Read the RNS. HH says it in black and white. The recent SP movement gave too good an opportunity to pass up. Cash is king and to add growth and value to the company is gold dust.
Huge volume now. If the SP goes back above the placing then it will be a good decision. I don't see why it won't with current sentiment.
There is no reason for a company to be listed on AIM except to fund their operations. The anger at fund raising is absurd. Investing in AIM is mostly about having the stomach to sit with your investments in the red until it comes good. If they don't come good then so be it. Try somewhere else but don't get angry about fundraising and if you don't have the capital to absorb losses then put it in an index tracker or fund.
Let me guess you bought GUN based on nothing but ramping posts, did no research, and expected to make 50% in one day. You have noone to blame but yourself. Don't blame a company because you can't get something for free.