Re: Loading Information- 3 inch Ordnance Rifle

[subdjoe]

On a different tack - has anyone here tried a patched round ball from a rifled gun?  I'm thinking that may be the way for me to go.  Full scale 3 Inch Ordnance rifle, land to land about 2.97, grove to grove about 3.09.  A 2.95 lead ball weighs just a touch over 5.5 pounds.  I don't have access to a lathe, buying projectiles is hideoulsy expensive, but if I can get a mold to cast a ball between 2.90 and 2.95 it just might work.  Comments?

[RocklockI]

personaly , no way . not . too much pressure /no windage , stuck ball going in ....

it dosnt sound like a good idea at all ......

[subdjoe]

personaly , no way . not . too much pressure /no windage , stuck ball going in ....

it dosnt sound like a good idea at all ......

Yeah, but I was hopeing.  I couldn't go much below a 2.90 either, I would need too thick a patch.  Ah, well.  It was a thought.

[Double D]

Any idea how you would drive a pacth ball down a bore that large and get it seated? Recall the amount of pressure is takes to get .59 call ball down a rifle barrel.  A 3 inch ball has a significantly larger surface area riding the bore, and even more friction that a .59 cal ball.

What did the original three inch projectiles look like?

[GGaskill]

You would probably be more successful trying to use saboted round balls.  But try to make the sabot remain attached to the shot.  Cut the sabot so the grain runs perpendicular to the bore axis instead of parallel.  Or make the sabot from a synthetic material such as UHMW plastic.

[subdjoe]

Any idea how you would drive a pacth ball down a bore that large and get it seated? Recall the amount of pressure is takes to get .59 call ball down a rifle barrel.  A 3 inch ball has a significantly larger surface area riding the bore, and even more friction that a .59 cal ball.

What did the original three inch projectiles look like?

First, thanks for breaking this out into a new thread. 

Seocnd, How? Brute force and determination. 

The originals were the Parrott, Hotchkiss, Schenkl, and the like.  A slightly sub-caliber conical projectile with something that would expand into the groves when the propellant charge went off.  Some were a cup of soft metal on the back, some a cup with an iron plug that would expand it.  The Hotchkiss and Schenkl were two parts with a lead or paper mache' belly band that the base of the shell would drive into and expand. See http://www.civilwarartillery.com/ under: field projectiles: rifled projectiles. 

Paulson makes them, but at $50 each, plus shipping, shooting gets very expesnive very quickly. 

[subdjoe]

You would probably be more successful trying to use saboted round balls.  But try to make the sabot remain attached to the shot.  Cut the sabot so the grain runs perpendicular to the bore axis instead of parallel.  Or make the sabot from a synthetic material such as UHMW plastic.

Hmmm....make a hollow based lead sabot.  That would expand into the rifling.  I know someone with a round ball mold that would make shot that would work, but I need to come up with something to engage the rifling.

I could get a mold made for the 'trash can' projectiles.  I looked into that and it was somewhat on the expensive side for us at the moment. 

That is my big frustration - lack of funds for getting things machined, and no access to a lathe. 

[dominick]

Subjoe,  Since you are willing to pour your own.   Wouldn't you be better off having a mold made where the projectile is skirted in the rear?  

[I see you got the idea already while I was typing]

A mold can be made from a piece of tubing split length wise, tacked together and bored,  It would need a split and domed plug welded in.  4" x 9/16" wall tubing has a 2.875" ID.  I'll send you a piece if you want to try to make a mold from it.

[subdjoe]

Thanks, Dominick.  I think I will take you up on that. I looked up Sched. 80 pipe and it has an ID of 2.90, so I was thinking of trying to find some of that.

I understand about needing a domed plug to form the cavity in the base, but what do you mean by "split and domed?"  I'm missing why it would need to be split. 

A few months back someone had posted drawings of a mold he had made for a hollow based projectile. I had printed it and took it to a machinist here and it would have been very expensive to have him make one (any one off piece will be expensive though). 

Joe


 

Subjoe,  Since you are willing to pour your own.   Wouldn't you be better off having a mold made where the projectile is skirted in the rear?  

[I see you got the idea already while I was typing]

A mold can be made from a piece of tubing split length wise, tacked together and bored,  It would need a split and domed plug welded in.  4" x 9/16" wall tubing has a 2.875" ID.  I'll send you a piece if you want to try to make a mold from it.

[Victor3]

 A guy on here recently posted a video of himself shooting what I remember to be a cannon he made from a 60mm(?) Japanese rifled Howitzer barrel. He was getting good results with a patched ball out of it.

 Maybe someone can find it. I remember the guy would say "send it" when he wanted his buddy to fire the gun in the video.

 I think a fairly light hollow-base lead slug should do the job for you...

[Double D]

For three inch you would be better of doing zinc and not lead.  A 3 inch lead round ball will weigh 5 to 5 5 1/2 pounds, conical even more. Zinc 3 1/4 lbs in a round ball, slightly more and closer to original in conical in weight.

Lead will run pressures up and will be require heavier loads to duplicate the original loads if you can.  The heavier loads will generate greater recoil and will be harder on your carriage.

Zinc is the better way to go in in these larger guns.


