In the C17th Century there were three main ways for a soldier to carry his powder.
This seems to have been the most common way to carry powder in the early years of the century, but all the evidence suggests that it had fallen out of favour as a military solution among the footsoldiers at least. Those flasks carried by the common soldiers earlier in the period were normally made of wood, with iron re-enforcement and fittings, and were roughly triangular in shape. An alternative style was made of flattened horn, with the nozzle at the narrow end, and the other plugged with wood.
Although the regiment does allow the use of flasks for powder, they are not encouraged, for several reasons. Firstly, as above, they do not seem to have been normal equipment by the Civil War. Secondly, most flasks available commercially are not, in general, very historically accurate. Partly this is due to modern safety concerns, in that most accurate reproductions would not pass modern safety checks. Some good looking examples do exist, but are often not useable due to Sealed Knot rules.
This seems to have been the most common method for our period for musketeers. The bandoleer consisted of a leather strap hung over the right shoulder, from which was hung a variable number of capped wooden bottles, often 12, but sometimes 10, 8 or less. Each bottle was of a size to hold one charge of powder for the soldiers’ weapon. A leather bag hung from or built into the bandoleer would hold the corresponding bullets. Another bottle, sometimes somewhat larger, fitted with a spouted top, was used to contain the priming powder. Occasionally, especially earlier in the century, a miniature flask was used instead of a priming bottle. Sometimes there was also an attached oil bottle, for musket maintenance.
Although there are accounts of bandoleers being issued to dragoones, there are others which suggest that they were not really suitable for mounted use, as the motion of the horse caused cords to became tangled, the powder spilt due to tops coming off and so on. The use of bandoleers is acceptable in the regiment, but seek advice before purchasing, as some of the available ones are not historically accurate.
Various accounts make it clear that paper cartridges stored in a leather cartridge bag were used in the period. Among musketeers this may have been a stopgap solution, when adequate supplies of bandoleers were not available. The use of cartridges seems to have been more a matter of positive choice among mounted troops, and it seems that this method was used by at least some dragoones. Making up cartridges needs a bit more preparation, but can be a quick, reliable and flexible method of loading: indeed, it became the norm for all firearm users as time went on.
For Sealed Knot use, cartridges should be carried in a purpose made leather bag, which should be designed to protect from flash, sparks and rain, and of accurate style for the period. The empty paper cartridge is not to be used for wadding.