Hello first time posting, I am milling some 4130 34 HRC. I am using a Helical 83108 .500 dia 2.0 LOC chip breaker endmill with a Schunk Hydraulic Holder using high efficiency milling running 3050 rpm and feed rate of 30 ipm with a 4% radial and full axial. Now these endmill are running for about 7 hours before they break at around 31% spindle load. Should I be expecting more? the helical website suggest I run the tools way faster like 8950 rpm at a feed of 72 with a 8% radial engagement. I am running in a HAAS UMC 750 15k Spindle BTW. I have a lot of these parts to make so any help would be appreciated