 

[Victor3]

 You're right DD. My mind is always thinking lead since I've got literally a TON of the stuff.

 Subdjoe would be better off with zinc, but a mould similar to the one I made above but for a shorter slug might cast some nice little "collar button" bullets from lead that would be lighter than a Parrott 3" solid iron shell (10 lbs).

 Also, aluminum moulds are cheaper to make than steel ones used for zinc...

[dan610324]

but it must be easier to find pieces of steel in the scrap yard to manufacture a mold from then to try to find aluminum pieces in that size
and probably cheaper also

anyone who knows the shrinking percent for zink when it solidify ??

how about this design ??
its somewhere in between a trash can and a minie style
would be easy to make such an mold

[subdjoe]

(scurrys around saving ideas)

Hey, this is great. Thank you all for contributing. 

I will likely go with lead because I have a (reasonably) local source for for lead at about the price for scrap zinc, which I would either have to pay freight on, or drive about 4 hours each way to pick up.   With gas at about three bucks a gallon, that really raises the landed cost. 

The designs that Dan and Victor suggest would give me projectiles in the 5 to 6 pound range, which is about what I'm looking for.   I don't want to go too light.  I have to believe that the designers knew what they were about when they came up with the size and weight projectiles they did. 

[RocklockI]

dan i'm not sure what the shrink rate is ? but i can tell you it aint much .

we had to tap ,,,, hit the mold in mont. those were some nicly cast zinc balls went they came out .

[dan610324]

I just know that bronze shrinks approximately 1,6% when it cool down

lets say that we would cast a solid bronze ball of 3" diameter (76,2 millimeter) the mold dimension
when its cold it would have an diameter of approximately 75 mm
so the shrinkage aint that small

you must absolutely calculate with the shrinking when you make the mold

but in this case you only have the thickness of the skirt to calculate from

another very important thing to think about is the alloy ,
if you use lead you should add between 4 and 6 % tin
that is to not get lead foulings in the bore
its neccessary as there aint any grease groves in the bullet

[Double D]

you might also check and see what others shoot in 3 inch Ordnance rifles...bet it ain't lead.

[Alangaq]

well... if cost is the main issue, and you got plenty of time, you could go get yourself a bucket of play sand, a sheet of blue board and carve your projectiles out of glued up blue board.  consistancy will be problomatic, but it will be inexpensive!  once you get a bunch of them carved up all you need to do is pack them into the sand, leave a sprue hole and dump in your blazing hot lead or zinc!  the foam goes away, and presto, you end up with a suitable projo!  they might be a bit wrinkley and they will have whatever texture the size sand you uses on them, but they will shoot...

google "lost foam casting" for way more info...

[Cat Whisperer]

A few years back I saw one of the bullets and the WINNING target from the latest N-SSA cannon competition, when I was in Petersburg, VA.

The bullet was about 3" in diameter and 3" long.  Square (flat) front, wall thickness about 1/4", hole in the back deep with flat bottom.  It cut clean round holes in the paper targets.  It was LEAD.

The tornado hit about 15 minutes later.  Fortunately we left just before.

[subdjoe]

well... if cost is the main issue, and you got plenty of time, you could go get yourself a bucket of play sand, a sheet of blue board and carve your projectiles out of glued up blue board. 
google "lost foam casting" for way more info...

I had considered doing a sand casting.  Find a wine bottle that has a deep punt and will also fit the bore (would likely be one of the half bottles), pound it into the sand to make the cavity, remove the bottle and pour.  Or use something like that to make plaster molds. 

Cost is a big factor, lack of access to tools is another.  I'm not an accomplished machinist, but I could turn my own projeciles if I had access. 

[dominick]

I understand about needing a domed plug to form the cavity in the base, but what do you mean by "split and domed?"  I'm missing why it would need to be split. 

I was thinking of the plug as part of the mold and not a seperate piece.  The separate one piece plug would work better.

[Double D]

(The designs that Dan and Victor suggest would give me projectiles in the 5 to 6 pound range, which is about what I'm looking for.   I don't want to go too light.  I have to believe that the designers knew what they were about when they came up with the size and weight projectiles they did. 

Slo that duplicates pretty close the original projectile weight? 

[subdjoe]

(The designs that Dan and Victor suggest would give me projectiles in the 5 to 6 pound range, which is about what I'm looking for.   I don't want to go too light.  I have to believe that the designers knew what they were about when they came up with the size and weight projectiles they did. 

Slo that duplicates pretty close the original projectile weight? 

A bolt for the 3 inch rifle weighed 9.2 pounds, and was about 9 or 10 inches OAL.  So, I'm going for a bit lighter and a bit shorter.  The service charge was on pound of powder.  I'm looking to use around 6 oz. of Fg (that is what we use for blanks at reenactments.  Cannon grade is a bit more expensive than Fg, so going with what we have).  The gun is from Steen, so the load is well under what the gun was designed for.  The bore was inspected with a scope a year ago and is as close to pristine as you can get. If we were to shoot competition we would work up projectiles and charges more carfully, but since we ar "plinking" we don't need that level of precison.

[Double D]

Just remember with Fg you get 40% more pressure for the same velocity as Cannon grade at $.50 a pound cheaper.