New York Times, August 5, 1878. Yes: cartridge placement would be key here. Standard operating procedure among ghouls was not to expose the whole coffin, just the top half. Then the lid would be prized up with a bar and/or hooks. The soil pressure on the lower part of the coffin helped lever the lid upward. Then the smallest dude in the crew would get down in the hole and run a rope under the armpits of the deceased, who could then be extracted with a quick heave-ho. The best of the trade took pains to restore the grave to an ostensibly undisturbed condition–leaving a mess was bad for repeat bidnis, see? Sometimes mourners would leave small tokens on the grave–a stick or a stone–as a quick way of determining if the site had been disturbed, but the ghouls knew about this trick too and did their best to anticipate it. Anyway, this torpedo gizmo apparently found a market and sometimes worked, judging from this prior post.
P.S. To those who like this sort of thing, may I recommend this excellent book.
Georgia Weekly Telegraph, April 16, 1880. The level of detail here proposes sort of a PSA agenda: Robbing graves isn’t cool, kids, plus it can liquefy your eyes. This item would make for a swell high school instructional film, or an equally fine E.C. horror comic. 
Kansas City Evening Star, January 18, 1881. I suppose an unexploded bomb in every grave would have slowed down the trade in stiffs for a while, but there’d have been public safety issues, and eventually medical schools would have started offering bomb-disposal courses and we’d have been back to business as usual. Life is an arms race. 
Various newspapers, 1870-1909. Like so many other once-great American institutions, the trunk mystery has gone where the woodbine twineth. 
Chicago Tribune, June 23, 1878. Could be this interview is vaguely on the level, could be it’s a total put-on. It’s worth noting that “cunny” was then a well-known term for ye nether lady-parts of the fairer sex at a time when the general vocabulary lacked polite equivalents. It’s a noun now generally forgotten except by attentive followers of HBO’s Deadwood. Anyway, the ensuing description of the mechanics of body-snatching has an impressive verisimilitude. 
Chicago Tribune, July 19, 1860. Chicago is currently weathering a really revolting 
Chicago Tribune, March 20, 1921. I think we all instinctively feel the same way about “brown spirit rays,” whatever their source. Then again, if Egyptian mummies turn out to be the primary or sole source of these brown emanations, then charges of Orientalism are sure to follow. In that case, our very favorite color of spiritual radiation is brown–we don’t want any trouble from the late Edward Said’s ronin bodyguards. 
Detroit News, May 5, 1931. Pardon the fuzzy reproductions, but allow me to transcribe: 