Sunday, October 4, 2015

Shake and Bake powder coated bullets

In order to save money on components for handloading ammo, many folks cast their own bullets. The problem with cast bullets especially once you start pushing them beyond 2000 feet per second is that you get leading in the barrel. The .223 caliber is going near 3000 fps out of a modern semi auto carbine so up to now the word has been no-go on cast bullets for them. So you are limited to buying jacketed or plated bullets which cost about 20 cents with every trigger squeeze. Add to that powder and primer (not counting case cost) and you are pushing the price of store bough ammo at 25 cents a round. So some folks have been experimenting with powder coating their own cast bullets in order to make their own "polymer plated" projectiles. Apparently in Europe you can buy them ready made like that. So the basic idea works. The fly in the ointment is how to roll your own consistently without a big powder coat gun setup. Some folks have been using the dry shake and bake method with varying degrees of success. Pop the projectiles in a plastic tub, add a couple of teaspoons of coating powder, cover and shake away. Pour them out on a tray and bake at 400 degrees F for twenty minutes.  So I figured what the heck lets give it a try.
A word with my friend Jonathan puts in an order for a discarded toaster oven from the Take-it-or-leave-it at the cape Elizabeth dump. Sure enough next day he calls back and provides us with the desired item. It was a bit nasty looking as if it had sat in someones garage for about 50 years. But after some elbow grease with some cleaner, a Scotch-Bright pad and paper towel the oven looks spick and span. A quick test and it seems in working order. As to actual temperature achieved I shall have to put an oven thermometer in it and see.
Five and a half dollars buys us some powder coat paint at the local Harbor-Freight
Some old soft lead .357 cowboy action round nose pills I had stashed away . . .
and some hard cast 157 grain .357 Semi Wad Cutters get washed in Xilol to remove all trace of oils.
Tossed with some powder and popped in the oven at 400 deg F for 20 minutes
And the results are promising but not the best and could really be improved upon. I think its a mater of technique.
Then I read that folks have had problems with the Harbor-Fright black powder and they had better luck with the red. So I bought a tub of that and gave it a try.
I re-tumble the soft lead round nose ones I originally coated in black along with some fresh hard cast SWC on the right in the pix and bake again. This time on parchment paper to prevent sticking to the aluminum foil.
The single coat SWCs are a bit better this time but could be improved.
The double coat soft lead round nose look more thoroughly coated this time but are still a bit lumpy. A sizing die should even them up a bit.
They definitely will need to be run through a sizing die as the .357 are now 360 thousands. I have yet to try loading or firing any of these. I think I need to experiment a bit with the method to improve results. Other folks are using a slurry method where they mix the powder with acetone and seem to be getting somewhat better adhesion. I think I will give that a try next.


4 comments:

  1. Interesting, go ahead! I remember when some 30 years ago I casted spheric bullets for my black powder 1860 Colt replica, I used to add to the 'pipe' lead some tin. It was obtained free from printers. I think it was done to reduce lead residues in the barrel; sorry, have no records of those bullets performance with regard reducing residues.

    ReplyDelete
    Replies
    1. Yes, to harden the lead you need to add some tin or antimony. If you use pure soft lead you foul the barrel. At slow speeds below 1200 feet per second that, and good bullet lube is usually enough to prevent lead fouling. Once you start getting in to faster modern high speed calibers that are moving at 3000 fps, jacketed or plated bullets are the only way to go. Essentially with the powdercoating we are making a polymer coated bullet but one that hopefully only costs a couple cents a piece, as opposed to 25 cents every time you squeeze the trigger.

      Delete
  2. I will be watching your experiments with interest. I have some lead bullets I bought for my .45 Long Colt reloads, but I have never cast my own bullets or anything of that nature. I just mostly buy Sierra or Hornaday bullets.

    ReplyDelete
    Replies
    1. Harry, the round nose soft lead ones were some store bought Magtechs that were basically a mistake purchase as they are far too soft for .357 speeds. Hopefully they'll make for a good experiment. If the powder coat keeps those soft ones from leading the barrel then the process should work for the harder cast ones as well. The SWC ones are home cast. I just need to refine the process on the shake and bake powder coating. Ambient moisture seems to play a role, so what works on one day might not work the next. There is definitely a learning curve to it, but for me that's the fun in it. I just got a .223 LEE mold and I am still waiting on a sizing die. Some time when things slow down for me in the winter I will play with it some more.

      Delete