Putting two 3/16″ holes in a 1911 barrel for an open division race gun.
.125″ carbide 2 flute straight spot drill at 3050 RPM and 3.2IPM plunge
3″16″ ball end mill at 3000 RPM and 4 IPM plunge
Done on my CNC RF45 mill and programmed with HSMWorks.
Background commentary since my last time around I broke off a HSS twist drill in the barrel as the tip broke through.
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