Bronzong has not been used by me, however in Ubers it walls a lot of shit, and let's not forget it can Hypnosis, Stealth Rock, Toxic, Light Screen/Reflect, ReStalk and Explosion, plus 76 Speed is like Death to all with Gyro Ball. Pressure's a bitch, though. All calculations are considering that you're max in that stat. Otherwise you should get out.
The Uber Walls
Lugia: Let's admit it, Lugia is as walled as Bronzong. Bronzong can Explode if neccessary, and/or put Lugia to sleep.
Giratina: If you're hit with a Critical Hit, Choice Banded Shadow Claw and you have Leftovers, it won't KO you unless it CHs again. It can also be put to Sleep
Deoxys-D: lol that's funny. Toxic Bronzong sounds nice right now. Or Hypnosis.
The Uber sweepers
Mewtwo: Choice Specs Mewtwo with Focus Blast/Thunder does 47-55%, in other words, it's walled.
Deoxys-A: 2HKOs with Focus Blast/Thunder, but otherwise can't get past you.
Rayquaza: Resists everything short of Overheat and other Fire moves, and only Overheat and Fire Blast even 2HKO.
Kyogre: Bronzong can't even joke with it.
Groudon: Most of the time has a Fire move, but non Swords Dancing ones are walled so badly.
Ho-oh: lol see Heatran
Palkia: If you're in the Sand you'll be 3HKOed.
Dialga: Can't hit you with anything but CS sets, and you can EarthQuake or put it to sleep.
Darkrai: ReStalking variations beat Darkrai BAD.
Latios and Latias: Most of the time you'll beat it by simply attacking.
Manaphy: WTF Manaphy?
Other Ubers
Arceus: Only certain types can face down Bronzong.
Mew: You'll beat non-BP variations.
Deoxys and Deoxys-S:
Non Uber Pokemon in ubers
Blissey: Blissey rarely has defense or has no HP in Ubers, it is 2HKOed.
Metagross: Can't get past you. Ever.
Heatran: lol see Ho-Oh
Tyranitar: Sets up valuable Sand for you. Nonetheless, you aren't going to beat it.
Heracross: No chance either.
Ninjask: Stealth Rock is set up, Gyro Ball OHKOs.
Skarmory: It's like Lugia.
Forretress: It's like Lugia.
Magnezone: No chance at beating this, unless you pack EarthQuake.
Weavile: Completely walled by you.
Shedinja: If you're using this with Sandstream it's dead lol. Stealth Rock, etc.
Jirachi: Walled by you, can be put to sleep as well.
I didn't include the other Weather bastards, they're quite irrellevent.
The Uber Walls
Lugia: Let's admit it, Lugia is as walled as Bronzong. Bronzong can Explode if neccessary, and/or put Lugia to sleep.
Giratina: If you're hit with a Critical Hit, Choice Banded Shadow Claw and you have Leftovers, it won't KO you unless it CHs again. It can also be put to Sleep
Deoxys-D: lol that's funny. Toxic Bronzong sounds nice right now. Or Hypnosis.
The Uber sweepers
Mewtwo: Choice Specs Mewtwo with Focus Blast/Thunder does 47-55%, in other words, it's walled.
Deoxys-A: 2HKOs with Focus Blast/Thunder, but otherwise can't get past you.
Rayquaza: Resists everything short of Overheat and other Fire moves, and only Overheat and Fire Blast even 2HKO.
Kyogre: Bronzong can't even joke with it.
Groudon: Most of the time has a Fire move, but non Swords Dancing ones are walled so badly.
Ho-oh: lol see Heatran
Palkia: If you're in the Sand you'll be 3HKOed.
Dialga: Can't hit you with anything but CS sets, and you can EarthQuake or put it to sleep.
Darkrai: ReStalking variations beat Darkrai BAD.
Latios and Latias: Most of the time you'll beat it by simply attacking.
Manaphy: WTF Manaphy?
Other Ubers
Arceus: Only certain types can face down Bronzong.
Mew: You'll beat non-BP variations.
Deoxys and Deoxys-S:
Non Uber Pokemon in ubers
Blissey: Blissey rarely has defense or has no HP in Ubers, it is 2HKOed.
Metagross: Can't get past you. Ever.
Heatran: lol see Ho-Oh
Tyranitar: Sets up valuable Sand for you. Nonetheless, you aren't going to beat it.
Heracross: No chance either.
Ninjask: Stealth Rock is set up, Gyro Ball OHKOs.
Skarmory: It's like Lugia.
Forretress: It's like Lugia.
Magnezone: No chance at beating this, unless you pack EarthQuake.
Weavile: Completely walled by you.
Shedinja: If you're using this with Sandstream it's dead lol. Stealth Rock, etc.
Jirachi: Walled by you, can be put to sleep as well.
I didn't include the other Weather bastards, they're quite irrellevent.