Jack, I've been using a standard RCBS Uniflow powder measure for some time to measure out black powder. These have a plastic hopper. I did some detailed testing on the shock and static-electric. sensitivity of black powder some time ago and I firmly believe the warnings on black powder are over stated. See further comments one the subject below. But if you are concerned, one can't be too safe when handling powder, you can static-proofed any measure by simply lining the plastic hopper with a sheet of very thin brass, the stuff you can buy at hobby shops or is also known as shim stock to mechanics and machinist. An even simpler method is to line the hopper with aluminum foil.
============
I'm not trying to get into a major discussion on BP safety but following is some additional comments on the subject, and is the basis for my opinion.
A fella by the name of Barry Bush published two excellent and lengthy articles on black powder safety in the 1999 spring and summer editions of The Black Powder Cartridge News. Mr. Bush is obviously a very knowledgeable guy and did a good amount of experimenting to determine the sensitivity of black powder to heat, pressure and static elect. ignition.
To summarize, he found BP much more sensitive to heat than smokeless. He also found that BP is not very sensitive to shock, and is much less sensitive to high voltage sparks. He passed sparks of up to 20,000 volts directly through powder with absolutely no ignition. Goex Fg, 2Fg, and 4FA (unglazed powder) was used. The 4FA powder was used to see if the lack of graphite would allow the powder to ignite. A sample of Red Dot ignited and burned easily and every time. He said that it is conceivable that a 100,000-volt spark from a fingertip could ignite BP, but the chances are very remote. He further stated that smokeless has been known to spontaneously combust in very large quantities due to heat created in the decomposition process. He explains why BP will never spontaneously combust.
In summary he said, "Many common perception of black powder come from those who lack practical experience, and they often reflect confusion with other explosive materials." He further stated "Modern smokeless powder has an excellent safety record, but in some respects smokeless can be more dangerous than black: it is more likely to give extreme pressures from an overload, more susceptible to decomposition, and under some conditions, more sensitive to electrical discharges. In closing he said: "Black powder has managed to outlive most of its detractors, and hopefully will continue to do so. Meanwhile, shooters can ill afford to repeat folklore, speculation and hearsay which may come back to haunt them."
The last sentence refers to past and possible additional government regulation on BP due to incorrect and misleading information. I'm certainly not posting this to imply one can be careless when using BP, but these articles are definitely worth reading. Just may make you rethink the warnings we in the shooting community have been passing around about BP.
---------------------
I ran my own similar experiments with BP (Goex 2Fg and 3Fg) a few years ago, with similar results. I pounded it to dust with a hammer with no reaction. I subjected it to high voltage discharge (to over 100K volts) with a hand tester used to test static discharge damage thresholds in integrated circuits. None of the samples ignited.