on rock lock performance

http://www.blackpowdermag.com/featured- ... /index.php

[tg]

"Is there any theoretical "downside" to drilling out the hole to 5/64? Why do they not already come that way and coned as well?"

There has ben a lot od experimentation that shows 1/16 is the optimum size for limiting loss of pressure thru the vent and a bunch of other rocket science stuff, more and more folks are going back to a 5/64 hole or a size smaller and a bit of conning in or out with no liner and finding it works well,  the liners are even being opened up a bit past what is "best" this is a situation that what works out best on paper can be improved upon in real life, one needs to slowly open up the hole and see how thins go the powder charge may need uped a bit, it is pretty much a matter of whether one wants the fastest possible ignition or use the technology and methods that worked for over two hundred years
 Let's see, what would Mr. Knight and mr. Bridges do?

[mark davidson]

Russ, Thanks for the walk through. I can actually get access to a good milling machine so I can chuck up the liner or the whole gun and make sure it is straight and get a good clean hole. It sounds like an error on the side of bigger might be better than a more conservative approach. I'll try 5/64 and see how that does. Losing a few feet per second is no big deal and a willing tradeoff for faster ignition and more reliable ignition. I bet folks experimented with these same things two hundred years ago so I can see nothing "non-traditional" about drilling a bigger hole. :-)

[tg]

Just add a bit more powder if you think you are loosing to much umph thru the vent.

[jbullard1]

Mark
I don't think you need to error "On the large side " very much
1/16" = 4/64"
Not doubting your abilities but if you go over 5/64 you have a self pan priming situation with ffg.
I got a serious wakeup call at our last shoot from a fellow that had a larger than 5/64" vent hole and I was 8 paces away

[mark davidson]

Jerry, Thanks for the caution. I assure you that I am not going to get drill happy. I just read above somewhere that there were three sizes between "standard" and the upper limit of 5/64. Therefore, I meant that I would likely just start at the max with 5/64 since the concensus seemed to be that a little bigger was better than a little smaller.

[Captchee]

TG is correct . A vint hole is not just a hole . There are actual cherries that  are used  to cone out the hole from the inside of the barrel  so as to only leave minimal wall thickness between the main charge and the  pan .
  One of the reasons Manton used a liner was that  over time  this wall thickness burns away and you get a flash hole that’s to large . The liner material was more resistant to gas cutting  and thus lasted longer .

As to why they don’t come this way .
 Well  here are a few
1) flash hole placement can very
2)  type of flash hole .  EI do you want a liner or don’t you
3) liability . This is a very big one .  And is the reason many barrel companies no long  sell barrels that are breeched  and drilled . Basically when you  buy a barrel,  even though its called a rifle barrel , it’s a non functioning item  until you  set the breech plug and drill it for the liner or  bolster  . when you do that , you just released the company from a very large % of liability .

 Myself I only offer a drilled and cherried flash hole  IF requested . Other then that I install liners in all my rifles  I offer . I use the smallest liner I can get  IE  thread size ¼ -28 .
 The reason for that is that  over time  if a person needs to replace the liner  and they damage the threads ,  the hole can then be re tapped for a larger liner . Now of course this size depends on the rifle  but , you get the point ..

Also something to keep in mind is that the higher the charge  and heavier the bullet , the more resistance is  caused and thus the  higher the pressure forced out of the flash hole . Thus creating  greater gas cutting / wear  to the thin  face wall of the liner ..
 Like Russ though I do like the Ampco liners . Jims , white lighting may be just a tad faster  but  personally I cant see any real difference. They do fit alittle tighter do to being able to   grip the liner better , but past that  I see no real overwhelming differences