Plating Pistol Bullets

I run a small company that makes hard cast hand gun bullets for hunting and I would like to learn how to apply a copper plating to them to get rid of the problem of leading the bore. I need a process that will apply the copper to hundred's of bullets at a time and will not beat them up or distort them in anyway. Also it must be put on in a way that the plating won't strip off in the riflings of the bore under the extreme pressures of the bullet passing at high velocity. I know it can be done as another company does it to their bullets.

Thanks,

John Anderson
- Andalusia, Illinois

Match Grade 308's? I prefer 300 Mags on a windy day, and 25-06 on a hot calm day. I've shot those rounds and the Copper still comes off in the rifling. In order for the rifling to function it must gall the bullet surface, and in so doing some of the copper is transferred to the rifling lanes. You can analyze the cleaning patches for copper and find it there. Anyway I recommend barrel plating in a finer media such as BBs. If you are really concerned you can use a rotating kiln design. This would virtually eliminate any distortion of the surface, then screen separate them. Fluoborate process. I used to barrel plate Cadmium with a Chromate conversion coating onto 20mm rounds for the navy without media and they still shot as true as 20mm can shoot.

Dave Kinghorn
Chemical Engineer
SUNNYvale, California

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John,

Many years ago I worked at an ammunition company. They manufactured ammo of most common cals. They used a tumbler barrel plating process in very hot potassium cyanide plating solution. I remember the two main hassles they had,were with the antimony content of the lead, causing passivity during chemical cleaning. So be sure of that and work back. and the absolutely critical level of free cyanide in the copper strike bath. That's how they did it.

Mark Gunn
- NSW, Australia

February 11, 2009

Hi I am not a engineer but I have been experimenting with a small drum plating setup for my personal use on 45 acp and 45 70 with mixed results not having access to cyanide I have focused on an acid type plating bath ( copper sulfate sulfuric acid my plater handles around 400 rounds at a time and while not the best bullets I have seen it does turn out usable plated bullets the drum plater itself works great but I am not happy with the rest of the process but I am still learning . bonding to the lead is not what it should be and the plating is somewhat brittle. may try annealing after plating also I am casting from wheel weights, and other elements in the lead may be affecting the copper lead bond . also need to work on the pre plating preparation. my first batch I washed in sodium hydroxide solution and got very poor bonding; plain hot water worked much better, may try phosphoric acid wash next. I will email you pics of the plater if you wish it would be easy to scale up to a larger size if needed. don't be afraid to experiment!

mark dula
- stony point, North Carolina opt