Author Topic: Conical, hollow base projectiles, accuracy and ability to cast? (Read 1719 times)

VA Rifleman · « **on:** May 13, 2010, 04:15:37 PM »

Gentlemen, Does anyone have experience using conical, hollow base projectiles (AKA Mini Balls) in larger sizes such as a 2.5 inch smoothbore? Wondering if they would have an accuracy / velocity advantage in a smoothbore cannon or could they be just a pain to cast with no real advantages? Can't recall seeing much use in the civil war except for the rifled pieces. Must have been a reason. I might be better off just shooting billard balls with patches. Thanks again for all the good info on lead vrs zinc!

RocklockI · « **Reply #1 on:** May 13, 2010, 04:41:16 PM »

Hi VA rifleman . Thats a good question and you will get opintions . I cant say anything about sizing ...?

But , I have heard and seen remarkable results with conicals from a smooth bore , nearly unvbelievable iirc .

I dont remember the details so I wont comment further .

Gary

the short little pellet like shape are called 'trashcans' waisted wasp like a .177 pellet .

Double D · « **Reply #2 on:** May 13, 2010, 06:05:45 PM »

Patching balls bigger than 3/4 inch in a cannon is asking for problems. You need windage to safely and uniformly seat the ball.

Have you considered making sabots?

subdjoe · « **Reply #3 on:** May 13, 2010, 08:42:19 PM »

Running a hollow base conical in a smooth bore like that is like putting a 450 on a kids tricycle. You can do it, but why? No spin imparted so it will act like a football thrown with no spin, or a knuckle ball, it will drift, float, wobble, curve, and do other odd things. And, because of the conical shape will go even farther off line than a round ball.

When I started reloading for my 38-55 I trusted what the company told me about the groove diameter. The bullets I bought matched the diameter of the lands. No spin. I could not keep in on a 28 x 40 sheet at 25 yards (well, out of 15, three hit the edges). I have a feeling that using a conical in a smoothbore would give similar results. On the other hand, I was able to keep a patched ball out of my 12 ga front stuffer on a head sized target at 50 yards all day.

GGaskill · « **Reply #4 on:** May 14, 2010, 08:58:36 AM »

I don't know exactly what would happen if you made a pointed Forster type slug for a cannon but the basic idea is to keep the mass in front and have a tail section that is kept to the rear by the air flow. The Forster is round nosed. My guess is that the tail would have to be longer to keep the pointed nose facing forward. But it should be possible. An attached sabot would have a similar effect.

little seacoast · « **Reply #5 on:** May 14, 2010, 12:38:36 PM »

Something like this?

Balances about 3/4" behind the top can rim, can filled with fiber reinforced mortar mix.

GGaskill · « **Reply #6 on:** May 14, 2010, 01:01:02 PM »

That should be a good starter as long as the can doesn't collapse.

VA Rifleman · « **Reply #7 on:** May 14, 2010, 01:51:20 PM »

Little seacoast, Very cool!! Solve's the casting / mold problem. Wood base? Guess they would be heavier then a standard ball thus the need to reduce the charge. How do they shoot?

VA Rifleman · « **Reply #8 on:** May 14, 2010, 02:23:14 PM »

Quote from: Double D on May 13, 2010, 06:05:45 PM

Patching balls bigger than 3/4 inch in a cannon is asking for problems. You need windage to safely and uniformly seat the ball.

Have you considered making sabots?

DD... Yup, considered sabots. Have this picture in my mind of the dreaded discarding sabot, fin stabilized round such as used in the 120 mm smoothbore in the Abrams but have no idea as to how to make them. What started this line of thinking was how the Minnie ball made such great improvements in both accuracy and range when used in the period muskets. Seemed hollow base, conical's would be easier to make then sabot rounds but I could be wrong.

Concerning you much appreciated comment on potential problems with patching balls in larger pieces.
I need to get you the actual dimensions as to the shot size for my cannon but they seem loose. Looser then the recommended 1/40 windage spec. The previous owner patched the balls with several thin layers of what looks like tissue paper. I bought the mold, but it hasn't arrived yet. If I patch only so much that the round is somewhat snug and doesn't roll out of the barrel when tipped downwards (embarrassing I would think), would that create issues?

Trying to understand here so I don't so something stupid. Sincerely appreciate your guys feedback!

dan610324 · « **Reply #9 on:** May 14, 2010, 03:03:33 PM »

wouldnt it be possible to use a sabbot that just got the 1/40 even if the ball is slightly smaller ??

little seacoast · « **Reply #10 on:** May 14, 2010, 03:15:45 PM »

VA Rifleman, The nose is a 2" Fox Industries case hardened steel ball that is press fit into a tomato paste can, bottom cut out and filled completely with mortar mix- no collapsing can here. The base is a wooden sabot cut to a slip fit in the barrel and gorilla glued on, they hold up quite well. My limited experience shooting these is that they do not tumble in flight and leave nice straight grooves when they impact on grass. Substantial recoil with 600gr of Cannon grade!

