Blue point/ Ingersoll impact

[Jake40]

I have a Blue Point at321 impact and I was wondering how often it needs greased threw the zirk on the back of the unit? When I first got it on trade it would make a squeal noise when you let off the trigger so I put a little grease in it and the noise has been gone ever since but I didn't know if there was a schedule to follow for greasing it?

 

[3 Gun Shooter]

If you are in the trade a shot once a month, home guy, a shot twice a year.