I'd like to get into USPSA production but have one very important question that Google couldn't answer. I have a m&p40 which will have to be my competition gun but I run it with a s&w 9mm factory barrel (I don't want a discussion on if it works or not, I've used it for years on the range with great success). Since I want to run Production, can I use the 9mm barrel? Again, it is straight from the factory. I don't want to use .40 because power factor is null. Thanks