From PyroGuideEditAluminum ramsA rammer is a tool made of a non-sparking material such as aluminum, nylon or wood. It is used to compress pyrotechnic compositions, often in conjunction with a wooden or rubber hammer, or a type of pressing device (hydraulic press). Typically compositions that are not sensitive to shock or friction (e.g. black powder) can be safely rammed. Compositions that are sensitive to friction or shock (e.g. a composition containing sulphur and a chlorate) should not be subjected to the forces of ramming, as it could cause ignition.
Plastics such as nylon can generate static sparks if the rod is pulled in or out too quickly, therefore metals like aluminum, brass or copper are best suited for use as a rammer, because any electric charge they pickup will quickly dissipate through the loader's grounded hand.
These aluminum ramers can be bought at http://www.pyrodirect.com/ccp0-catshow/alumrod.html