become "sticky" and wants to bridge in my RCBS Grand. I bought some powdered graphite to maybe recoat the shot with and make it slick again. Has anyone ever done that before?

Yup but I used the motor mica from ballistic products.the white stuff .mb

It doesn't take much... less than half a thimble full in a case polisher.

I tried the graphite some years back, it was a mess. I found the best way was to graphite it and mix it about 1/3 old shot with 2/3 new shot.

I can do that. How much graphite did you use. I only have vibratory brass polishers and not a rotary one which would be needed to do this. I thought about taking a dry 2 liter soda bottle and mixing it all in that by rolling it a bit?

Soda bottle should work fine, just don’t had too much graphite. We frequently did this with reclaimed shot.

Put about 5 pounds of the oxidized shot in you vibrator with several ~3/8" steel hex nuts. Vibrate for a few minutes, then use a shop vac to remove the dust. Add a pinch of graphite and vibrate a couple minutes. Mix 50/50 with shiny shot. Is lead dust bad for you? Yes, use one of your covid masks and then throw away.

I had an old vib feeder bowl that I used and I most likely used too much graphite

Since the mid '80s I've made over 7 tons of my own shot. I've tumbled all of it, 12-15# at a time in my Thumler's Tumbler with just enough powdered graphite that a small flat screwdriver can pick up and added to each load. The shot comes out very smooth and shiny, and will easily meter in all loads down to .410.

How long did you run it in your tumbler?

2 hours

I never really timed it when I was doing it, I would put it in and go do something else. When it looked about right, I was done. I would guess that buffybr is about right.

Well I tumbled all of my oxidized shot with a bit of graphite powder. A little goes a long ways for sure. It did not come out shiny but it is jet black and pretty slick. I bought a tub of graphite on amazon and I now have enough for 3 lifetimes.

I think I went to Walmart and got a tube back in the automotive section that you use in car door locks, that was way more than I needed as well.