Re: Rainbow Tungsten Beads...?
I didn't make it clear in my previous post. I use tungsten beads for tying almost exclusively. I have some brass that I use for either double beads, or singles if I am not looking for the depth the tungsten provides. Sometimes I use a few wraps of tin wire, or lead tape to the shank. Sometimes, I double up on tungsten beads for certain patterns. I find the extra bit of cost worth it because it makes for a better fly IMHO. More weight on the fly, less shot, if any, needed on my line.
What I question about rainbow or color of bead for that matter is the color itself. Does it really make a difference to the fish? This is the piece that I think MIGHT be more appealing to the buyer or tier than the fish. Though a spin fisherman might suggest "sunny silver, cloudy copper (or gold). Black is one of those colors that seems to work regardless of conditions.
I think it always comes down to this: Size, Shape, Color. If you get at least 2 of those three with a fly you're likely going to get into fish. Add to that depth, you've got to get it down when nymphing especially. I agree with your notion on tungsten dillon. Interesting story with the sourcing and background of the beads.
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