My favorite bulk 9mm bullet is the Rem. 124 gr. JHP. I have the Montana Gold 124 gr. JHPs and mine are about .001" under sized. ZERO's are better than the MG's IMO, but the Rem. 124 is one of the most consistently accurate bullets I've used in handloading the 9mm for 28 years. It has a tougher jacket and is a deep penetrator. To make it an excellent expander you'll need to use a good medium/slow powder. I use Silhouette and worked up to SIERRA's max. load level except I load mine at 1.122"/28.5mm which is a good bit longer than SIERRA loads their 125 gr. JHP to. This will cut down the distance for bullet jump into the bore and give you better accuracy. Ideally, you want to load specifically for the chamber length for your pistol and you can find several methods for doing that with the search function. If not, post and tell me and I'll explain how that's done.