RocklockI · « **Reply #11 on:** May 14, 2010, 04:17:52 PM »

Hi VA Rifleman . we are not talking about high tech fin stablized projos . Just short pieces of wood that go between the bag and the ball they have a cup on one end to cup the ball .

If I'm misinterpeting something ,please say so ......

I make them bigger than the ball dia. so the ball never comes in contact with the bore .

I distinctly remember some photos of a fairly recent match for smooth bores full scale . The groups were very good ,it must have been one form or another or shuttlecock or foster thing going on .

The groups I recall were near clover leaf .

Gary

VA Rifleman · « **Reply #12 on:** May 14, 2010, 04:44:18 PM »

Quote from: RocklockI on May 14, 2010, 04:17:52 PM

Hi VA Rifleman . we are not talking about high tech fin stablized projos . Just short pieces of wood that go between the bag and the ball they have a cup on one end to cup the ball .

If I'm misinterpeting something ,please say so ......

I make them bigger than the ball dia. so the ball never comes in contact with the bore .

I distinctly remember some photos of a fairly recent match for smooth bores full scale . The groups were very good ,it must have been one form or another or shuttlecock or foster thing going on .

The groups I recall were near clover leaf .

Gary

Oh, Now I got you. DUHHHH... Thanks for the clarification Gary! Now I understand what Dan610324 suggested and little seacoast was demonstrating. Thanks dudes for helping this rookie. I'm a little in awe of the knowledge of the members here. Somewhat of an art to this.

Double D · « **Reply #13 on:** May 14, 2010, 05:10:51 PM »

Quote from: VA rifleman on May 14, 2010, 02:23:14 PM

Quote from: Double D on May 13, 2010, 06:05:45 PM
Patching balls bigger than 3/4 inch in a cannon is asking for problems. You need windage to safely and uniformly seat the ball.

Have you considered making sabots?

DD... Yup, considered sabots. Have this picture in my mind of the dreaded discarding sabot, fin stabilized round such as used in the 120 mm smoothbore in the Abrams but have no idea as to how to make them. What started this line of thinking was how the Minnie ball made such great improvements in both accuracy and range when used in the period muskets. Seemed hollow base, conical's would be easier to make then sabot rounds but I could be wrong.

Concerning you much appreciated comment on potential problems with patching balls in larger pieces.
I need to get you the actual dimensions as to the shot size for my cannon but they seem loose. Looser then the recommended 1/40 windage spec. The previous owner patched the balls with several thin layers of what looks like tissue paper. I bought the mold, but it hasn't arrived yet. If I patch only so much that the round is somewhat snug and doesn't roll out of the barrel when tipped downwards (embarrassing I would think), would that create issues?

Trying to understand here so I don't so something stupid. Sincerely appreciate your guys feedback!

Here's sabot's for my 1 inch gun.

We have to get your mind focused in the right direction here...think pre 1899...

Minie balls were not for smooth bore muskets, they were for rifled muskets.

Any thing you wrap around the ball can and will come loose when pushed down the bore. If you only wrap one direction how do you keep the ball from rolling off the patch as it is loaded?. Also how do you keep the patch for snagging. bunching, wadding or tearing as it goes down the bore.

Use a sabot. Here is one of several discussions we have had on sabot Gary's Sabot.

RocklockI · « **Reply #14 on:** May 14, 2010, 06:46:30 PM »

Also as far as I know the sabots of the civil war had nothing to do with accuracy ,they were only there to make sure the fuse was seated up . maybe also as a device to attatch powder bag and projo .
Gary

little seacoast · « **Reply #15 on:** May 15, 2010, 06:46:49 AM »

I just noticed GGaskill's reply with the comment that a sabot might act as a stabilizer to prevent tumbling. Can't speak for all circumstances but offer the following pics as evidence of some instability in a round ball with sabot attached (way too attached).

Double D · « **Reply #16 on:** May 15, 2010, 12:25:24 PM »

I use one drop of Elmer's glue in the bottom of my Sabot to hold it to the ball. This glue does not hold the sabot tight to the ball. Actually kind if fragile

All the sabots I have found so far have been found in front of the target, shed from the ball. I have been firing at the steel targets not paper. Hope to change that this week if the road to the range is open.

