No, you do not need to load the ammo any different than you would for your 1911. Your standard taper crimp -.472 -.473 - should be fine.
You should make sure that all the cases have the primers seated correctly. The MAC fires from an open bolt with a fixed firing pin and a high primer might ignite prematurely.
I use 185 and 200 gr. SWCs loaded to light target -675 fps -velocities almost exclusively with flawless feeding.
Saves lead and produces less recoil for newer/smaller shooters. The MAC seems to eat anything and it has a big appetite.
Since you mention not having been around automatics before, and you are shooting a buddy's gun, I'll just throw in two quick pieces of advice.
1. 'If in doubt, check it out'.
When automatics (or semis for that matter) stop firing, never assume the gun is either empty or clear to resume fire.
If you have a stoppage, it was for a reason. Find out why.
Remove the magazine and cock the gun to inspect the chamber condition while at the same time noting if an empty case was extracted. The bolt on a MAC will remain forward on an empty magazine - no hold open.
If rounds are remaining in the magazine, and only after the chamber has been cleared, inspect the barrel to ensure that a bullet is not lodged in the barrel.
I have seen guns with bulged barrels from this lack of caution.
2. Try not to enjoy yourself TOO much. Your wallet will thank you.
Have fun blasting with the Brick, JT