A question on boolit design

[Matt85]

What happens when a boolit is slightly wider than it is long? Will this cause problems?

I ask because I'm trying to design a cast boolit to more closely match the POI of a ball. My rifle was originally regulated to fire a ball over black powder in a cartridge. I have since developed a smokeless load firing a conical, but the conical is longer/heavier leading to a higher POI. I would like to develop a smokeless load using a smaller/lighter conical to duplicate the balls performance.

My thoughts are to shave 0.1" off the nose of this design:
https://www.accuratemolds.com/bullet...bullet=85-1050

What are your thoughts? Thank you

[Nobade]

You may end up with something like the big lube bullets that were popular for cowboy action shooting. They work fine out to moderate ranges but aren't very accurate as range is increased. Why not just load with a ball as the rifle is intended?

[Matt85]

You may end up with something like the big lube bullets that were popular for cowboy action shooting. They work fine out to moderate ranges but aren't very accurate as range is increased. Why not just load with a ball as the rifle is intended?

This isn't exactly a long-range gun. I'd say 75 yards is close to what I'd consider its max range.

I've never had much luck firing balls out of cartridges. On top of that, my source for bullet molds is better than my source of ball molds (I won't get specific but take my word for it).

[pmer]

I haven't been done this road but I wonder if you could take a bigger round ball and size it down and tumble lube it?

[cwtebay]

What rifle / chambering are you working with?
If it's merely a POI shift with a standard profile bullet - would it be simpler to adjust your sights?

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[mehavey]

You considering/using a 0.85" diameter bullet ?

1. What are you shooting this thing out of?

[fredj338]

It would be like a stubby wadcutter, accurate in close but unstable as distance increases.

[Matt85]

What rifle / chambering are you working with?
If it's merely a POI shift with a standard profile bullet - would it be simpler to adjust your sights?

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You considering/using a 0.85" diameter bullet ?

1. What are you shooting this thing out of?

My gun is a W.J. Jeffery 8-bore double rifle. The gun uses a 3.25" strait case and has 0.847" bores. Original load was 10 drams (273gr) of black powder under a ball. The sights are not adjustable and I would not be willing to make permanent modifications.

It would be like a stubby wadcutter, accurate in close but unstable as distance increases.

Do you think it would still be stable to 75 yards? I would like to use this load for target and medium game.

[cwtebay]

I appreciate your situation, I wouldn't be crazy about modifications either. Perhaps a try before you buy solution is for you. Milling off your proposed length progressively from your current mould's bullets should help you figure out what will and won't hit your desired POI. Generally, Jeffery was quite good at supplying load data for comical and ball loads.
What is your rifling rate?

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[lar45]

Great question, what is the rifling twist rate?
We need pics of your rifle.
I like your idea or shortening the pictured mold.
You'll have to look at the twist rate to see how stable it should be.
I would think that it should be stable to 75 yds if the twist rate is close enough.

I recently help a guy with his Grandpa's old 40-60 Winchester rifle. The twist rate was like 1:40", so it needed a very light short bullet. I cast up a sample of everything I could find and we tried stepping down until it was happy. We ended up with a 175gn 40S&W TC powder coated to make the the diameter of the rifle's groove size.

[mehavey]

That (Accurate) bullet going a measly 1500fps would be stable at all of a 1:90 twist rate.
I don't think the OP has anything to worry about there.

In fact that ACC 85-1050 looks to be an outstanding initial entry point.
Try it. Adjust POI by adjusting load.

[Matt85]

Not sure on rate of twist, will have to figure that out with a cleaning rod. I believe it to actually have a fairly fast twist though.

My current load is this mold (link below, made to 0.85") over 67gr of Blue Dot, which yields around 1350fps. I haven't done extensive testing but so far this seems to regulate well, albeit about 4.5" high.
https://www.accuratemolds.com/bullet...bullet=84-1200

Adjust POI by adjusting load.

This doesn't work with double rifles. Increasing or decreasing the speed will bring the two POI's closer together or further apart. As far as I know the only way to raise and lower the POI without effecting regulation, is to increase/decrease the projectile weight.

[mehavey]

Your twist rate (whatever it is) will handle a .85 x .75 conical at 1,350fps

NOTE: 0.75 is a rough calculation of the shortening of that Accurate 85-1050 to pull it down to 900grains/
But ask Tom Ellis for the actual mods/alloy first.

[Matt85]

Your twist rate (whatever it is) will handle a .85 x .75 conical at 1,350fps

NOTE: 0.75 is a rough calculation of the shortening of that Accurate 85-1050 to pull it down to 900grains/
But ask Tom Ellis for the actual mods/alloy first.

Thank you

I think I will put in an order for the mold with the nose reduced by 0.1". I wanted to check with guys here because I'm a novice when it comes to designing bullets.

This 8-bore has been a great deal of fun, but also a very serious challenge. Loading data and general knowledge about the cartridge is very limited. The man I would have loved to consult with, was my friend Mr. Pappas who sadly passed away somewhat recently. He taught me to love these old bore rifles, but my lack of funds prevented me from getting one until it was too late to have him help me.

[Chill Wills]

Something like this Lyman 45 cal button bullet scaled up might be a starting point.
Go to this address and look up this number for the image.

http://ps-2.kev009.com/ohland/Cast_B....html#308_mold

"457130. This bullet is same weight as the round ball. Is preferred by some for light work on account of having groove for lubrication and two bands to hold on to the rifling. (PB, 144 TP is 130)"

[mehavey]

I will put in an order for the mold with the nose reduced by 0.1".

Email Tom Ellis first and tell him you need the 85-1050 design fore-shorted to match the 85-caliber ball weight normally used in that 8-bore.

On that ball weight: What was the alloy used when the barrels were regulated?
That drives the weight.

[Digital Dan]

Simple path? Round ball sized to accept a thin patch, maybe .005" thick without significant compression. Use a foam plug to keep your powder where it belongs.

On topic of round balls in a cartridge, I've never had an adverse issue with that. I shoot a .357 case necked to .30 caliber and it does quite well with bullets AND round balls. Very slight flare in the case mouth, ball sized to .309 is gently inserted and the flare removed w/o a crimp. It shoots the balls near one ragged hole at 25 yards and 1,440 fps. Critters hate that load.

https://i.imgur.com/Sftn5LR.jpg

[Matt85]

Email Tom Ellis first and tell him you need the 85-1050 design fore-shorted to match the 85-caliber ball weight normally used in that 8-bore.

On that ball weight: What was the alloy used when the barrels were regulated?
That drives the weight.

I couldn't tell you, it's not in the ledger. The limited information in the ledger is that it was a ball over 10 drams. The date on the ledger is 21/10/95, so I doubt any more information is available from other sources.

[mehavey]

Since rifled, and at that (rather massive) ball weights/diameter/rotational inertia, consider Lyman #2.
OOC: is there any lube or grease cookie in the original loading?

[Messy bear]

Not sure this would help but if you want to try something that isn’t permanent, have the base band machined off some of your bullets you cast now. Maybe learn wether or not something that short is workable. Just modify the bullets you have already. Allows you to try different weights just by how much you take off the base of your bullets. I do this all the time with something longer than what i am hoping to design