Author Topic: How to attach sabot? (Read 2451 times)

Evil Dog · « **on:** December 23, 2008, 03:22:05 PM »

With any luck I am within a couple weeks of making smoke and fire again. My half scale Napoleon has been sleeved down to a golfball bore... now it is time to make up a few solid shot rounds for it. Cutting suitable plugs from a good grade of plywood is no problem at all, a 1 7/8" hole saw yields a "wheel" within about 1/8" of the size I need. Glue 2 of them together and lathe them down to the proper size. Then use a 1 1/8" spade bit to create a cavity for the ball to set in.

Now comes the question... how to attach the sabot to the ball. Do I want it to remain attached to the ball until impact or do I want it to be discarded after leaving the muzzle? Permanent attachment would be no problem, just run a sheet metal screw up through the sabot into the ball. For a discarding sabot though I am thinking either a couple pieces of masking tape holding it all together or perhaps a bead of silicone sealer between the sabot and the ball.

Any suggestions?

Double D · « **Reply #1 on:** December 23, 2008, 03:38:28 PM »

Try both, and report back.

thelionspaw · « **Reply #2 on:** December 23, 2008, 03:45:40 PM »

Originals were launched with tin straps attached. You might try cutting the sabot out of a pine board with a hole saw and then spade bit it as I do.

RocklockI · « **Reply #3 on:** December 23, 2008, 04:19:06 PM »

Very interesting . I'm wondering the same thing with my golf ball cannon .

Are those balls lead ?

rocklock

Evil Dog · « **Reply #4 on:** December 23, 2008, 04:25:41 PM »

Yes, the balls were cast from scrap wheelweight. Look around for a mold to cast a 1 pound "cannon ball" fishing weight. It will work quite well instead of using golfballs. Expect a bit more recoil though.

seacoastartillery · « **Reply #5 on:** December 23, 2008, 04:28:03 PM »

Could someone explain why these sabots are necessary at all, especially in this size? If you are concerned about your ball simply rolling down the tube before you can fire the piece, why not keep it simple and put a dab of white glue on the top of your foil powder charge and a couple drops on the ball then wait twenty minutes, then reactivate the glue with one drop of fresh glue and push the ball into the foil charge end firmly. You can do 50 in twenty minutes no problem. In three hours they are ready for use. Glued THIS WAY they WILL NOT separate until this simpler form of "Fixed Ammunition" is fired. Same effect, but much less work. Merely a suggestion.

Regards,

Mike and Tracy

Evil Dog · « **Reply #6 on:** December 23, 2008, 04:32:46 PM »

When my half scale Napoleon was a 2 1/4" bore I had trouble hitting a 4'x4' piece of cardboard at 75 yards... there just didn't seem to be anything resembling a group. When I started adding sabots I was able to place every round in that same target at the same range. I am presuming that I will experience more or less the same with the bore now being sleeved down to golfball size. Will also try a few naked balls just to see how it compares.

Artilleryman · « **Reply #7 on:** December 23, 2008, 04:49:38 PM »

I think you have answered your own question. Let us know how it works.

thelionspaw · « **Reply #8 on:** December 23, 2008, 04:56:16 PM »

M&T: I made mine for the historicity as you can see. It's all part of the educational process and the, "Oh wow!" factor when kids handle the static display as shown.

rc

Double D · « **Reply #9 on:** December 23, 2008, 05:52:33 PM »

I also believe the purpose of the sabot was to act as well a sabot and center the ball as it went down the bore as it was fired.

I can only wonder if when the fired if the original's separated. Where they designed to shatter and break up when exiting the muzzle to be blown apart by the muzzle blast as the ball left the bore. The construction would be critical if you wanted the sabot to disintegrate. The ball would have to sit on the end grain.

ED what happened to the sabot you fired before? Did they break up or stay hole?

Evil Dog · « **Reply #10 on:** December 23, 2008, 06:23:41 PM »

The sabots always stayed pretty well intact as they were made from plywood. Some of the ones I'd found down range actually looked as they could be used again. Of the 3 in this picture, 2 of them have been fired and recovered downrange. These were affixed to the ball by 2 crossing pieces of masking tape.

I would wonder about the masking tape releasing though. Should it all release at the same time the ball should continue on a straight flight. If it only partially released though then could the dragging of the sabot until the rest of the tape released cause the ball to go off in someother direction? That was my thought when I tried the permanently affixed sabot.... if it doesn't detach then all of the rounds should be pretty much the same by not having the variable release of a sabot. Made sense to me at the time.... sorta still does.

cannonmn · « **Reply #11 on:** December 23, 2008, 07:33:51 PM »

One of the accuracy contributions of the sabot is to keep the spherical projectile from taking a random spin as it goes down the bore. The great pressure with which the sabot is pressed onto the ball will prevent the ball from rotating as long as the sabot is pressed onto itk, perhaps even in flight if the sabot doesn't break up. The way I understand it, the random rotation of the ball in flight, in pre-sabot days, was one reason why smoothbores were so inaccurate. If someone already mentioned that, great, often I don't read too carefully.

