Has anyone given thought to alloying normal bullet metals with hexagonal boron nitride.  I know that some people shot peen it to copper jacketed bullets.  It melts at 3000+ degrees Centigrade and at least theoretically should make a self lubricating bullet.   

Opinions welcome

or the best of all, the paper patched bullet
keep safe,
bruce.

If boron nitride melts at 3000+ degrees C, then it's not going to combine with the lead alloy mix. Since it's density will be different from the lead alloy it would probably either float on top of the mix or sink to the bottom of the mix. Either way it probably isn't going to form a solution so it won't be incorporated into the bullet.

Interesting stuff. However, I'm a bit concerned about having  something hard enough
to scratch diamond sliding down the bore of my rifle. Sounds too much like lapping. 
Nevertheless, it is used as a lubricant. Time and some careful experiments will tell. 

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Jeff Houck wrote on Dec 5^th, 2015 at 10:15am:


That's what I was wondering but then I was thinking that antimony which is in many alloys melts at 1167 degrees Fahrenheit.  Normal casting temperature usually doesn't exceed 800 or so degrees F. but we don't see visible chunks of antimony failing to melt in the pot.  Maybe its at the crystal lattice level.   

Additionally antimony is about 1/2 the molar mass of lead, so it is also significantly less dense that lead and about the same density as tin, neither of which we see settling out by density during the melt  so it would seem that there is some other process at work here for metals in the melt like antimony.   

Looking forward to more discussion. 

calledflyer wrote on Dec 5^th, 2015 at 12:52pm:


Good point - here's an article I found about the Department of Defense adding Hexagonal boron Nitride to their powder indicating that it might double bore life on a howitzers I believe  

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One article I read says that "it can be hydrolized in boiling water"  and as I remember from chemistry a long time ago hydrolysis is breaking down a molecule/compound.  If you can hydrolyze boron nitride by pumping boiling water through your barrel, you shoud be left with a clean barrel, water, boric acid, and ammonia I think, but now I need a chemist as well as a metallurgist.   

Still gonna skip it, hydrolizable (is that a word?) or not. By the time you pour water into a bore, it ain't boiling any longer.   
By the way now you need a metalurgist, chemist, and a hot water pump as well. Thanks, but no thanks.

After a year of metallurgy, Ill offer this since my final was a dissertation on PbSn alloys for improved bullet strength:

Pb and Sn are a solid solution, with regard to bullets.
Forget the idea of Antimony melting point at very high temps.
The Antimony you need to introduce is done at high temps and is always alloyed--- not at your home! You don't have the necessary STUFF to make lead and antimony marry.
Once married the Pb is a carrier of the antimony, thus Rotometals sells antimonial Lead! A way to get your antimony w/o the marital problems.

Solid solutions are different, they are not ionic/covalent bonded, its more like mixing salt and pepper. With heating and cooling the position of the antimony is controlled, I.e. whether Antimony is wrapping lead crystals or sitting in chunks here and there.
Using VERY non scientific terms here for sake of clarity.

You can control antimony position with a good deal of accuracy based on its cooling curve and start temps, just like you control steel's crystalline structure--- read up on conversion of ferritic iron/carbon to pearlite and conversion to martensite. Its all in how you heat and cool as to what the solid solution does. Water quench a bullet, heat treat a bullet, air cool a bullet, all control Antimonial Position directly!!!

Now I think you would be venturing into uncharted territory with adding boron Hex to lead, it would be considered an alloy, an inclusion (like carbon flecks in a diamond), it would alter the bullets brinell hardness and strength for a given alloy and may not enter a solution with either antimony, lead, tin, zinc, etc that may be also present in your bullet alloy, until maybe those materials are at vapor stages, meaning, you can't get boron suspended before your lead turns to a gas. I'm not a chemist. You can add crap till the cows come home but think what happens when you flux your bullet melt. You add WOOD, parafin, bees wax, carnuba, and various salts that float. That boron is AWFUL light and not soluble potentially and it won't change state (not hot enough to go from solid to liquid to gas) so........ FLOATS, TEMP, NON-SOLUBLE---- seems like its dead

Except when you coat the bullet. You don't want the boron in the bullet you want it at the surface.
Lee Liquid Alox, think coating, which is how boron is traditionally applied to bullets.
Ill bet a doughnut if you melt a boron coated bullet in your pot, the boron will flux off.
Impregnation, not solution is the key to use.

See ya