tweaks needed to use Flatline??

Yet ANOTHER Flatline thread 
I'm sorry if this has been covered, but I'm having problems with the search feature.
I realize there is another thread just below this which I think was a very similar question, but it seems to be helplessly adrift talking about "snipers" and e-grips.

What kinds of modifications and adjustments need to be made to ensure the right velocity is maintained and the Flatline performs at its full potential.
I've read that they can be the greatest thing since sliced bread or absolutely worthless depending on how your gun is tuned. I really like the thought of not having to arc my shots, but want to weigh the costs of having that ability.

I kinda want one (Flatline), but just bought a Lapco Bigshot (shipped today); Should I even bother with the Flatline before I'm ready to dump some more coin (in addition to the bbl) into this gun?

Also, just how important is finding the right paint to its performance?
From what I can tell, most places around here make you use their paint for "safety" reasons - I can only find one place that lets you bring your own.




Edited by EastSideRich - 28 May 2008 at 7:58pm

I never recommend the F/L as someone's only after-market barrel.  My advice would be to get a J&J or Lapco first, then get a F/L later.  The reason I give this advice despite being a fan of the F/L barrel is that I do not consider it a general purpose barrel; I think of it as more of a specialty barrel which is useful for certain situations such as long range suppressive fire or engaging the opposition in areas with limited firing lanes due to the local foliage.

I also recommend that anyone considering purchasing a F/L or an Apex try both of them out, if possible, before purchase.  These barrels seem to be items that people either love or hate with very little middle ground.  Additionally, many people really like one of the barrels and hate the other one.  (I happen to like F/Ls and detest Apexs.) 

With all that said, here is a short F/L primer:

• Overview. 
  
• A5/X7 installation is fairly easy.
• 98 installation is slightly more challenging.  (At least with the old F/L system--I have no experience with the new system.)
• Proper installation is vital to correct operation.  (The issues below generally relate to the 98 F/L much more than the others.)
  
• The barrel must be installed so that the arch of the barrel is perfectly lined up with the chamber/body of the marker.
• Failing to do so results in an "off-center" spin which can pull the ball off target to the left/right while it is imparting the lift that provides the flat trajectory.
• The barrel must be firmly seated in the marker.
• Failing to do so can result in pressure loss and inadequate velocity.
• Proper maintenance/upkeep is required.
• Any paint in a F/L barrel will result in wildly inaccurate shots.
• A good heavy duty squeegee on the field is a must unless you want your game to essentially end with the first barrel break.  (A rag for cleaning the squeegee is a good idea as well.)
• A second thorough cleaning after any game in which a break occurred is also a very good idea for maintaining optimum performance.
• For this cleaning I run a pull through squeegee through it several times (wiped clean between passes) followed by either a cloth patch or a "fluffy" polishing squeegee.
  
• This is also a good time to clean any paint out of the chamber, off of the bolt, out of the hopper, etc.  Any of this excess paint that gets into the barrel later will have a much more detrimental effect on F/L accuracy than it would with a normal barrel.
• Even without breaks, paint shell residue can build up on the friction surface inside the F/L barrel.  It is near impossible to remove with a squeegee and can significantly decrease the amount of spin put on the ball as it collects.
• About once a month I would soak my 98 F/L in hot soapy water for an hour or so to get rid of this.  (Dawn dishwashing liquid seems to work well.)
• Since I am to lazy to take apart my A5 F/L every time I need to do this I have just been pouring boiling water down the barrel and following it with a good squeegeeing.  So far, this seems to do the job.
• Paint selection is very important with this barrel.
• Small bored paints that can roll through the barrel unimpeded are the best selection.
• Extremely brittle paints are a poor choice.  When the paintball hits the "ramp" at the beginning of the barrel after leaving the chamber it abruptly changes direction approximately 30 degrees by hitting a metal surface.  This can be hard on the ball so the shell thicknesses preferred by speedball players can cause problems at this location.
• Fresh paint is a must.  Any dimpling, leaking, sweating, etc. can change the aerodynamics of the paintball and interfere with its intended flight path.
  
• Proper tuning is required for correct operation.
• Velocity is the most important factor.
• The 98 series F/L seems to work best at velocities between 270 and 280 fps.
• A5 F/Ls seem to prefer velocities in the lower 260s.
• Experimentation is required to find what each barrel prefers as they all seem to differ slightly and it can change when paint types or weather changes.
• Obviously, since velocity is so important to accuracy, the ability to shoot at a consistent velocity is a significant factor in F/L accuracy.
• Compressed air is quite useful for this.
• A regulator would increase delivery pressure consistency even more, but my experience is that the additional accuracy gain does not justify the cost.
• I tried a F/L with a low pressure kit and was unimpressed with the results.
• CO2 can be adequate for use with a F/L under the following conditions:
• Play is limited to warm weather.
• An expansion chamber is utilized to promote liquid CO2 evaporation.
• Other considerations:
• Since paint condition is of such importance to F/L operations, a hopper which is easy on paint is a must
• Weather.
• The operating dynamics of the F/L barrel system tend to magnify the problems related to paintball breakage in cold weather.  I don't even try to use mine when it gets below 60 degrees F.
• Heavy winds interfere with the F/L effect which provides the flat trajectory.  Most people only have to play one game with an F/L in high winds before they switch markers/barrels.
• Humidity can make the paintballs swell which can result in ineffective operation as well.
  
