Author Topic: New guy saying Hi ! .... and a question too.... (Read 747 times)

Soot Sucker · « **on:** August 26, 2004, 03:09:33 PM »

Hello from a newbie mortar guy. I have a few muzzleloading rifles and a colt 1851 navy pistol.

I purchased (last month) a golf ball sized (bore) mortar. The mortar is Machined from solid steel (what grade, I know not) it weighs 20 lbs, is aprox 8" long and 4 1/2" wide at its muzzle. It has a powder chamber.

My question is what grade of powder should I use 1FG FFG? and at what charge... I want to start out low and slowly go up... but where to start?

I have been reading alot about safty and precautions but am not getting alot of info regarding actual charge amount/weight.

Respectfully to all....

Double D · « **Reply #1 on:** August 26, 2004, 03:25:36 PM »

You need a copy of THE MORE COMPLETE CANNONEER compiled Agreeably to the Regulations of the War Department as published in "Artillery Drill" by George Patten, 1861 and Containing Other Observations on Antique Cannon By M.C. Switlik with selected excerpts from other artillery manuals there is a chart in the book that gives loads.

Mortar charges are determined by the size of the powder chamber. A golf ball mortar shouild have a chamber large enough to use 1FG no finer. Your powder charge will be determined by the diameter of your powder chamber. Tell me the diameter and I will look it up for you.

Soot Sucker · « **Reply #2 on:** August 30, 2004, 08:41:29 AM »

Thanks Double D

Sorry it took me awhile to figure out the best way to measure the powder chamber. The best measurement I get is 3/4" x 3/4"

Thanks!,
Soot

Double D · « **Reply #3 on:** August 30, 2004, 09:13:15 AM »

Maximum load is 75 grains by weight of of FG.

I'd start with 65 grs and work up.

Soot Sucker · « **Reply #4 on:** August 30, 2004, 12:25:23 PM »

Thanks Double D for the quick response.

If using 75 grs at a 60 degree angle how far would you estimate the golf ball will go? if you know.....thanks

Soot

Cat Whisperer · « **Reply #5 on:** August 30, 2004, 12:46:01 PM »

Quote from: Soot Sucker

The mortar is Machined from solid steel (what grade, I know not) it weighs 20 lbs, is aprox 8" long and 4 1/2" wide at its muzzle. It has a powder chamber....

Steel is going to be tougher that cast iron (cast being generally more brittle). It sounds overbuilt - that's good. DD gave you a SAFE charge from standard calculations. You'll find that mortars have less length to burn powder therefore usually use a faster powder. Shooting golf balls is much less strain on the tube than shooting cast what-ever material - as they're very light.

In my hand-held golf ball caliber 'hand gonne' I use 2 cases (45acp) full of FFFg. That's not much. That will put one or two golf balls (it's 2 calibers long) out there between one and two hundered yards. Longer barrels will get much more range. Looser bores (mine's tight) will get less range. More powder - more smoke, not necessarily more range or velocity. It seems like your tube is a bit longer - you'll easily be able to get some LOOONG range.

Soot Sucker · « **Reply #6 on:** August 30, 2004, 06:38:20 PM »

Thanks Cat Whisperer for your input.

I was hoping that I could use a faster powder such as FFG or FFFG because I called 3 local gunshops and nobody carries FG. Also this is good news as I already have 9 lbs of FFFG left over from when I used to reload blackpowder cartridges.

A few more questions please...
1) is it ok if the powder does not fill the powder chamber (air space)? or should I make a "quasi" powder bag (aluminum foil)?
2) if not, can I pour the powder directly into the chamber? should I use a long funnel?

Thanks to you both for your help... it is much appreciated.

Respectfully,
Soot Sucker
(Dave)

Cat Whisperer · « **Reply #7 on:** August 31, 2004, 12:43:19 AM »

FFFg burns much faster, hence higher pressure. So start with small loads and build up. With golf balls it will soon be apparent that you can only see them if you're directly behind the piece because of velocity. Then you won't be able to see them at all, unless the sun is right behind you.

A little extra air in the chamber is no big deal.

Aluminum foil packets are good, but not necessary. Sparks are bad and cleanliness and time between rounds assist in their prevention.

On one of my mortars (16-20-24oz soda pop bottle caliber) I use a 1/2" pvc pipe 24" long and a funnel to put the powder into the chamber.

Note however, you should spike the vent and swab the chamber and bore between every shot. I have SEEN glowing embers of fuse fragments IN THE POWDER CHAMBER (could have been in the fuse vent) some TWO minutes after firing!

That also implies measuring the powder into a separate container and capping the 1 lb can and putting the 1 lb can well back from the firing position.

Rigid safety procedures are good, even if they only save your life/eyesight once in every 1000 rounds.

Double D · « **Reply #8 on:** August 31, 2004, 03:06:56 AM »

As long as you have windage in your projectile you don't need to orry about the air space.

As to range with the load, you will just have to try it and find out. Just remember you aren't trying to put the ball in orbit and half the fun of shooting the mortar is watching the ball fly through the air.

As CW says the FFFG is more energetic, that will increase velocity and increase pressure. neither things need in in a mortar Get as course a grain powder as you can find.