Let's play name that rare no longer produced .338 projectile!!!

[d1ce]

Underwater cavitation bullet?

 

[trevj]

only way you could get a turned projectile to be accurate all the time would be if the machine was in perfect shape, you replaced the cutter after each projectile made, and somehow had a way to accurately measure the the Um the tool nose so it would cut the next one exactly the same. just not possible yet with today's machines that would make producing projectiles cost effective.

ways that can help would be tooling with liquid nitrogen traveling through it to keep it cold. it should also keep the part cool as it would freeze the chip as soon as it was cut. that would help with the tool life, but brass/copper is REALLY hard to turn, it acts a lot like plastic and is oddly very hard on tools for how soft it is.

Neither of the suggestions you make would be conducive to repeat performance of a machine tool.

Each time you replace the tool, you have to compensate for differences from the last tool. Liquid Nitrogen through the tool is being done, but in this case, it would add yet another complexity to trying to make the 'sameness' that is required to produce a consistent product. It would require, I think, a feedback system to adjust the flow to maintain the temperature the same under all cut conditions, else the tool tip would be continuously moving back and forth as the cut conditions changed. Enough to make a difference to us? Maybe not, but it sure would add a bunch of complexity to the machine. Probably best saved for machining processes that need it. Add too, the cost of liquid nitrogen. Another input expense.

The particular alloy to be used will dictate the ease or difficulty that is encountered, as well as dictate the cut path strategy. If you wanted bullets of Aluminum bronze, you would be facing a very different cut condition than if you wanted pure copper or Nickel-Al-bronze, or cartridge brass or leaded brass(dead easy to machine).

I suspect that the way to a consistent produce is to tool up to produce as accurate a product as you can, then automate the sorting to build batches of a particular weight or diameter, then run the bullets through a sizing die to produce a round, to size, bullet.

The real problem seems to be that folks that have the money and talents to do such projects, are busy making their money doing things that do not have so many headaches attached.

The returns do not seem to be there to convince folks to invest the amounts that they must, in precision capable machining equipment, to convince them to stay in the bullet game.



Cheers
Trev