Does anyone know what it is?

[OtakuDemonKitten]

There is a show that was on TV a while ago and I'm not even sure if it was Anime or not but it was about a group of kids that shot these tube things out of guns and the tubes spin really fast and when they hit each other they release monsters and then the monsters battle, I tried looking it up but that's all I know about it.

[PictureGuy]

I assume you are not thinking of Pokemon.

[Anime Forum]

Probably Beyblade or Bakugan I'd assume!

[.:neuko:.]

Well I don't know any monster-battle-orientated anime besides Pokemon, Digimon and Yu-Gi-Oh! so this might be a long shot. Chances are you've heard of what I'm going to suggest since it isn't exactly obscure, and from what I can tell, is still running; but for what it's worth: Slugterra very strongly springs to mind. It sort of has anime-style characters (imo), though actually it's a Canadian-animated show and CG-rendered. The main character is about 15 years old and his friends seem to be mostly young teenagers, so I guess you could call them kids. They all carry weapons that resemble guns, though technically they're called Blasters. The "ammo" for these Blasters would be called slugs, which are loaded into small tubes before they are launched at high velocity against other slugs, which are launched by opponents in the same manner. Once a slug is airborne it will spin rapidly and then transform into what you could call a monster (technically Velocimorph), though nothing as large as say, a typical Pokemon - but otherwise it is monstrous in its capacity for destruction. There are also blasters that can launch pairs of slugs at a time. Once airborne they will spin rapidly and fuse into more powerful slugs, which again, sounds similar to your description.

[PictureGuy]

Canadian? It does not sound like SCTV.

[La Féline]

Well I don't know any monster-battle-orientated anime besides Pokemon, Digimon and Yu-Gi-Oh! so this might be a long shot. Chances are you've heard of what I'm going to suggest since it isn't exactly obscure, and from what I can tell, is still running; but for what it's worth: Slugterra very strongly springs to mind. It sort of has anime-style characters (imo), though actually it's a Canadian-animated show and CG-rendered. The main character is about 15 years old and his friends seem to be mostly young teenagers, so I guess you could call them kids. They all carry weapons that resemble guns, though technically they're called Blasters. The "ammo" for these Blasters would be called slugs, which are loaded into small tubes before they are launched at high velocity against other slugs, which are launched by opponents in the same manner. Once a slug is airborne it will spin rapidly and then transform into what you could call a monster (technically Velocimorph), though nothing as large as say, a typical Pokemon - but otherwise it is monstrous in its capacity for destruction. There are also blasters that can launch pairs of slugs at a time. Once airborne they will spin rapidly and fuse into more powerful slugs, which again, sounds similar to your description.

I admire your knowledge of Slugterra, a show i discovered when munching at 3 or so am, when they unlocked the CHRGD channel for the holidays. Given the description in OP, it was also my recommendation.