Well.... what kind of paint are you using currently?

deadeye98 wrote: I've been having problems with my Flatline barrel..Everytime I shoot the ball always curves and goes everywhere..I know that the barrel is made to curve but I haven't shot one ball straight yet..I'm thinking that the balls are to big..What paint should I use.?.?

The Flatline works best with small to small-medium paint. The long standing paint of choice has been PMI Marballizer and All Star. Problem with these is expense ($55 to $70 a case). I have found that much less expensive paints such as Diablo Heat, Blaze and Draxxus Rec-Sport are working nearly a well (buying it from 888paintball.com for about $32 a case, freight for their 5 case special adds to the cost making each case average about $35 each).

Paint that is medium to large diameter, Nelson Hot Spot and Special Forces paint are ones with which which I've had some experience, tend to not roll smoothly against the curve of the barrel. Large diameter paint touches the barrel in several places during its trip from breech to muzzle. Since the Flatline is not smooth inside, it has a bead blasted internal finish, any touch imparts spin in that direction. This leads to erratic flight rather than the desired flat trajectory coveted with the Flatline.

Also, clean your barrel with hot soap and water to keep it working properly.

gslstar wrote:  I like marbs and Diablo heat. I'm going to try Draxxus nightmare. These are all considered small bore paints. There is a paint to barrel matching chart at http://www.ottersccustoms.com - www.ottersccustoms.com   The Flatline is a .692 which means the barrel actually measures that big, so a ball that measures .687-.689 is small enough to get back spun in the barrel.  If everything is working well, it'll come out and fly a pretty flat trajectory. It's not always dead accurate for me but it seems very predictable. I've tried a j&j ceramic next to the Flatline and they compare fairly well but, the Flatline definitely will go flatter farther.

But, if you measure the Flatline in its curved section you will find it is slightly oval shaped. So strictly speaking saying it is .692" isn't really accurate. In the oval shape the sidewalls are slightly closer than they would be if if the bore were round. It takes a smaller ball to really get into the "groove" of the barrel.

Barrels vary slightly so you may get good performance with a ball as large as .689" but that hasn't been my experience. After trying PMI Marballizer and All Star I found that smaller, and less expensive, paint like Diablo Heat really works well. And regardless of what the charts say, I size my paint and Heat is always, lot to lot, order after order, .683".

duffer1497 wrote: 888paintball.com is the way to go i use diablo paint ALL brands i have no problems shooting straight plus the deal @ 888paintball is great

I mentioned Heat becaust that is the paint you get for the 5 case special (sometimes they substitute Blaze or Rec-Sport which usually work well also).

gslstar wrote: I agree with Frank about the heat It has shot pretty well. I just tried the diablo nightmare and it was o.k. I didn't know that the flatline barrell is oval shaped, I got the measurements from a barrel chart. Sorry for any confusion.

It requires a set of good calipers to detect it. The tube is obviously bent in a forming dye and to compensate for the tendency to flatten when bent the dye conforms the tube to an ever so slightly oval shape. Just the normal bending process.