.520 or .526 RB in .54

This in turn brings up another question...I doubt if any one back in the 1800's in the fur trade ran around with a micrometer..so anyone know what material was used?

I have two percussion guns from the 1850's-1860's which have original patches in the patch boxes. The .54 cal plains rifle has a patch that measures .009 in. thick and is made of cloth similiar to that in an inexpensive short sleeved shirt. The other is a .31 cal and the patch measures .014 and is made of very coarse, loosely woven cloth.

 

[GregC]

Bill...You can really thumbstart your balls in all your TC rifles using the combo you have made public?

I use the .490 RB in .50 Cal Hawken with the TC .018 patch. I don't have to pound it in but can't thumbstart it either.

I Use .530s in my .54 cal Renegades and the same .018 patch. Same thing. Cant thumbstart but don't have to pound in either.

I have good accuracy too.

 

[roundball]

Bill...You can really thumbstart your balls in all your TC rifles using the combo you have made public?

I use the .490 RB in .50 Cal Hawken with the TC .018 patch. I don't have to pound it in but can't thumbstart it either.

I Use .530s in my .54 cal Renegades and the same .018 patch. Same thing. Cant thumbstart but don't have to pound in either.
I have good accuracy too.

Actually the main point of my post was about good accuracy even with balls that can be thumb started...at the range on Saturday mornings I just use .015" patches with light 50grn target loads for playing around, and can thumb start them easily....but in spite of that, I get excellent accuracy, the point being that the lead ball doesn't have to be so tight it gets rifling marks pressed into it to be accurate.

Most of my barrels are harder to thumb start with .018" pillow ticking but it can be done...the .58cal is the tightest...the 45's are the easiest...using .440's in my .45cal's, they thumb start very easy even with .018" pillow ticking...

 

[Flint1]

Ok, I'm not real good with calipers, but I measured my Colerain .54 swamped barrel the other night. Bore diameter (land to land) is about .535. Groove to grrove (trying to measure from the bottom center of one groove to the bottom center of the opposite groove, since they are round bottomed) is about .568. What are your thoughts on possibly using a .520 RB with .020 patch in this?
Thanks.

 

[roundball]

Ok, I'm not real good with calipers, but I measured my Colerain .54 swamped barrel the other night. Bore diameter (land to land) is about .535. Groove to grrove (trying to measure from the bottom center of one groove to the bottom center of the opposite groove, since they are round bottomed) is about .568. What are your thoughts on possibly using a .520 RB with .020 patch in this?
Thanks.

I'm not an authority on this...so let's work through the numbers.

The depth of grooves is a nice to know measurement...deep ones seem to have benefits of holding more fouling and gather more excess patch material, etc.

But to the question of the fit of patch / ball combinations...with the ball riding on the lands like a train on tracks, you only have .015" windage to take up between a .520" ball and a .535" land to land diameter...that's only .0075" on each side of the ball...so it seems a tightly compressed .015" patch would make a good firm grip on the ball.

And...that would be .015" on both sides of the ball for a total .030" material being compressed into only .015" windage area...even a .010" patch would probably do, given your measurements, but I personally don't like thin patches unless a wad is used as a firewall...so unless I've miscalculated all this, if it was me, I'd try a .015" for a good tight fit.

 

[roundball]

HERE'S SOME REFERENCE INFO:
I just miced my TC .54cal flinter as follows: Land to land is .540", groove to groove is .560".

I use .530 Hornady balls and:
.015" patches for target loads (easy to start);
.018" pillow ticking patches for hunting loads (harder to start);

 

[Flint1]

Thanks for the reply. But sholdn't we be concerned with the windage along the grooves? If my groove to groove diameter is .568, and I use a .520 ball with a .020 patch, that would be a patch and ball thickness of .560--.008 less than the groove to groove diameter. Is not this what we should be concerned with sealing?

 

[roundball]

No...the ball and patch ride on top of the lands like a train rides on tracks...the land to land dimension is what you consider when thinking about the size of a ball & patch combination.

My 1:48" TC barrels have shallow .006" grooves, and the 1:66" round ball barrels have .010" grooves...I use the same patch/ball combo in them...because the land to land diameter is the same for a TC .45cal/1:48" barrel as it is for a TC .45cal/1:66" round ball barrel.

Every round ball I've recovered from deer or jugs of water at the range have had no land / grooves marks on them...surface is as smooth as when I took them out of the box.

 

[Flint1]

Thanks Roundball. What you say makes sense. One would expect the bore diameter of a .54 to be about .540. Of course the bore diameter is the land to land diameter, since the rifling grooves are cut into the bore--so what you say does make sense. The confusion arose from the fact that the groove to groove diameter is greater than the land to land diameter, thus causing me to believe the groove to groove diameter is what should be sealed. Thanks for the clarification.