I'm repairing a 257312 Lyman meehanite bullet mould. Used a
mechanic's length LH 135 degree point drill to back out the snapped off
HP pin retainer. Now its time to replace the hollow point pin that
extends into the bullet cavity.
Aluminum is out: markedly different expansion rate, scratches easier,
and bends easier. But molten lead does not stick to it at all. Pity...
This alloy must be able to take a fine finish. No 1018 CRS need apply.
Temperatures will be in the range of 725-800 Fahrenheit.
My first guess is HHS drill blanks. Also considering TGP.
The HP hole is a teeny bit bigger than a #41 drill (0.096 in/2.438 mm).
My small hole gauge set only goes down to 1/8"...
- posted 10 years ago