Barrel Coneing revisited

Last night I got a call from LC Rice concerning my .40 barrel. While I had him on the phone I asked him his opinion on barrel coning. He said he didn't have an opinion on coning as he had never had a coned barrel, but he thought the way it was coned had everything to do with the end results.
But to get to the point of this post: Mr. Rice said he has donated a coneing tool and barrel to a couple of writers who are going to do a definitive test. Including shooting before coneing to establish a baseline. Then after coning with the tool. Then cutting off a couple of inches of barrel and reconeing in a 4 jawed chuck in a lathe. It should be 5 or so months before this article is published (Muzzle Blasts). He suggested I wait until all these tests were complete and I had read the results before I actually coned a barrel.
Good advice.
This is just the kind of test I have been looking for.

The only problem I see in that is the cutting off the barrel part. When you do that you changed more than one condition of the bore, not just the coned & non-coned condition, so the test will be inconclusive......
When you cut off the barrel you changed the resistance of the bore.
Maybe that is being too picky, but just a thought to consider.

:m2c:

From what I gathered they may be trying to determine if a machine cut cone is better or no different than a hand tool cut cone. After they decide what effect the coneing itself has on accuracy/Muzzle Velocity, or whatever criteria they are using.
Probably the only way to do it right is use 2 barrels and establish a baseline for each, then cone using the 2 different methods.

Mr. Rice said he has donated a coneing tool and barrel to a couple of writers who are going to do a definitive test. Including shooting before coneing to establish a baseline.

Click to expand...

Many people have already done this, myself included. There was no discernible loss in accuracy, but loading is much easier.

Greetings All,

To begin with......after spendind 1-1/2 hours last night two finger typing my thoughts on coning and then losing it, my comments wiil be a continuation of short postings.

For me the main and only question is will the accuracy level of a coned rifle muzzle equal the accuracy of a barrel crowned in todays traditional manner?

Over the years, I have drastically improved the grouping accuracy of many, many muzzleloading, centerfire, and rimfire rifles by simply recrowning the muzzle so that it is an exact 90 degrees square to the BORE. This is mandatory before any other crown work is done.

I am so distrustful of ALL factory crowns that re-crowning is automatically done before any other accuracy checks are completed.

With that said, it is my opinion that if a barrel cone is properly centered and aligned with the bore, then theorically, there should be no lose in accuracy, and should be equal to a conventially crowned muzzle.

It is also my opinion that the only way a cone or conventional crown can be accurately cut, ground, or lapped in place is to use a metal turning lathe. Using a lathe with standard and time tested machining centering procedures is the only method that results in pre-determined and repeatable predictable processes. Without this repeatable reliability, a machining standard or base line cannot be established to determine an accuracy shooting base line and subsequient accuracy shooting test.

Now, I know that the use of modern machining tools will immediately fly square into the face of those who insist on using ONLY "the old timer's way. If it was good enough for them, it is good enough for me".

I will not argue with that philosophy, except to say, do not use that argument with me if you are using modern manufactured barrels and locks.

In the next part I will explain my thoughts about using a lathe to cone a barrel, and yes. I do think Joe Wood's tool is an excellant item for coning.

Best regards, John L. Hinnant

It is also my opinion that the only way a cone or conventional crown can be accurately cut, ground, or lapped in place is to use a metal turning lathe.

Click to expand...

I agree with you in theory, but in practice, we have coned muzzles by hand and there is no discernible loss of accuracy. With that in mind, it appears that a lath may not be necessary after all.

Some things that can be measured in the lab do not always make a perceptible difference in the "working environment".

Just an observation. eace:

Kind of related to the coning issue. I have known guys to cut an inch of off thier muzzles due to ram rod wear, etc. I am not sure that a barrel is that smart or the projectile that is fired from it. I would think coning a muzzle or even counter boring the first inch would get you back to a "square" end for the projectile to leave the barrel from.I do have an old gun here that is coned and I am looking forward to doing my modern Ml'ers.

I'm still fairly new to a lot of this custom muzzleloader stuff, but I think I know what coning is. Can someone clarify exactly what coning is for those of us that aren't sure?

::

Thanks,
Al

It's basically putting a tapered counter bore on the inside of your barrel to make it easier to start the PRB or bullet.

OK then got further question on coning. I have observed muzzles that are just counter-bored a little bigger (lathe) and no taper. Is there a difference ?

The parallel counterbore - like T/C's QLA - is only really useful for aligning conicals.

I agree with the comments earlier on crowning. If your crown is off square or damaged anything else you try for accuracy won't help much. A large radius on a crown can also function like a short cone, making it easier to thumb start the ball.

I've also seen some very nice crowning jobs done with hand tools. (Brownells carries the equipment). It just takes more time (and a bit of skill is always handy, also).