• Rapid fire.
• I have used both E-grips and Response Triggers (R/T) with F/L barrels and have had the best results with basic mechanical semi-auto fire.
• The F/L design results in it being an extremely inefficient barrel. 
  
• The "loose bore fit" required to allow spin allows air to "blow by" the ball.
• The friction surface which imparts the spin also provides extra resistance which must be overcome.
  
• It requires more air to achieve the 260 to 280 fps that the various F/Ls prefer than it takes for most barrels to launch a ball in excess of 300 fps.
• This means that with R/Ts air starvation can occur which results in decreased velocity, loss of R/T capability, or stoppages.
• Even if none of this occurs, the velocity changes that result from decreasing air pressure significantly affect accuracy.
• A fast rate of fire with an E-grip can have the same results.
• F/L utilization.
• Proper firing position is important.  The marker must be held so that it is perpendicular to the ground.  (In other words, hold the marker level with no tilt to either side.)  Failing to hold it level will result in the spin being incorrectly placed on the ball and will have the same result as if the barrel was not installed straight; the ball will pull to the right or left.  (Amount of inaccuracy will be proportional to amount of tilt.)
• An experienced F/L user can use this characteristic to put a small amount of controlled curve on their shots.
• Engaging opponents.
  
• I have had the best results with a steady and continuous series of 3 to 6 round bursts fired on semi-auto.  (This is especially effective at "suppression" ranges where the opponents shots are coming in on the bounce while the F/L rounds are still airborne on a horizontal trajectory.)
• At shorter ranges, a smart player will position him/herself to take advantage of the benefits provided by the F/L barrel.  (An example would be using overhead cover to break up incoming lobbed shots while being able to directly engage the opponents who are firing them.
• Ultra-fine tuning a F/L.  (For those who are really picky and have a lot of time on their hands.  I did this to a 98 Custom, but many of the steps can be used with other Tippmanns.  I like the reduced maintenance required by my A5 F/L but I still miss the way this one shot and regret getting rid of it.)
• Compressed air--for consistency.
• Expansion chamber
• This was a used old style expansion chamber that was actually more the equivalent of a gas-through grip.
• It provided a reservoir of air to help prevent air starvation in a manner similar to what low pressure chambers do on newer markers.
• Heavy duty spring from Maddmann spring kit and a tournament locking rear velocity adjuster.
• Used in conjunction with each other to provide additional tension on the hammer.
• Caused the hammer to hit the valve harder; opening it farther and for a longer time so more air was released with each shot.
• Used the forward velocity adjuster to restrict the airflow so that the air was released over a longer period of time.
• This resulted in the ball hitting the "ramp" at the beginning of the F/L barrel at a relatively slower velocity, then continuing to accelerate after it was in the barrel as the pressure behind it continued to build.
• A lot of trial and error went into getting the two velocity adjusters tuned correctly.  (Almost an entire season of play.)
• Ensured the barrel was positioned perfectly on the marker.  (Not an issue on the A5/X7 F/Ls; which is why I now have an A5 F/L rather than a 98 one.)
• Leveled the marker with a level and clamps.
• Experimented until barrel was in best position then marked the barrel, adapter and marker to ensure I could easily replicate the barrel installation.
• Practiced shooting it until I automatically held it level every time.
• Installed a cheap red dot from Wal-Mart and sighted it in at about 60 feet.
• Results:
• I did this initially just to prove to a friend that I could make a F/L accurate.  (Everyone said they weren't at the time.) 
  
• I succeeded; it would match my J&J (on another 98) out to about 50 feet and out shot it for about 30 feet after that (because of the inaccuracies inherent in lobbing and hoping.)  Beyond that, it was still quite accurate, but which one was better was dependent upon other factors such as terrain and situation.
• The bench test results were 10/10 on the head of a man-size silhouette at 50 feet (under perfect condition).
  
• It was respected to the point where some people referred to it as "the magic flatline."
  
• I increased and delayed the airflow release in hopes that I could make the marker easier on paint.  This worked as well; during one period I played for over two years without a break in this marker.
• The downside.
• The amount of air used (and wasted) for each shot made for a very loud marker.  Other names my friends had for it were "the cannon" and "the shotgun."  When I fired it, everyone on the field knew who I was and where I was.
• It was amazingly inefficient.  I got just under 400 shots out of a 68 cu. in. 3000 psi tank.
• It required constant tinkering/adjustment to maintain this level of performance.  (Another reason I said "heck with it" and traded it off.)
  

Just wanted to say one more time:

Thank you Mack.

Fantastic info.