I have owned one since about 1985. It became a necessity when cutting up a 5 ft diameter oak. Worked like a charm and I still have all of my fingers.
They can be made in many sizes depending on the job at hand. Mine is 13" long x 2 1/2" diameter with a 1" hole bored in 6" deep. Fully charged it holds 1/3 lb of powder for the big stuff. For small logs....say 3 - 4 ft diameter I cut them in 12 feet sections and split the log the full length.
For best results, Place the wedge over a split in the end of the log. If the split is running a couple of different directions place the wedge at the point where they meet.
Before placing powder in the wedge, I drive it into the log 1/4" or so. The wedge is then loaded with powder and placed back into the log with the touch hole facing up and a log is rolled against the back end. An 8" long cannon fuse is inserted so that it is hanging down, below the touch hole. No chance of the powder per igniting that way.
Once the fuse is lit, walk, don't run, at least 50 feet away and stand behind a tree if one is available.
Sometimes, I end up with 3 to 4 12 ft long log sections if the grain / cracks are running right.
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