Do you use a lube when you slug a barrel?

[Warpspasm]

I want to slug the barrel of my King Cobra, but I've never done it before. Do you put lube on the slug before you tap it through? Do you lube the barrel?

 

[Half-cocked]

I have only ever slugged one bore, I used a fishing weight (the egg-shaped kind) and red wheel bearing grease, driven with a hardwood dowel.

I just cleaned the bore first, then packed a little grease in ahead of the slug.

 

[wgttgw]

I am assuming you are slugging the barrel in preparation of shooting cast bullets. If that is the case my thought may go against some. I slug revolver throats and size bullets to that diameter. My thought process is the throats will size the bullets to there size regardless. If the throats are as large or larger than the bores groove diameter you will be perfect. If the throat are smaller than bore an it does cause leading than the throats would need to be opened, which I would not do to that gun. If the throats are large you need to seal the throat with the bullet to stop the leading at the cylinder throat.

Many use wood dowel for slugging, but for me it would only be done with a brass rod. There are many bad stories of wooden dowels expanding in the slug and breaking off and damaging guns.

 

[j8064]

I've slugged a number of rifle bores with lead fishing weights and hardwood dowels. Never used lube although a little bullet lube prob'ly wouldn't hurt a thing.

http://www.mdshooters.com/showthread.php?t=116866

 

[DoctorBob]

My thoughts agree with the last post (wtggtw ). If indeed you mean to slug
the barrel, bear in mind you will size the bullet to the smallest diameter in
the barrel. That dimension could be anywhere in your barrel, hopefully it
is at the muzzle, as a few ten thousandths choke is helpful in maximizing
accuracy. A few "tenths" is a big deal in prone/benchrest smallbore rifle
accuracy, however it is not as big a deal in pistol shooting with cast bullets.
As for lube, I apply "Imperial Sizing Die Wax" to the bore to get a good
slip fit on the bullet as it is pushed down the barrel. Catch the bullet in a rag
when it comes out of the bore and measure with a micrometer at several
points to see what the actual OD of the bullet is. Dr. Bob

 

[Warpspasm]

I am assuming you are slugging the barrel in preparation of shooting cast bullets. If that is the case my thought may go against some. I slug revolver throats and size bullets to that diameter.

I agree with that, but how do you slug the barrel throat? The throats in the cylinder seem fine. A cast bullet will easily pass through without them sizing down. But, I think there may be a problem with a constriction where the barrel fits the frame. I say this because the leading I get it right there at the forcing cone/barrel throat.

 

[DoctorBob]

To a great degree the forcing cone having the lead plating you describe is
in part due to the fact that the bullets pass thru the cylinder with no resistance.
If you have a .359 cylinder and the bullets leave that cylinder at .358 diameter,
then the hot gas blow-by will result in the lead depositing on the forcing cone/frame
areas as you note. A bullet that leaves the cylinder with a tight gas seal behind it
is the objective. In short , you need bigger OD bullets to give a proper gas seal,
which helps velocity and accuracy. Cylinder plating will also decrease. Dr. Bob

 

[wgttgw]

I agree with that, but how do you slug the barrel throat? The throats in the cylinder seem fine. A cast bullet will easily pass through without them sizing down. But, I think there may be a problem with a constriction where the barrel fits the frame. I say this because the leading I get it right there at the forcing cone/barrel throat.

To slug the throat you can drive a soft lead weight through the cylinder. If you lucky your as cast diameter will be large enough to be used to push though the throat and then measure the bullet. You have to size all of the cylinder throats and use the largest size. In most cases there will not be much difference in them.

Your bullet sounds too small if it passes the cylinder throat with out any resistance. How much resistance or sizing down accomplished by the cylinder throat are up for debate. Many like the bullet to be .001 to .002 over the largest of the cylinder throats. I like just a small amount of force required to push the sized bullet through the largest of the cylinder throats. If I have multiple guns of the same caliber I try to size to the largest throat of all the revolvers of that caliber.

The barrel does not have a throat but the forcing cone is directly ahead of the cylinder and leads to the barrel. If that is the location of the leading and if I am reading your post correctly and the sized bullets fall though the cylinder then a larger bullet would be my guess to solve your leading.

If not too small a rough forcing cone or too large of a gap between the throat and forcing cone would be my only other guesses. But the colt is know to be a good cast shooter.

 

[Warpspasm]

Sorry for the confusion, when I said the bullet will easily pass through the cylinder throat. I didn't actually mean they'll just drop through. If I put a bullet in the cylinder it will drop to the throat and stop, then I can easily push it through the rest of the way with slight pressure from a q-tip or something.

 

[wgttgw]

Are your bullets commerical or are you casting them?
If commecial you might try tumble lubing over the commercial lube which IMO
is too hard.
If casting your own I wold try shooting some as cast to see if it reduced leading.
Changing to a softer alloy or pushing your current one harder may help by expanding
the bullet to seal the hot gas that causes leading.

 

[Sundancer]

You can use lube but I heard if you get the barrel in the mood first....sorry the title just begged for some lowbrow humor...

 

[Bolts Rock]

You're measuring to three decimal places and if you're doing it right with a tool that measures to four decimal places (micrometer not caliper) so you want to introduce something that will have a film thickness somewhere in the three decimal place range? Let that sink in a minute.

There is no reason to use lube with a pure lead slug in a steel barrel or revolver cylinder.

 

[Warpspasm]

You're measuring to three decimal places and if you're doing it right with a tool that measures to four decimal places (micrometer not caliper) so you want to introduce something that will have a film thickness somewhere in the three decimal place range? Let that sink in a minute.

There is no reason to use lube with a pure lead slug in a steel barrel or revolver cylinder.

Hmmm... that makes sense to me.

 

[John from MD]

Hi, retired gunsmith speaking

DON'T slug your barrel the traditional way by beating a lead slug through it. This is no good for your gun.

By some Cerrosafe compound from Brownells and use it to take a casting of your bore. Cerrosafe melts at a low temp and can be poured into the barrel and tapped out after it hardens.

This process only takes a few minutes and gives better results than beating a lead slug down the barrel. You can learn all you want about Cerrosafe on the Brownells web site. They may even have a video of how it is done.

Regards,

John