I would start with 1-2 boxes of all the major brands. Figure out what your M-9 likes the best and then buy a case.
When it comes to ball ammo I am never really picky. in 9mm I purchase the foreign stuff like PMP or MFS as it is cheap and just for plinking.
.40 cal I buy PMC as it is a bit lower recoil and competative in price.
.45 I buy the absolute least expensive I can find.
I do stay away from the Russian steel cased ammo as I think it rougher on extractors. The only guns I shoot steel case in are an AK,SKS or Makarov.
When it comes to ball ammo I am never really picky. in 9mm I purchase the foreign stuff like PMP or MFS as it is cheap and just for plinking.
.40 cal I buy PMC as it is a bit lower recoil and competative in price.
.45 I buy the absolute least expensive I can find.
I do stay away from the Russian steel cased ammo as I think it rougher on extractors. The only guns I shoot steel case in are an AK,SKS or Makarov.