Victor3 · « **Reply #12 on:** December 23, 2008, 09:15:46 PM »

Some random thoughts...

I think if I were to use that type of sabot, I'd glue a 1/4" dia pin (a wood dowel might work OK too) through the center with about 1" sticking up past the bottom of your spade-drilled pocket. Then drill a hole in the ball that the pin would slip-fit into.

You could even drill clear through the ball in order to keep the weight balanced. This should also help the sabot separate more uniformly on all shots since air would be forced into the hole after pressure drops off from the charge after it leaves the bore.

To make things simple, you could just press/glue a bolt of correct length through the back of the sabot with the threaded end sticking out the front.

Also, I'd be sure that the ball is resting on the bottom of the pocket and not only the outer edge at the inside diameter of it. If it's contacting only on the edge, it's more likely to break during firing as the ones you show appear to have done. If you wanted to get fancy, you could fill the pocket with plaster of paris and 'cast' the ball onto the end of the sabot for a perfect fit.

My thinking here is that the pin will hold the ball centered on the sabot as you load and fire, yet let it come apart easily after the round exits the bore.

As a side benefit, you might get a cool whistling sound out of the ball

GGaskill · « **Reply #13 on:** December 23, 2008, 09:46:14 PM »

I think, like cannonmn, that it is desirable to keep the sabot attached since it will act like a tail, providing drag that keeps the shot facing forward. Same idea as a conventional Forster hollow base shotgun slug. I would screw them on.

Artilleryman · « **Reply #14 on:** December 24, 2008, 04:15:38 AM »

One reason for the sabot was to make it easier to attach the powder bag to the projectile. They did come off and could cause injuries to your own troops if you were firing over their heads.

KABAR2 · « **Reply #15 on:** December 24, 2008, 04:24:25 AM »

Cannonmn is on the right track, the ball not being actual bore size can develop a little bit of "bounce" as it goes down a smooth bore wheather
it's a cannon or a musket, when it leaves the bore gas can escape along one side of the ball throwing it off slightly this yaw is why some find they can't hit a piece of cardboard with a ball, the Sabot stops the "bounce" and allows it to exit the bore more "centered" so gas escapes
evenly, I have fired more smooth bore musket rounds than cannon, and the aluminum foil I used for the cartridge acts as a sort of sabot these balls are more accurate than a naked ball from the same musket. you would get the same result "patching" a ball in a musket
as it stops bounce. hope this makes sense.

Allen <><

dan610324 · « **Reply #16 on:** December 24, 2008, 07:52:20 AM »

Ive seen shotgun slugs that bee "rifled" at the outside ,
dont know if its just cosmetic or if it actually helps to spin the slug .

but it could be interesting to test with an permanently attached sabot .
rifle the outside in an 15 degree angle to see if it maybe will help spinning the ball to get tighter groups

ratpatrol · « **Reply #17 on:** December 24, 2008, 09:42:38 AM »

You guy's are onto the right track for shooting round ball accurately. I have over 15 first and second place wins using a sabot attached to the ball. My thoughts are that a ball in a barrel has a very small sealing area, gasses will leak at the loosess place cousing it to spin- not on its axes like a rifled bullet- this couses hooks and slices, have you played golf or bowled and watched the ball take off .
This is what I do. My barrel bore is 1.700 I use a hole saw minus the 1/4 bit but use a pointed rod to mark center and cut out a plug, I clean up the edges on a sander, there are two ways to from here, one is too screw a 1 inch dry wall screw throu the plug ,3/4 plywood,has to be a tight fit in bore, grease the plugs OD , use a ramrod that will not hit the 1/4 end of screw sticking out and load cannon,seat the sabot, load the ball and hit it into the screw, that will stick into ball and stop any un wounted spin whin fired. The other way is to make a jig that is bore size of cannon and ball and lag scew sabot to ball, the sabot stays on the ball and it hits straight on, The other thing to make a sabot out of is high densety poly erathane, white plastic cutting board materal, has tobe a least a 1/2 inch thick to seal

dynomike · « **Reply #18 on:** December 27, 2008, 09:07:23 AM »

I guess i am missing it. How much clearence does the sabot have in the bore if any and how thick is the sabot 1.5"?

ratpatrol · « **Reply #19 on:** December 27, 2008, 08:38:51 PM »

A good snug fit is ideal. Thickness is up to you and how to make them, I use a 1-7/8 hole saw and a good grade of 3/4 " plywood.I have not tried turning a rod and cutting plugs I think end grain would split out ,If you have a wood lathe try a good hard wood and see.
I got a good 1lb fish weight mold, balls are 1.625 to small for my 1.700 bore cannon so I made tooling to swedge up to bore size, this maybe hard to explain, I had a 4in piece of 4 in round , I bored it to bore size, made a plug about 1 1/2 and turned a 1 half ball radius in one end also a slip fit to the 4in round, also a short rod , slip fit and a shoulder to stop whine it hits top of die . How it works is I drop a ball in half round plug and put outer die over ball ,install shoulder plug and hit with a large hammer until It fits die bore, The flat end of ball I install a sabot and screw or nail on while in it's in the die, grease it up and shoot, They fly straight.

