Radically Invasive Projectile - RIP - in 50 BMG Calibre

I am not a true expert on machining copper - not stupid, limited experience, basic stuff - drilling and tapping holes etc. I don't have much call to make any thing from copper... I have made a few small things like a copper head for a soddering iron - that I also made, and one or two other things that it was NOT worth tooling up for... It's NOT worth doing an exact drill cutting angle and materials, and surface treatments, for one or two holes.. It's not worth getting a tap, with the optimised materials and cutting angles and clearances for ONE hole..... AND it's not worth buying a BIG tin or container of cutting fluid, specifically designed, for drilling and tapping ONE hole in copper.....

And copper just gums up and binds - so badly...

So copper is an absolutely LOVELY metal... Fuck it's gorgeous.. But it is an absolute cunt to with....

It's the maching equivalent of stirring rapidly cooling hard toffee in a water cooled bowl, with a wooden spoon....

The spoon will glue into the hardening mass of toffee and the handle will just snap clean off the spoon, rather than stir or pull out.

It's fucking unbelievable...

I am sure of it, that I could of done it a lot better, using specialist copper cutting profiles in the machining tools, special lubricants etc.. BUT I only wanted ONE threaded 6mm hole, in a small copper head for a soldering iron...

But tapping and drilling holes in COPPER, with conventional drills and taps, is a "glue" the drills and taps - seized HARD, into the holes.....

LOW RPM, Light Feed Rate - Drill in 2mm lubricate the hole, pull out, lubricate the hole, drill 2mm, lubricate, pull out, lubricate, etc., get 8mm into a 12mm hole and the drill LOCKS into the hole and the drill snaps off....

Taps run in 2 turns, back the tap out, lubricate, tap 4 turns in, back the tap out, lubricate, tap 6 turns in, back the tap out, lubricate...

The tap WELDS locked in solid, and won't back out - but the tap will snap, rather than back out...

So he probably had specially profiled cutter teeth and lubricants and all that, to make these bullets... OR he knew someone who did..

Copper is very very soft... but FUCK it's hard to machine...

Who ever has made the COPPER bullet, as used in the starter image, has had all the right tools, especially set up for copper, with the cutting fluid for copper, with the indexing and CNC machinery to get it all done, exactly so.....

And that bullet design, the machining on it, that is a beautiful piece of work......


https://en.wikipedia.org/wiki/Copper

Pure copper's ductility, weakness and high friction between copper chips and cutting tools makes machining of copper difficult; alloys are preferred for good machinability.[175]

https://link.springer.com/rwe/....10.1007/978-1-4471-4

JEW-GLE - Ai data harvesting.

Machining copper requires specific tooling and lubrication profiles to counteract its softness, gumminess, and high thermal conductivity. The primary goal is to cleanly shear the material rather than push or smear it, which prevents the copper from adhering to the cutting edge and causing a built-up edge.

Cutting Tool ProfilesTo achieve clean cuts and extend tool life, copper requires tools with highly specific geometries and materials.

Tool Material: Use uncoated, polished carbide or diamond-coated (PCD) tools.

Standard hard coatings (like TiAlN) should be avoided on pure copper, as they can increase friction and induce material adhesion.

Rake Angle: A high positive rake angle (between 15 degrees to 25 degrees) provides a razor-sharp edge that slices the material cleanly rather than pushing it.

Clearance/Relief Angle: Generous clearance angles (around 12 degrees to 15 degrees) are necessary to prevent the tool flank from rubbing against the workpiece and generating friction-based heat.

Edge Preparation: The cutting edge must be dead sharp and highly polished. Any honing or dulling will cause the copper to smear rather than cut.

Helix Angle: Variable or high-helix end mills (between 30 degrees and 45 degrees) are highly effective for copper, as they promote continuous, stable chip flow and prevent the material from packing into the flutes.

Flute Count: For milling, opt for 2- or 3-flute end mills, which provide a larger chip evacuation space compared to 4-flute designs, reducing the chance of recutting chips.

Lubrication & Coolant ProfilesBecause copper is highly ductile and conducts heat rapidly, an ideal lubricant needs extreme pressure (EP) properties to reduce friction while keeping the cutting zone properly cooled.

Type of Fluid: Use neat cutting oils or silica-based/synthetic water-soluble coolants mixed to a milk-like viscosity.Extreme Pressure (EP) Additives: The fluid should be formulated with inactive sulfur or fatty-based additives (such as lard oil formulations) to prevent the copper from chemically bonding to the tool.

Application: Flood coolant or through-spindle coolant is recommended to simultaneously lubricate the cut and evacuate heat.

Chip Management: A strong air blast or coolant mist should be used alongside the lubricant to clear chips immediately.

Copper chips are highly prone to scratching the workpiece and binding the tool if allowed to remain in the cut path.

Recommended resources for machining copper include the Harvey Performance Company catalog for tool selection, Grainger Canada for lubricants, and the Fictiv guide for material specifications.

These tools help identify specific cutting tools, compatible fluids, and engineering breakdowns of copper grades.


https://www.grainger.ca/en/cat....egory/cutting-oils-a

https://www.fictiv.com/article....s/copper-cnc-machini

Technically - These are brilliant - in some ways, for some thing.

But fuck.... Sometimes savagery is necessary.

However, some days I'd like to see a lot less of it.