If by Jacobean you mean the period from James I ( 1603) to the Glorious Revolution of 1688, starting out for foot soldiers there would be matchlock arquebuses and muskets. Pistols would be wheelocks ( often seen in the hands of cavalry) and there were both matchlock and wheelock hunting rifles, shotguns. Around the time of the 30 Years War, plug bayonets would be invented, and bayonets would gradually eliminate the need for pikemen. At about the same time workable flintlock guns appeared in France- these would pretty quickly displace wheelock weapons, but low-cost matchlock muskets would persist into the Glorious Revolution. Also, perhaps because armies wore less and less armor, the heavy arquebus became the lighter musket ( though both terms were old, and for some time both names continued to be used)) , which did not require the support of the forquine, a stick with a fork in the top to support the muzzle of the gun.

These were all muzzle-loading weapons. Breech-loading small arms existed, but were quite few- they were very expensive because of the great amount of hand-fitting required to get a workable seal around the breech. Bandoliers of small wooden bottles, each containing a ball and powder charge, would be somewhat common until the 30 Years War, after which soldiers generally had a large pouch on their belt that held individually-wrapped paper cartridges. That cartridge box with paper cartridges would become pretty standard equipment until the advent of breech-loading guns with metallic cartridges in the mid 19th c. Soldiers using matchlocks would also have a powder flask for priming the pan, and hanging from their belts a sheet-metal tube that held the coiled slow-burning match cord. When assembled into lines before a battle, they would pull the match out of the tube and clamp it in the cock. As you can imagine, it was safer to keep the lit match away from the bandoliers until it was needed: if one of those small bottles blew up, it could set off the rest.