Slugged the Barrel

[swedepie]

on my .50 cal TCA flinter and It came out .50 bore and lands .57 -.58, depending how hard you squeeze the vernier cal. Does this seem correct? What are your thoughts on Putting JB bore paste on the slug and using it to Lap barrel? Thanks Mac.

 

[MSW]

before you go to the trouble and expense of slugging the barrel, i'd run at least a few hundred shots through it and then start looking at the patches to see if they're being cut. slugging is dangerously close to work, and that's time you could otherwise spend launching lead.

just one guy's opinion...

make good smoke

 

[Birddog6]

I think it is a total waste of time. It is not a HP rifle & you are not going to be shooting groups of 1/4" at 300 yards. Shoot the rifle, break it in, by the time you get that done you will know it's quirks & issues & have them remedied.

And don't look for problem before they happen, as they may never happen.

Go have some fun with it. :wink:

:thumbsup:

 

[swedepie]

No expense involved. Just pounded a chunk of pure lead in the end of barrel. Was just trying to get a jump on the thickness of patches etc. This is a used rifle with some rust issues. Shoots fine, I was just wondering if lapping it with JB would help clean it up some? Mac.

 

[CoyoteJoe]

If you're hoping to lap out rust pits it will take something much more aggressive than JB. I'd start with about 220 grit lapping compound. To do any serious lapping you must remove the breech plug so that you can work the full length of the bore and spend a full weekend on it to make any noticeable difference.
I think you must be misreading your calipers. For a T/C barrel .500" bore sounds about right but I would expect your groove measurement will be more like .510", I can't imagine how you'd get ".57-.58".

 

[swedepie]

Thanks CJ, I am not the best at measuring so will double check it. Just wondering what other TC .50 were. Don't want to tear the whole barrel down to do the lap thing cause it ain't broke. I will just shoot it and enjoy. Thanks for all of your replies. Mac.

 

[Birddog6]

Scotchbrite pad cut in about 1" to 1.25" squares or circles, Ballistol or WD-40 & a jag 1 size under the caliber. (If it is a 50 cal use a .45 jag)

Keep the pad wet & start stroking full length strokes & it will remove the rust. (It will Not remove the damage from the rust, nothing will except recutting the bore. But the scotchbrite will usually take the rust itself out))

JB Bore Paste might take out some very minor etching, but I am talking about so minor, like from a mirror surface to a frosted surface ? Very Minor. It is a polishing paste, not a cutting paste. I definitely would not use lapping compound in it, as you could very easily ruin the barrel with it.

Clean it out with the Scotchbrite & then go shoot it & have fun !!

:thumbsup:

 

[Dphar]

on my .50 cal TCA flinter and It came out .50 bore and lands .57 -.58, depending how hard you squeeze the vernier cal. Does this seem correct? What are your thoughts on Putting JB bore paste on the slug and using it to Lap barrel? Thanks Mac.

The grooves are going to be .010-.020 deep in all likelyhood.
.500 + .040 (.020 grooves) should give .540 across the grooves. If you have .030" deep grooves then you will get .560" or some such.

But a caliper is not the best choice for this work. They are marginally accurate in most cases. You need a micrometer for the casting and a .500 plug gage and perhap a few more +-.500 if you really need to know these will give you a good idea of bore size.
This said I do not remember slugging a RB barrel to check its dimensions, uniformity maybe. I try 490 and 495 balls in a 50 with a thick patch .012 to .020+ and use what works best.

Dan

 

[Tom Compton]

TC barrels were button rifled in the 70s - may have changed.

If memory serves button rifling is no more than .006" deep.

Cut rifling is usually .010" to .015".
TC