Carry/deffensive ammo you want a Bonded jacketed hollow point, I like 124gr federal HST, Speer Golddot 124gr is also good, so is Winchester deffend.
Range ammo any brass cased ball ammo should function in your shield, I've never had any kind of failure in mine of any kind, I've always used 115gr, or 124gr have never tried running 147gr (maybe that's what your referring too as far as ammo finicky)
But yeah my MP has had 100% reliability with all ammo. And right now it's really about whatever ammo you can find, its in limited supply and expensive.
But you should have no issues with 115 and 124gr just make sure to clean and lube before the 1st range session.

Federal HST 124gr in stock here. This is the 9mm ammo most law enforcement/FBI carries it is proven to stop threats.
laxammo.com/federal-premium-le-9-mm-124-gr-hst-50-rds-p9hst1-detail
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Then range ammo any brass or nickel plated 115gr, or 124gr -----https://ammoseek.com/ammo/9mm-luger

Bernard, for home defense a 115gr thru 147gr Hollow Point Round would work just fine. I recommend these : topshelfammo.com/product/9mm-124-gr-jhp-self-defense-qty-50-10-box-limit/ -------------------- heritageammunition.com/product/new-brass-9mm-147gr-hhp/

Bernard, for home defense a 115gr or 124gr Hollow Point Round would work just fine. I recommend these : topshelfammo.com/product/9mm-124-gr-jhp-self-defense-qty-50-10-box-limit/ --------------------