In Reply to: Need help with Mares pneumatic speargun operation posted by Robert Lee on July 30, 2008 at 18:35:54:

I was always fighting the same problem with mine... The problem is probably salt and corrosion built up in the end around the piston. I'd flush it with some kind of spray penetrating oil and clean it out then try to cock it by putting the spear tip against a solid surface and pushing on the gun for better leverage. Once you break it loose then its usually OK. I was always pumping mine up to the max since it looses pressure with depth and slows the spear down. I eventually figured out it was more of a curiosity than a practical speargun. Good luck!