I know that the blues scale is only 6 notes... Let's take the blues scale in the key of C for example: C - Eb - F - Gb - G - Bb - C

What I am thinking is that are there any other notes that you can use? The reason I ask is because sometimes when I integrate B in the scale it doesn't sound wrong. Is this just a dumb question?

is that a part of another similar scale?
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I dont know much theory, but I was in the same place as you a few months ago. I just concluded on 'if it works, why shouldnt I use it?'. If it sounds good to you, why should it matter if the theory says its wrong? (of course, it probably doesnt, but its hypothetical)
If it's "wrong" in theory, but it sounds good, use it! Theory is just a guideline, not what should and should not be.
B as the major seventh won't sound great on it's own over a C7, however, it can be used very well as a passing tone.

When playing 8th notes, it allows you to hit chord tones on downbeats: for instance: C-B-Bb-A-G-F-E-D-C, played as eights, allows each bolded chord tone to be played on a downbeat.

But really, there aren't any limits on the notes you can play: some are just easier to use. Here's my second article by beat in two days.... https://www.ultimate-guitar.com/forum/showthread.php?t=127995 I found it helpful.
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Thanks for all the responses...that was really fast too. I have thought about this for a long time actually, I asked my music teacher and she either didn't understand the question or just thought I was rambling... Either way, you guys cleared it up for me somewhat. Thanks again...hopefully I can get even more replies and clear it up further. Psyschodelia, I will read that article (although, I really don't know much about theory).
Now that I've though about it, B is the major third ( a chord tone) of G7, a chord in the C blues progression. You could hit lot's of Bs over that G7 chord. You could also use it as the blue note over the F7 chord.
Speaking of the major third, that's probably the most common out-of-scale note to hit. Its a real common blues thing to bend the b3 to major 3 when playing over the I chord.

Example: in key of C, take the Eb and bend it up to an E. Or in key of A, take the C and bend it up to C#.

(Some people even think the blues scale should include both the b3 and the major third, its used so often)

Of course, you have to be careful how you use it, in a standard blues, that technique may sound good over the I chord, but it won't sound that good over the IV or V chords, because of the notes contained within those chords.

Also it won't sound right if you're playing a minor blues (example: key of Cm, not C major)