This may be a stupid question but can you help me understand why some .22 ammo is cleaner shooting then others? For background, I have a SigSauer Mosquito that I really enjoy shooting. Sadly this gun is a real picky eater and only consistently shoots CCI Mini-Mag HP High-Velocity ammo. This stuff costs more then any other .22 ammo I've seen and is becoming increasingly hard to find. Now I could ask what other stuff would be just as good but I want to understand why the CCI rounds are better and what should I look for in other .22 ammo. Is it a function of it being 'high-velocity'? Is it more about the grain? I noticed the CCI stuff is 36 grain and most others I've seen are 40. What's the deal? Thanks!