Missed this question and I have experience with it. First off - DON'T DO IT on a Firehawk if you hunt anywhere where moisture could be a problem. The 209 holder has slots in it that allow the 'extra' flame to vent outside the touch hole. These are an open path from the environment to the powder. I used 209s in mine for 2 years while trying various ways to keep my powder dry and failed. I used the velcro sleeve that T/C sells and duct tape on the outside, rubber sleeves that I made to fit over the 209 holder, tiny O-rings under the primer and found that it was fruitless. Every time i hunted in the drizzle, rain, snow my Firehawk would hangfire or poop-fire. So now I back to #11 mag caps and loose powder and it works perfectly every time. I had changed to musket caps part way through my career with the Firehawk to deal with pellets and that was the start of all my problems. #11s are a little weak for pellets, musket caps are fine but they don't seal nearly as well, 209 don't seal at all. If you use loose powder and #11 mag caps all is well. My opinion...from my experiences....
