Ferguson rifle - Round ball size choice?

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.

Anyone?

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

reddogge said:

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

Click to expand...

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.

I have no experience whatsoever with the Ferguson, but I sure would love to. BTW: your work bench is nice although a little too clean.

Hi,
I shoot a Ferguson a lot and have built 3. All mine are the historically correct caliber 0.65". I have no idea how your rifling will work compared with mine but I have no need to use a ball the same size as the bore. I have used several combinations. A 0.648" ball worked fine but did not allow much powder behind it in the chamber.. I settled on 0.626" balls and these shoot very accurately out to 100 yards (the furthest I've used it) and I can get a bit more powder behind it. The original guns were meant to shoot 0.615" ball which was standard British carbine ammunition. I have very poor accuracy using that sized ball. I have no idea why anyone would build a Ferguson action in 0.80" caliber. I hope he did a good job on the threads of the screw plug so they seal and can take that a 160 grain load or you are going to get a face blast of hot air. Even with the historically accurate TRS action I get a little puff on my face. FYI, the originals used 0.615" balls and about 70 grains of double strength superfine powder similar to our Swiss 3F. I suspect you are going to have real fouling problems because of the blast and using 2F powder.

dave

I shoot mine with 615 diameter balls. its been pretty accurate. If one uses a groove diameter ball accuracy goes away on account of the ball growing these neat little Sputnick satellite wings. I have thought about going to a .620 ball just to see how it would handle it.