I just discovered a cheap but apparently accurate way to test lead hardness, curious is anyone has tried it.
In the vid, I am referring to the guy's use of lead sketching pencils of varying hardness. These can be purchased at any craft or stationary store for less than $10. Basically you pick up a set of sketching pencils and see if you can scratch the lead with them. Start wit a "6B" pencil, a soft one that matches up with pure lead. If you can't scratch the surface, move up to the next pencil on the hardness scale. When you can scratch the lead with the pencil, match it on the chart for corresponding hardness and you then apparently have a pretty good idea of the lead purity.
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SteveH
I did purchase the Staedtler pencil set and have been using this system for the past few years. Like the guy in the YouTube vid, I agree that this is an accurate and low budget way to measure lead hardness.
To verify the results, I tested metal from three sources: 1.) pure lead, hardball, and monotype purchased from RotoMetals, 2.) scrap lead scrounged from various sources, and 3.) an Ebay source claimed to be pure lead plus 1% tin to improve castability. The scrounged lead was taken to my local scrap metal dealer where the various batches were shot with an ex ray gun and exact percentages given like % lead, % antimony, % tin, etc. I have the exact same chart as the guy in the vid and in all cases, the pencil test proved to be spot on.
A few extra thoughts, however:
- You can buy cheaper brands of sketching pencils and save a couple bucks, but stick with the high quality Staedtlers.
- Rather than sharpen the lead to a point, you want to have a flat bottom. Take a sharp utility knife and remove about 3/16" of wood, leaving a stub of lead sticking out. Don't worry about breakage, as the lead is very strong. Get a piece of 400 grit Wet or Dry sand paper, and holding the pencil vertically, sand the end of the lead to a nice flat face with square edges. If you're concerned that the pencils may not last long, well, no more than I use mine, they're going to outlast my lifetime. Then, hold the pencil against the lead/alloy at about a 45 degree angle and push forward with just a little downward pressure. It's actually easier to do than it sounds, and just takes a little practice to get the hang of it. You're looking for the point at which the pencil either gouges the metal or rides across the top of it.
- One of the advantages to this system is that you can test any
size of metal, not just a bullet. You just need a small and relatively smooth spot on which to push your pencils.
- Recently on this forum in other threads, mention has been made about how even small increases in hardness can affect accuracy, point of impact, and loading difficulty with muzzleloading bullets. Using the pencil test, I unfortunately was not able to tell a difference between certified pure lead and the lead-plus-1%-tin (with small amounts of other non-pure lead mixed in) that I had been using for casting my bullets. The softest lead pencil leaves a similar gouge mark in both metals. I have no idea if genuine hardness testing tools can detect such small variances. At my last casting session, I switched over to pure lead, but I'm still in the testing phase to see if it affects my loading/shooting.
In summary, I heartily endorse the pencil testing systsem.