HbN coating, black copper

RTG22

Private
Minuteman
Mar 13, 2020
13
8
Hello fellow shooter,

I coat my bullets with hexagon boron nitride. Today I saw that the copper jackets (Lapua scenar l) turned black. I think the air was to moist and colored the copper black...I tried but I cannot rub it off with a towel or microfiber cloth.

Can I still use the bullets or can I better throw them away? I just coated 2/300 bullets that all turned black. 1000 bullets costs in Europe 460 usd, it it only where 50 bullets i would throw them away for sure.

Kind regards,
 

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Just shoot em. Looks like the coating reacted to the moisture in the air.
If you gotta have shiny jackets, try soaking them in water with a little citric acid solution.
 
just like copper but then dull like stained glass (left op picture, right is without coating).
 

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Just shoot em. Looks like the coating reacted to the moisture in the air.
If you gotta have shiny jackets, try soaking them in water with a little citric acid solution.

Thanks! I don’t care about the color, even if they where pink with purple dots. I only want the same accuracy and them not to wear my barrel More out than uncoated bullets,
 
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I use the David Tubb HBN kit and it works well.

Same thing happened to me when i left a 100 bullets in the plastic tumbling bottle for a few days without cleaning off the excess. Pretty sure it is the copper anti-fouling agent that Mr. Tubb adds (which i am pretty sure is also the source of the ammonia smell when you open the bottle after tumbling). The coated bullets all had dark blue / black corrosion marks on the copper jacket.

Rubbed the bullets down, then tumbled them a second time. They shot ok, same/similar speed and adequate accuracy. Speed of this batch was a little different (30 fps lower) compared to normal speed, but SD was good enough (9 fps).
 
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Only time i have had issues with HBN coated bullets not shooting well, was when i mixed the left-over twice tumbled (corroded) bullets mentioned above with correctly coated bullets (white milky color) in the same batch of hand-loaded ammo. SD went from 8 to 14.5 fps, and ES went straight up to 56 fps.

Did not shoot good groups that day. But this problem is easily avoided!
 
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Hello fellow shooter,

I coat my bullets with hexagon boron nitride. Today I saw that the copper jackets (Lapua scenar l) turned black. I think the air was to moist and colored the copper black...I tried but I cannot rub it off with a towel or microfiber cloth.

Can I still use the bullets or can I better throw them away? I just coated 2/300 bullets that all turned black. 1000 bullets costs in Europe 460 usd, it it only where 50 bullets i would throw them away for sure.

Kind regards,
How do you order the hex boron kit in Europe? Seems bullletcoating.com and Tubbs will not ship.
 
I don’t have the Tubbs kit, I just bought a jar of HbN. You can impact plate with steel BB’s or bearings, I even did it with stainless steel tumbling media (jewlers shot).

On eBay you can buy HbN from Microlubrol And a lot of other brands. Just search on HbN, If I search for hex’s boron nitride I don’t find it. Just look for the correct particle size. I personally use HbN from lower friction. It has a particle size of .50micron