Some useful values:
1 grain = 0.037 dram
1 pound = 7000 grains
1 pound = 16 ounces
1 ounce = 437.5 grains
1 ounce = 16 drams
1 dram = 27.344 grains
Density of lead is 11.34 gram/cc
1 gram =15.4324 grains
1 inch = 2.54 centimeters
1 meter = 39.37 inches, 3.28 feet and 1.09 yards
pi = 3.14159
Volume of a sphere = 4/3pi R3 (4/3 x pi x radius of sphere cubed)
Radius of a sphere = cube root of (3Volume/4 pi)
Volume x density = weight


Are you sure what it says on the barrel. According to the values I found 1 dram = 27.344 grains. Hence 3.4 drams would equal 92.96 grains which would be about right. 34 drams by the same standards would equal 929.696 grains which would mean a blown up rifle and a dead or injured shooter....

Your rifle I am sure would safe with 100 grains of powder and probably more. I would suggest finding the company on line and seeking more load information from them. Until then, for your own safety, keep your charges 100 grains or less by volume and you should be fine.

Sometimes the charts I find on other sites seems a little more then I would have guessed. My .58 caliber rifle for example has a max charge of 120 grains of FFg powder....

Hope this helps...