Cat Whisperer · « **Reply #20 on:** December 28, 2008, 02:16:58 AM »

With a swaging die you are also ensuring uniformity of size and shape - which is good when fitting it to the bore.

dynomike · « **Reply #21 on:** December 28, 2008, 06:26:13 AM »

Correct me if i am wrong. My bore is 2 3/8"or 2.35 which a 2 1/4" ball should work but my mold advertised as 2 1/4" turned out to be 2 1/8" so i need to cut a 2 3/8"x 3/4 or 1.5" sabot from plywood then maybe sand it down to fit fairly tight. Will this work? I have been kinda leery because the ball cannot fit tight in a smooth bore. I am not in to busting barrels yet.

Cat Whisperer · « **Reply #22 on:** December 28, 2008, 07:02:23 AM »

"tight" is a relative term; greatly affected by how smooth and uniform the bore is.

What is the nature of the inside of your cannon? Is it rough cast? Has it been bored? Has it been reamed? Has it been honed?

You need to ensure a smooth sliding fit.

Clearance, windage, allows for some variation in sizes.

With smoother finishes and uniformity of size one can reduce to SOME extent the amount of windage.

The cost of reducing widage is higher pressure as less is blowing by.

GGaskill · « **Reply #23 on:** December 28, 2008, 07:57:33 AM »

I have been kinda leery because the ball cannot fit tight in a smooth bore. I am not in to busting barrels yet.

If you are concerned about bursting your barrel, then don't use as much powder. No point in putting it in just so it can leak past the shot. Remember, windage was to allow muzzle loading past the accumulated fouling from previous shots; pressure reduction was an inevitable result of the imperfect fit. Once they went to rifled guns, the sealing that resulted from the various methods of engaging the rifling prevented the blowby.

dynomike · « **Reply #24 on:** December 28, 2008, 08:21:39 AM »

I think i am compertable with it now i guess due to the ball size 1.5" would be better than 3/4". I have honed my barrel that is why i came up with 2.35 instead of 2.25 maybe. I bought the barrel used as far as i know i think all it has had is blanks shot through it except that pool ball i shot in it.I guess im getting ahead of my self i still have to make my trounion plates but right now i have nothing else to do.

Evil Dog · « **Reply #25 on:** December 28, 2008, 11:28:02 AM »

Been doing a bit more thinking (I know, that can be dangerous) concerning a discarding sabot or one that is permanently affixed. In my past experience, accuracy (such as it may be) is obtained by making everything as consistent as possible. Since my half-scale Napoleon is a smoothbore I would expect it to behave like the rifled bore guns.... don't dream of hitting paper plates at 250 yards. Staying inside of a 3' circle at 250 yards would be nice though. I'm not going to start weighing each and every ball either... I'm in this for fun, not big buck prizes. That being said, the easiest variable to eliminate would be the sabot release... run a sheet metal screw through the sabot into the ball and it should stay attached until impact. The other possibility would be to run a piece of 1/4" dowel through the sabot with it inserting maybe a half inch or so into the ball. A 9/32" hole in the ball should allow the sabot to discard pretty quickly. Either way it will have to drop easily through my 6" long bore gauge.

I've almost got my half-scale ready to go again... amazing what a little bit of paint and a whole lot of time will do. Hopefully I will be able to take it to the range the first weekend of the new year. My local range is limited to 100 yards but that should be far enough to try attached vs discarding sabots

Come the 5th of Jan I will be an officially retired fixed income senior citizen so will have more time to experiment.

Double D · « **Reply #26 on:** December 28, 2008, 11:43:11 AM »

Quote from: Evil Dog on December 28, 2008, 11:28:02 AM

Come the 5th of Jan I will be an officially retired fixed income senior citizen so will have more time to experiment.

That's what you think!

ratpatrol · « **Reply #27 on:** December 28, 2008, 03:43:28 PM »

Evil Dog welcome to the RETARDED group. It won't be long till you will find that "How did I work and still had time to play" The best part is getting paid for playing.

The bad part is Your body has gone sour.

Dynomike---2 3/8 is 2.375 Honing a 2.250 bore out ,.100 is a lot of honing. My I advise getting a dial caliper. If your ball is that loose in the bore sabots would help, thickness I think should be close to bore size, and cupped to center ball. Yes thing could wedge if sabot is to thin and ball to small.
This may not be the thread spot , If you have excess to a mill and a rotary table I can tell you how to make or redo a round ball mold.

dynomike · « **Reply #28 on:** December 29, 2008, 12:41:44 PM »

The bore is 2.354 i did'nt measure it till after i honed it. I bought it as 2.250. I dont know maybe the sleeve had the 39/40 rule for 2.250. I wished i could hone my mold out but i dont know of anyone that has those tools that i could use, but i will check.

dan610324 · « **Reply #29 on:** December 29, 2008, 03:54:47 PM »

ratpatrol

please open an new post in the subject how to build your own ball mold
I suppose many here would like to know