Ferguson rifle - Round ball size choice?

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Licespray

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Hey guys,

I’ve got a rifle partially made up from years back that I’m looking to try and have finished. But I need to order the round ball mould. It’s rifled and the bore diameter is .797. It’s not a muzzleloader although it is a flintlock. Has a chamber cut so don’t need to worry about tightness ramming it down from the muzzle end. Should I aim for a .799-.800 pure lead ball?

According to the website this is the suggestions:


Shrinkage
The next thing to consider is the shrinkage. You can use this simple formula to calculate the cavity diameter: Multiply the ball diameter with 1.005 to get the size of the cavity. This is based on Wheel Weight alloy with 0.5% shrinkage. For absolutely pure lead you may increase the factor to 1.007 (0.7%).
These two factors should give you everything to calculate the size mould you need.
Here is an example:
.688″ x 1.007 (pure lead shrinkage rate) = 0.692816 So, in this instance you would select a .692″ mould
If using a .015″ thou patch:
.692″ – .015″ (patch thickness) = .677″ Mould”

So, do I go for 0.7% or 0.5% shrinkage? Wheel weights are easy enough to come by, or at least they used to be..
What would you do?

It’s a Ferguson action, although the maker wasn’t able to get a 10 start thread on his lathe so it’s a 4 start instead, just takes a couple extra rotations of the trigger guard instead of a single one.
Chambers cut for 160gr of 2F black powder and a .800 ball should weigh around 770gr.

Also considering what sites to attach.
For front I’m thinking:

https://thegunworks.com/shop/custom...ont-sights/blade-front-sight-german-silver-2/

For rear a couple options:

https://thegunworks.com/shop/custom-gun-building-parts/sights/rear-sights/rear-sight-folding-leaf/

Or adjustable?

https://thegunworks.com/shop/custom...s/rear-sights/rear-sight-flat-top-adjustable/

Cheers,
Troy.
 

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Would there be a civil war weapons forum where you could ask this question? Maybe the guys here don't know CW carbines.
 
Would there be a civil war weapons forum where you could ask this question? Maybe the guys here don't know CW carbines.

The Ferguson was a Revolutionary War breach loader, developed by a British Army officer.

I would use a ball that measured groove diameter.

The barrel wall thickness looks kinda thin for a 160 grain charge.
 
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