75 cal. conical

[wild_willie_10]

I have a 75 cal muzzleloader with a rifled barrel. This gun has a 1 in 72 twist. I asked the gunsmith who made the gun about shooting a conical. He said because of the large diameter and the particular twist, it would probably shoot a conical with very good accuracy. He also said I probably out of luck finding a ready made conical for that size of bore. I'm currently shooting a .735 round ball with a lubed .015 patch. Because of a family function he was traveling to and would be away for 10 days, I didn't think of one important question to ask him. It was "what should be outside diameter of the conical be". I found a company that would make the mould for me, if could come up with outside dimension. I'm looking at a hollow base type of conical. With all that be stated, does anyone know what the o.d. of this conical be? All help would be helpful.

Willie

Happy Thanksgiving to All.. and remember what we all have to be thankful for...

 

[paulvallandigham]

Normally, you would want to size a ball or conical no more than .010" under bore diameter. However, you want to be cognizant of the Groove diameter of the barrel, too, and not just the diameter across the lands. You might want to reduce that diameter on a conical to .005 under bore( land to land) diameter if you have deep grooves to fill.

That is a very slow rate of twist for shooting any conical, but a short bodied conical may shoot okay. The length of the conical is important, as it is in all bullets, in determining the proper rate of twist for a given caliber of gun, to use to fire that particular bullet.

If I were you, I would use inside calipers to measure the groove diameter, and then the bore diameter. I would work on finding a RB load that would shoot well. That round ball is going to weigh in at 1 1/8 oz. of lead, which is a hefty chunk to be pushing out the muzzle. That is 492 grains! YOu are definitely going to know the gun goes off. The conical will weigh more. After you work up that RB load, then, attend some matches with other shooters with such guns, talk to them, and get their recommendation. Then talk to the mold maker about what he recommends. The diameter of the conical is going to depend on whether you intend to shoot the conical bare, or use paper to patch it, or use cloth patching, or use an Oever powder card wad to seal the gases behind the conical. Is the conical going to be flat based, or have a hollow cavity inside like a minie ball? All these things are going to have to be considered in deciding on what size mold to use in a Rlfe of .75 caliber.

A round ball out of a .75 cal. rifle is going to be a huge ball spinning down range, and will be effective at killing deer, elk, moose, caribou, and brown bear at least to 100yds, and probably much further. I don't really see the advantage of shooting a conical of that size in a hand held rifle. The open sights are going to limit the range at which you can shoot the gun effectively. And, with that limitation, the Round ball would be more than adequate.

 

[RedFeather]

You might be able to use one of the 835 grain conicals mentioned here for use in the .72 Kodiak double rifle. I guess they could be paper-patched up. Maybe even a 12 guage slug? What kind of stock/butt does this pea shooter have?

 

[arquebus]

You mentioned that you wanted a hollow-base conical[url] mould.....in[/url] other words a Minie design. I'm fairly certain that your rifle (going by the twist) would be designed for such a projectile. As to size, you will get best results with a Minie if it is no more than .002" under BORE size. You will need to take some measurements; using a lead slug is the easiest way I've found. I usually drive an oversize roundball into the muzzle, remove it & then measure the bore & groove diameters with a caliper. However, being a .70 caliber, it may be hard to find an oversize ball! One tip I've read here on the forum is to use one of the tapered fishing sinkers if you can lay your hands on one. Another thing, very few moulds will cast a truly round bullet, so I normally buy a slightly oversize (.002"-.005") mould & then size the bullets down to the required size. The sizing dies can be as simple as a cylindrical die that you push the bullet through (nose first) with a dowell in a drill press. Rapine makes this type of die (& a little press to use them with) but if you have access to a lathe they are quite simple to make. By the way if your mould maker is willing to make a Minie Mould to your specifications I'd appreciate it if you could let us know their name & contact number, as custom Minie Moulds aren't easy to find.

 

[lapetit]

Here is a couple of options for 75 cal conicals.
First try[url] www.underhammers.com[/url], he has conicals from 28 cal to 4 gauge {1.050"}, sells them by the pound and uses the Post Office one price box for shipping. One pound or twenty pounds it's the same shipping. I wouldn't be surprised if he had several styles and weights.
Second, find a 69 cal mould and someone with a lathe and a four jaw chuck. Center up the mould from the bottom side and cut the bands to what ever size you want. I have done this several times with 58 cal to make 20 gauge slugs and also 69 cal for 12 gauge and ten gauge. The twelve gauge was for a Kodiak 72 cal double rifle which we eventually got to shoot 6" groups, two from each barrel, using a single, center mounted sight.
Third, take a .715 or .725 ball mould, chuck it up in the four jaw and open it up to full diameter. I have heard these called ball-ets. Paper patch or use your normal cloth patch material with lube. I made one of these for a 58 cal underhammer. With a 5 grain increase in the powder charge they shot to the same point-of-aim as the roundball, with equal accuracy. This method gives you a 25% increase in bullet weight.
Drop me a line if you need more ideas.
Lapetit

 

[Sharp Shooter]

If that is close to a 12ga you could buy some 12ga slugs for reloading shotguns and see how that works.