Recently I was browsing through youtube and wikipedia when I chanced upon a branch of Japanese koryu bujutsu (ancient martial skill) that utilizes firearms known as Hojutsu(砲術). AFAIK the firearms used by hojutsu are as 'teppo',which are arquebuses derived from Portuguese models.
Basically the few well-known Hojutsu schools are Morishige-ryu(森重流砲術),Seki-ryu(関流砲術) & Yo-ryu(陽流砲術):
http://www.youtube.com/watch?v=3b6fwFG1ITM
http://www.youtube.com/watch?v=mpiAKkjplU8
http://www.youtube.com/watch?v=fQU17CkmAQg

Now,considering that the Chinese was the first to use firearms in war, had firearm in any form ever been part of Chinese Martial Arts?

I can't honestly comment on ancient China, but I know the internal art of Xingyi (Hsing-I) was taught to an attachment of Chinese soldiers during the Sino-Japanese War. The instructors adapted Xingyi spear forms for rifles armed with bayonets.

The guy aimed and shot a gun. I don't consider that to be part of martial arts. It is a ryu simply b/c no one know how to shoot back then and those who did are consider to be masters. Like I don't consider shooting a bow really really good martial art. It is martial, but not martial art b/c we already gave martial art some specific meanings.

In the broadest of definitions, it really is a martial art, or at least a discipline.

However, it is not a martial art in the popular sense that people typically envision martial arts as dealing with hand to hand or unarmed combat. More specific terms for disciplines involving ranged weapons would simply be "Archery" and "Gunnery"; which is why we use those terms instead of referring to them as "Martial Arts". Aside from the ritualization, if we boil down hojutsu, it is merely the firing of a gun; this is a discipline that existed in every gun-using state of old.

I have a question: by "we already gave martial art some specific meanings" whom do you mean by 'we'?
And it is pretty much inaccurate to think that "no one know how to shoot back then", western firearms had arrived in Japan in 1543, and by 1560 it was pretty much in use by warring states in Japan. AFAIK Prior to its arrival the Japan daimyos had tried to integrate Chinese firearm,but favoured the western ones after its arrival.


Fair enough I guess.

It might not be pretty, it might not be romantic, but it kills people. An that's what the martial arts are about.

Maybe we could re-phrase the question like this: Have any treatises on chinese gun-drills survived? Something from the Manchu dynasty maybe? The manchu did use plenty of guns I believe.

It's strange because even though japanese used firearms a lot (by the end of the 16th century, Japan counted more rifles per inhabitants than all other country in Europe and the rest of the world), it was more or less disgraceful for a samurai to shoot with such weapons. That's why "ashigaru", low-class soldiers (majority of the soldiers in battles), were the one to use it.

You should watch again the great Kuroswa's film "Kagemusha", there's a scene in it where an ashigaru using a rifle is aked by Ieyasau and other lords from the clan to show them how he proceed.

Funny to think also, that Tokugawa Ieyasu, the last of the three founders of Japan, totally banned rifles from Japan in the early 17th. Firearms only reappeared during the Meiji period.
This martial art, or however you want to call it, must surely come from that period.