powder load question

[TNmike]

how much powder should I use in a cannon with a 3.75" bore and a 6ft barrel?  Also what weight projo should I use?

[Double D]

Go up to our sticky note at the top of this forum and look at the safety procedures. In there you will find the criteria for determining loads.  It's part of the ten basic safety regualtions, Number one.

Powder charges should not exceed 2 oz. of Fg or 3 oz. FFA or Cannon Grade Goex powder per inch of bore diameter. No excessive charges. Use black powder only.

 Based on the rule your maximun charge would be 7.5 oz. of FG or  11.25 oz. of FFA or Cannon grade.

[Cat Whisperer]

TNmike -
  Sounds like a LONG range shootin' iron!  ASSUMING that it's built correctly you could calculate the weight of a 3.75" sphere of iron.  You'll find that iron and zinc weigh about the same (and zinc is much easier to cast).  At 3.75 you could even cast from lead, with a reduced charge to accomodate the increased mass.

  I've found that one needs a heavy bullet to get the powder to burn well.  But having seen (up close and personal) one cannon explode, I'd start with a reduced load and work up.

  I agree with DD - slow powder for the long barrel.  With my mortars I use much faster stuff because the barrels are VERY short - makes them easier to carry around and more muzzle blast is good for getting folks attention.

  Good luck, be safe and send pictures!