Some frames from some movie clips

[John N]

The weekend weather for us poor folks in the Mid-Atlantic is a complete washout. Got to playing on my computer and found a free-ware video decompilier program that allows you to grab individual frames from movie clips. I've taken a few movie clips with my digital camera and I thought I'd share some frames from the movie clips with you.

Here's a half-scale coehorn firing a blank charge:



Launching a beer can.



A sleigh carriage mortar:



A swivel gun:



And finally a 1/5th scale 12 pounder:



I apologize for the size of this post . Cabin fever run amok I guess.

[das]

Your not the only one with the "Feaver" here !!!! The upper midwest has been a miserable place this winter also. But hey, great shots !!

[CAV Trooper]

SWEET!!!      :-D     :-D

[John N]

The rain has stopped and I should get a chance to fire my sleigh carriage beer can mortar from Canadian Cannon Company. It's a good strong piece but tends to flip over under recoil:



Lacking machining skills or tools (but immensely enjoying all the cannon building going on out there!), I added a metal plate to the base of the carriage which created a cavity. I filled the cavity with about 6 pounds of number 9 lead shot and sealed the top with another metal plate:






I hope this added weight will prevent flipping. If this doesn't work I'll have to add tie down rings to the carriage.

[Double D]

John that's scarey.

Can you tell from using the Movie freeze software where the can is when the flip starts?

Of course it flips over.  The bed is grossly undersized.  It's too short.  It needs to be longer and the  Trunnion needs to be centered or just slightly forward of the center line from front to back on the cheeks.  I also have some concern about the thickness of the cheeks.

Until you fix that bed, reduce your load until you don't get any flip.  Beside its just as much fun to watch them cans come down as it is to watch them go out of sight and never be seen again.

Guns mounted on a navel carriage had the same problem. They have a high center of gravity. That is one of the reasons they are were tied down with block and tackle.    My Boat howizter would flip when I shot slug from it.  That's when I started using the block and tackle to tie it down.  The Block and tackle also served as type of recoil mechanism and to drag it back to battery as well as aiming it.

I see you live in the PRM.  You will have to join us over at Ft. Shenandoah in May to watch the NSSA shoot.

[Will Bison]

Great photos!!!!

Ditto on the lousy weather. Same thing here in N. Nevada. More snow coming today.

[John N]

Double D:

Here's a picture of the flipping-over mortar showing the can in flight. It's the third frame after the charge went off (my camera's movie mode takes 15 frames per second).



I suspect mortars are like firearms with nearly all of the recoil happening after the projectile is out of the tube.

I just tried the mortar (in windy, drizzling weather) with a full charge of 1FG (the sub-chamber only accepts 250 grains). The added weight seems to have made a big difference. I still got a little rocking, but nothing even approaching a flip:



Here's the mortar at maximum recoil (3rd frame of action). The can is visible in this shot as a dark dot at the top of the frame.



Ft Shenandoah sounds interesting. My Mom lives in Grayling, Michigan and I plan to go up to Camp Grayling this year and check out the full scale shoots. I'll try to take some interesting pictures to share with the board.

[Double D]

That video compiler sure tells you a lot.  Not only can you analyze the recoil you can see the projectile go out of the gun.  In the one shot it couldn't be more than 8 to 10 feet out and tumbling.  I am going to start a new thread.

I strongly believe there is a viable market for someone to sell either a ball mould or other than lead ball projectiles in Beer can size.

I am having my Mortar bored out to  6 PDR just for this reason.  I can get  zinc 6 PDR balls and shoot them.

[GGaskill]

How much are you willing to pay for a zinc ball 2.6" in diameter?  It would weigh about 2.6 lbs and cost about $3.50 for the metal alone.  Labor, profit and shipping would probably double the cost.  It would probably make more sense to sell steel ball moulds.

[Double D]

George I am currently paying  $10 for a 6 PDr plus shipping.  $7 delivered is cheap.

[GGaskill]

Although I just bought some virgin zinc, don't hold me to that price figure.  I need to do a more detailed cost analysis before quoting a for real price.  Also, shipping cost per ball would depend on number of balls purchased.  The new $7.70 for up to 70 lbs USPS box would be economical if filled.  Probably would have to have a minimum order for shipping to be included.  

It looks like the larger box would contain 24 2.6" shot (32 cents each) and the smaller one would take 20 (38.5 cents each.)  That  leaves $3.12 or $3.18 for labor and profit.  With one mould, you might be able to make 20 per hour ($1 each at $20 per hour.)  That leaves about $2.15.  Then comes the issue of packing the box; even with an egg crate to hold the shot, loading and addressing a box is going to take at least 3 minutes ($1).  If it takes 6 minutes, there is no profit left.  Looks like $7 per ball is too cheap.  

So the question is, would there be a market for 2.6" zinc shot, two dozen (62.5 lbs) at a time for $192 ($8 each)?