There was a thread on here somewhere with a poster talking about the battery-powered guns, with good things to say about them.
All the epoxies that I have used come in a double tube with a mixing nozzle. Each manufacturer has it's own proprietary gun to install their product. I have used Simpson, Hilti, Epcon, and have the guns for each because different structural engineers spec different products. All the guns are $100 or more and the little single use mixing nozzles will bust the budget if you have to use very many of them. The sika I have used as two part cans mixed by hand, is this what you are putting in a standard caulkin gun. Whatever you are using heating will help.