a few questions 1st. What kind of a ml is it. There are co2 dischargers for side hammers, for something with a breech plug you can take out the plug and push the charge and bullet on threw. As far as how long when I 1st started I went hunting I left a charge in after a weekend hunt for around 3 weeks, it went bang and hit the bull, I don't do it as a every day thing but I leave the charge in while hunting unless the weather is lousy then i sort of play it by ear. This last year ml hunting indiana, hunted a day and a half in rain, it went bang and hit what I was aiming at.