Muzzle coning

[paulvallandigham]

Since the widest part of any bore is the Groove diameter, and a good PRB load will stuff enough fabric down into the grooves to seal gases behind the PRB, coning is only going to change how the Patch reacts as the lands begin to widen to groove diameter. Since the PRB is traveling about as fast as its going to go before it leaves the muzzle, when it enters the cone, the only change in the fabric patch will Be, IMHO, a de compression of the fabric on the lands, and slippage of the patch backwards as the lands are made smaller in the cone as the ball approaches the muzzle. This cannot break the Seal of the patch to the lands, since the gas pressure in the barrel is falling, constantly, and the fabric is still held between what remains of the lands and the lead ball until the PRB actually reaches the muzzle.

As long as the cone is centered in the bore, there should be NO loss of accuracy. The " universal coning tool" described above that is centered in the bore by using a jag and patch that screws into the nose of the cone will insure that the cone is centered, as well as doing the coning on a lathe with a boring bar.

 

[MikeC]

I have coned two of mine own using Joe Woods tool and the last .54 Roy built for me I asked the muzzle be coned. In the two I did I saw no loss in accuracy. Loading is easy. I will never own a rifle that does not have a coned muzzle. Once you go coned you'll never go back... :thumbsup:

 

[Dphar]

I have 2 issac haines and 1 jim bridger hawken an have coned all three with a joe wood tool. can not tell any diffrence except all are a pleasure to load now. no longer know what a shortstarter is.

Did you extensively target them before and then compare group sizes afterwards?
This is the only way to know, everything else is guess work.

John Baird and TK Dawson tested a rifle claimed to be from a Hawken related shop in St Louis. It was described in Baird's "Hawken Rifle".
This barrel shot very well, 50 caliber with a 48" twist the bores interior was described as follows
"...the bore is a slight taper from the breech to a point 9 1/2 inches from the muzzle. Hear a choke is apparent for about 8 inches, then from there to the muzzle a flight flaring is seen. Measuring approximately .0005", about 1/4 inch from the end of the barrel this suddenly increases another .002..."
This is far different than the current practice with often removes all the rifling at the muzzle.

Dan

 

[Dphar]

I have plans to do some testing of this. I am rebarreling a rifle is a GM and can leave it long enough to shoot with a normal crown then cone and still shorten it and use a normal crown again.
Excessive funneling has to reduce support of the ball at the muzzle. But only testing will show and it will likely take at least 100 rounds.

Dan

 

[The German]

I have myself seen guns/ barrels which do not shoot well ( and no coning of barrel). I believe some barrels just do not shoot as well as others ( or shoot quite bad) and you can not really see the difference, looking at them.

 

[LRB]

Hi Dan. I was going to try that with my new Rice barrel, but it shot so good from the get go, I decided to leave well enough alone, and I found that I really would not have enough length to re-cut a normal crown. Please let us know your findings.

 

[wattlebuster]

Yes Dan off the bench and freehand and could not tell a bit of differance except SO much more easy to load :grin:

 

[zimmerstutzen]

offhand with a coned barrel, standard crown, or smooth bore doesn't make much difference for most hunters out to 75 yds. If a coned muzzle can do MOA at 100 yds, I'd like to see it. Of course if the barrel is only capable of 5 inches at 100 yds, coning, rifled or smoothbore won't make much difference.

 

[Fauquierfarmer]

I have a 54 cal.coned Rayle barrel. It shoots very well, however it is difficult to center precut patches beneath the ball, the patches tend to slide to the side a bit when starting the ball.I often resort to a short starter to more quickly start the patched ball,while the patch is still centered.

 

[paulvallandigham]

Use larger, pre-cut patches with a coned barrel, to give you more fabric extending over the sides. Try patches made for .62 or .58 caliber guns for your .54 barrel.

Coned barrels were intended to be used with patches cut at the muzzle with a patch knife, from strips of fabric. You can use oversized patches, as mentioned above, but you can't skimp by using small, barely large enough patches sold for your .54, without a lot of contortions and effort to control the location of the patch while your other hand puts the ball into the center of it.

Suggestion: If the gun is not resting against a bench, hold the gun between your knees. That frees up both hands.

With your dominant side hand, center and hold the patch on the muzzle with your thumb and index finger, holding the edges to the muzzle on the sides. Use your weak hand to place the ball in the center of the patch, and to press it into the barrel. In pushing the ball down, the patch will slide out from under your finger and thumb, but will remain centered.

Now, wipe your hands, and fingers, off with that towel you remembered to take with you to the field or range. You did remember to take a towel with you, didn't you? :wink:

You can use cleaning patches to wipe grease off the muzzle, and off the loading rod you used. :shocked2:

I find that if shooters are prepared to deal with messy lubes and residue in and around the muzzle of their guns, when loading and cleaning, they are less likely to do all kinds of dances to load that gun! :rotf: :surrender: :hmm: :thumbsup:

Using a patch knife to trim patches at the muzzle is a FUN part of this sport. It does make you learn what a sharp knife IS, and how to put a razor's edge on a blade. But, that is a skill that will serve you well all the rest of your life. :shocked2: :haha: :idunno: :surrender: :thumbsup:

You don't have to trim those oversized, pre-cut patches I mentioned above, however. Testing has shown that the extra fabric just allows the patch to separate from the ball faster, and it does not affect accuracy. Some shooters, in fact, use short starters to push their balls Below the muzzle in the coned barrels, so that there IS extra fabric left over the top of the ball when its pushed down onto the top of the powder charge.

If you are a serious neat-nik, you can use a Ball Block, where you load a block of wood, with appropriate sized holes in it( see "Articles" at the top of the index to this forum for a chart giving hole diameters for common calibers) with your patch and ball, then use that ball block to center the ball over the bore- coned or not. That will let you load those pre-lubed patches without touching the fabric at all. Of course, there will still be grease on the ball block........

 

[Fauquierfarmer]

Thanks a bunch ! Cheers, John

 

[LRB]

Just my opinion, but I don't believe coning was intended for cutting patches at the muzzle. I think if your muzzle is that hard to center a ball and patch with, it was likely over done.

 

[BrownBear]

Just my opinion, but I don't believe coning was intended for cutting patches at the muzzle. I think if your muzzle is that hard to center a ball and patch with, it was likely over done.

I formed the same impression. I do my coning a little at a time, seating a ball every so often until I can thumb it just deep enough to suit.

On the broad topic, I relish the cones on my rifles because I'm a field shooter rather than a range shooter. They're hunting guns. If I was a match shooter where I could have lots of tools and time, I'd never do it. Recrown maybe if I had accuracy problems, but there would be just no reason to cone rather than crown.