If you've got Chrome you could try this:
Visit
Code:
https://twitter.com/search?l=&q=%23[YOUR HASHTAG HERE]&src=typd&lang=en-gb
Press F12, and make sure 'console' is chosen from the tabs at the top. Copy and paste this into the console and press enter:
Code:
var foo = ''; $(".username").each(function() { foo += $(this).text() + "," }); foo;
Copy and paste the results.
Note this will only get you what's on the screen, so scroll down until you've got everything you want.