It is easy to get slightly off topic and speak in 'generalizations' and from reading vaious forums and opinions that are not 'specific' to the question that has been asked here. Specifically, I own this marker and I own the 12, 14, and 16" J&J barrels and the Big Red Field Chrono. But even with these advantages I accept the fact on any given day with any given paintball with any given player that substantial variants do exist. I have personally tested the ProCarbine with the various lengths of J&J barrels and actually found no measurable chg in efficiency from one barrel to the next. I did not have to chg my fps settings as I moved from a 12 to 14 to 16" barrel. I kept the speed btween 275 and 285 easily. Accuracy was tight and as good as many much more expensive barrels. I am sure that slight differences could be detected under lab conditions but that is not where I play paintball. If you have the opportunity, compare the ProCarbine with various J&J barrels. Make your arguments specific. In this case, even with all the knowledge gleened form various forums, I highly recommend the ProCarbine / 16"J&J barrel combo for efficient, accurate and enjoyable paintball. If you study enough forums you will find that there are many experienced palyers that share my view on this particular setup.
Play hard, play safe, play smart

The best barrel I've found for my P.C. is a brass one from palmer's. Not cheap, but you can get it in any size you want and I have never had a problem with any paint. Also mine is unported, and with the home make loudner it very nice!

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