Counterboring A Barrel To Save Its Length?

[Bruce Cobb 1723V]

Has anybody done this instead of crowning and lopping off the end of a worn barrel? If so, how big a diameter was it over the size of the bore? How deep? I'm sure I am not the only one who has thought of it. Thanks

[Maillemaker]

My first thought that comes to mind is that as the bullet clears the rifled portion of the barrel and enters the counterbored area the charge gasses will escape around the bullet, possibly altering its flight characteristics.

Steve

[johnefelts]

I believe Steve is correct.

[mb3]

I dont know how well a counter bored BP rifle would work. If counter boring is the same as a re crown then I have owned and shot a couple of modern rifles that were counter bored. They shot just fine- re crowned.

[matt]

Steve,
If what you are saying is true than none of the TC rifles with the QLA system should shoot worth a darn. The question is when the barrel is counterbored is the boring done straight? If it is then you have basically recrowned the barrel internally cause the lands should all be even at their end, the small amount of barrel that was counter bored should have no effect as when the bullet leaves the rifling it is flying as true as it is ever going to get. A damaged crown lets more gas escape from one side then the other. This is not the case is a properly counter bore barrel.
matt

[Maillemaker]

I have never heard of the TC QLA system until now. I just did some googling on it and I am not entirely sure what it is they are doing.

Steve

[Rich Foster]

Bill Large did this to some of his new barrels. Mine is .54 Miss. 8 land 8 groove 1/2" in depth taper inside muzzle outside of lands to make it load easier and it shoots second to none like all his barrels. Of course Bill large did things to his barrels that others said could not be done and he did it and made it work. He was one of the best barrel makers. Now that saying that counter boring is possible but whoever does it better be good at it. Because if it is not true you will get flyers. Rich Foster DSR TW4765

[MR. GADGET]

Not our type but I own several military guns that were done that way, if done correct, should shoot fine.
Also own a TC Encore 50 cal, they have always CB their barrels about 5/8 - 3/4" for ease of loading hunting loads. No real need for a starter. Makes it fast, easy and it shoot fine.

[Southron Sr.]

At one time I had an original M1861 Rifle-Musket that had been counterbored-IT SHOT FINE

[rachbobo]

The 1819 Hall Rifle is a rifled breechloading flintlock. The first few inches of the muzzle was counter bored.
This was done to make muzzle loading easier if the "tip up "action froze up from rapid fire.

Bill Cheek
Cockade Rifles

[Jim Leinicke 7368V]

Years ago I bought an Enfield with an ugly dent in an otherwise excellent bore, just a bit inside the muzzle. I had it lightly counterbored, just enough to cleanly wipe out the dent and rifling. The thing shot just fine and as far as I know still shoots fine.
Jim

[Bruce Cobb 1723V]

So it works great, maybe we can save some worn out muzzles by counterboring. Now we don't have to worry about taking off more than the .50 barrel length in our rules. I think that even going .06 or more over bore dia is better than trying to just remove enough rifling. Then you don't have to worry so much about boring true to the bore and have the bullet get pushed to one side..

[Bob Elka, 12001]

I think the fact that it works in a T/C firing a saboted round kept relatively clean shot to shot isn't a good comparison to the average skirmish situation.
If you have a damaged muzzle and simply wish to extend the usable life of a barrel and no longer have the 1/2" extra metal available for a proper
re-crown than go for it. However if you are a serious competitor looking for the utmost in your equipment you're only kidding yourself. With subsequent
shots lube and fouling will collect at the bottom of the counterbore and create an uneven release of gasses at the base of the bullet creating a questionable
situation. NOTHING performs as well as a proper crown. There again each situation and what is expected from the rifle may vary........ As for the T/C
the counterbore is there for a reason. It certainly aids in loading but it helps to shed the sabot from the bullet more uniformly enhancing accuracy.......

[MR. GADGET]

I think the fact that it works in a T/C firing a saboted round kept relatively clean shot to shot isn't a good comparison to the average skirmish situation.
If you have a damaged muzzle and simply wish to extend the usable life of a barrel and no longer have the 1/2" extra metal available for a proper
re-crown than go for it. However if you are a serious competitor looking for the utmost in your equipment you're only kidding yourself. With subsequent
shots lube and fouling will collect at the bottom of the counterbore and create an uneven release of gasses at the base of the bullet creating a questionable
situation. NOTHING performs as well as a proper crown. There again each situation and what is expected from the rifle may vary........ As for the T/C
the counterbore is there for a reason. It certainly aids in loading but it helps to shed the sabot from the bullet more uniformly enhancing accuracy.......

Not sure about the sabot as I'm not using them much ever.
I have loaded lead in it for years. Several different molds and box bullets.
Also the normal Goex.
Shooting the RCBS Bullet Mold 520 Hodgdon North-South Skirmish in it now, just a lot of sizing.
http://www.midwayusa.com/product/568575/rcbs-1-cavity-bullet-mold-520-hodgdon-north-south-skirmish-520-diameter-adjustable-grain

As far as the military guns that I have, some are one 1/8" others are as deep as 1/2" or more.
I could see if you try to cut a deep counterbore but something in the range of a deep crown or 1/8" I don't see it building up too much junk.

If you have a ding in the crown, it would be a start, other then that you would need to drop $$ for a liner or barrel to keep the barrel length in spec.

[hp gregory]

there are rumors that mr brockmiller shot a smith carbine that had several inches of counter bore to it. seems he did very well with it.but im sure this would be looked on as a last resort repair to a damaged barrel.

hp

[Pat in Virginia]

The Kerr rifle used by the CSA in Tennessee as a snipers arm was chamfered as were other English arms of the period. I think the idea was to make precision loading easier in the field where a bullet starter was not practical.

Pat in Virginia

[bobanderson]

With subsequent shots lube and fouling will collect at the bottom of the counterbore and create an uneven release of gasses
at the base of the bullet creating a questionable situation. NOTHING performs as well as a proper crown. There again each situation and what is expected from
the rifle may vary...

Wouldn't that depend on the way you counterbore? If you only cut deep enough that you are removing the lands that were worn or damaged and you left
a counterbored area that matched the groove diameter of the rest of the barrel, there would be no area to collect fouling. I've never seen it but I bet it would shoot just fine.