GGaskill · « **Reply #17 on:** May 15, 2010, 01:42:29 PM »

If the sabot is going to act like a tail, it needs to be longer so it can get leverage against the iron ball. I think it would have to be at least twice as long as the one shown.

RocklockI · « **Reply #18 on:** May 15, 2010, 02:30:07 PM »

and may drop the charge
down abit . IF you get them to fly true they may make up in accuracy what they lack in range .

little seacoast · « **Reply #19 on:** May 17, 2010, 05:12:40 AM »

Rocklock and Gaskill, I'll make up a few wooden sabots about 3 times the length and try those. Will post pics when finished. Be way easier than the current can projectile to make.l

Double D · « **Reply #20 on:** May 17, 2010, 06:12:41 AM »

Doubt your sabot need to be that long. I would start incrementally. Make 5 sabot of 1 caliber length, 5 of 1 1/2 caliber, 5 of 2 caliber.

I would also think it would be better if the ball was seated deeper in the sabot. I'm no aerodynamics engineer, in fact I don't even know how to drive a train, but it just seem to my eye that air flow around the ball is going to catch on the flats of the front of the sabot and disrupt everything.

VA Rifleman · « **Reply #21 on:** May 18, 2010, 03:04:23 PM »

My concern with the short wood sabots is the short contact area with the bore. Would seem to create a "tipping moment" as the wood is the windage control but all the weight is in front. I can't see Double D's pic. Must have something wrong in my browser settings. I've a pic of a modified little seacoast design but havn't masterminded posting pics. Anyway, my present shot is 2.175" in dia in a small can that's measures 2.425" in dia by 2.5" in length. (Optimum windage = 2.437"). The shot is recessed in the can almost all the way so it balances close to the middle and the full length of the can acts as a bearing surface in the bore. The bottom and sides are potted with little seacoasts fiber impregnated mortar. Just trying to "use what I have" as far as shot. Thinking desirable attributes for sabots that allow reduced dia projectiles would be.
1. Repeatable bore alignment for the projectile.
2. Light in weight.
3. Ability to transfer charge pressure from the sabot to the projectile.
4. Repeatable sabot / projectile downrange separation.

Double D · « **Reply #22 on:** May 18, 2010, 03:22:55 PM »

Here is a better angle angle on one of my sabots.

Using the sabot with the cast lead balls worked pretty good last at the Montana cannon shoot. I was able to knock down the metal cannon silhouettes quite regularly with them.

I'm not sure how the steel ball will work, they are lighter.

VA rifleman you say you can't see my pictures. What are you seeing, red X?

little seacoast · « **Reply #23 on:** May 18, 2010, 04:00:42 PM »

VA Rifleman, If I may ask, where are you finding 2.175" shot? Almost perfect for my 2.25" bore. Thanks, LS
I too am trying to use what I have around, will have to look for some 2" stock that I'm willing to sacrifice for sabots, current ones are 1".

VA Rifleman · « **Reply #24 on:** May 18, 2010, 04:38:35 PM »

Quote from: little seacoast on May 18, 2010, 04:00:42 PM

VA Rifleman, If I may ask, where are you finding 2.175" shot? Almost perfect for my 2.25" bore. Thanks, LS
I too am trying to use what I have around, will have to look for some 2" stock that I'm willing to sacrifice for sabots, current ones are 1".

Hi little seacoast, Getting the shot from the gentleman that built my piece. Have 20 or so balls coming and the mold as well. Be willing to part with it if I could find something around 2.44"

VA Rifleman · « **Reply #25 on:** May 18, 2010, 04:41:02 PM »

Quote from: Double D on May 18, 2010, 03:22:55 PM

Here is a better angle angle on one of my sabots.

Using the sabot with the cast lead balls worked pretty good last at the Montana cannon shoot. I was able to knock down the metal cannon silhouettes quite regularly with them.

I'm not sure how the steel ball will work, they are lighter.

VA rifleman you say you can't see my pictures. What are you seeing, red X?

In the 1st post I see just a blank white box and in the last, just a white dot with no outline? Can see the other pics in this tread??

Double D · « **Reply #26 on:** May 18, 2010, 05:34:21 PM »

Right click on the boxes and see what it says. Anybody else having problems seeing my pictures.

GGaskill · « **Reply #27 on:** May 18, 2010, 06:06:58 PM »

Pix come through fine.

dan610324 · « **Reply #28 on:** May 18, 2010, 06:09:10 PM »

no problem at all

VA Rifleman · « **Reply #29 on:** May 20, 2010, 05:15:08 PM »

Double D. When right clicked, the show picture and all the link commands are grayed out. Problem is probably on this end as this network has filters on personal network storage though other pics come through. Don't waste any time mucking with this, Ill try on a different network.