Ugh another Flatline thread

Ok, so I know there are probably hundreds of threads regarding flatlines/apex barrel systems, but hopefully this will be a new twist. From everything I read, both offer an extra 100 or so feet over other non backspin barrels, but with the increased distance comes less accuracy and chances of paint breakage. My question is how accurate are these barrels at comparable ranges to non-backspin (NB) barrels (100-200ft)? Would it be safe to say that these are still superior over NB barrels becuase you get better 'flatline" accuracy? What I am getting at is, rather than having to arc shots, you can actually aim flat at objects within normal ranges. Rather than trying to use the FL/apex to reach the guy 300 feet away and "snipe", would it be a more useful tool to be able to aim directly at someone 200feet away versus having to arc up and lob? Basically shooting "through" someone rather than lobbing balls on top of them? Not sure how clear I am being. Any thoughts, or has this subject been beaten to death?

Edited by oldpbnoob - 28 May 2008 at 11:59am

At close range there is no discernible difference.  Beyond that, it must be kept in mind that the spin added to the ball is one more factor that complicates the interaction between the ball and the air it is traveling through. 

If, for instance, the gun was not held perfectly vertical when the shot was fired, then the spin would not be imparted perfectly vertical to the axis of the ball in relation to the ground.  This slight "off-center" spin would still provide the "Flatline effect," but would also be pulling the ball slightly to the side.  At shorter ranges this would have a negligible affect on accuracy, but this effect would increase proportionally in relation to the distance the ball traveled.

Cross-winds tend to affect balls fired from a backspin barrel more than those fired from traditional barrels as well.  The effect of the cross-wind is similar to holding the gun so it is not vertical as they also alter the direction/angle at which the wind resistance strikes the ball.  With a ball fired from a normal barrel, a cross-wind will generally alter the path of the projectile in a fairly predictable way that allows the user to compensate as necessary.  The additional spin imparted by the backspin barrel however tends to react with cross-winds in very unpredictable ways.

Finally, it should be noted that contrary to popular belief, shots from  backspin barrels do not lose velocity faster than those from normal barrels.  They do in fact maintain a slight velocity advantage over their normal counterparts due to the decrease in wind resistance related to the Magnus Effect.  Two factors related to this must be pointed out:  First, this is not a significant velocity advantage until near the very end of the ball's flight.  Second, once the velocity and backspin drop sufficiently to cause a failure of the Magnus Effect, the remaining speed is lost much faster than that of a ball fired from a normal barrel.***

I realize the above didn't directly answer your question, but they were factors that I felt needed to be considered before going on.  The information below is going to assume that the barrel is correctly installed and is being fired at optimum velocity* by an experienced user.**

First, an explanation of the way I refer to ranges, and the thinking behind it is in order:  Point blank range is anything within 10 feet--basically, it's close enough that you can expect a surrender if it is demanded.  Close range goes out to about 30 feet--it's farther than point blank, but a surrender is still a possibility given the right circumstances.  Medium range is 30 to 60 feet because 60 feet is about where a shooter has to start putting significant arc on the ball in order to reach targets when firing in the 280 to 300 fps velocity range.  Long range is 60 to 110 feet because 110 feet is approximately the point where shots fired at the aforementioned velocities have decreased to about half of the original speed.  (Which means impact energy has decreased by about 75%.)  Anything beyond this is extreme range.

At point blank and close ranges there is essentially no difference in barrel performance.  The differences you do get are related to the specific performance characteristics of each barrel.  The "dive" that the ball takes as it leaves the Apex tip means that shooting over cover with any depth may be challenging.  (Imagine firing over a car hood and having the ball smack down into the hood.)  Also, the few feet it takes a ball to stabilize after leaving a F/L barrel means that the shooter is not going to hit a specific small target (such as a pod) at point blank range, but will still not have to worry about missing a man-size target.  (Imagine the up and down motion of a Frisbee when it first leaves the hand.)

At medium ranges, the standard barrels have a slight advantage.  The balls launched from them still maintain a flat enough trajectory to easily engage most targets or small portions of targets while having more accuracy than a ball fired from a backspin barrel.  The balls fired from the backspin barrels on the other hand are starting to experience accuracy issues due to instability inherent to the backspin that gives them their extra range.  Hitting a man-size target is still guaranteed, but engaging a small target area protruding from cover is more challenging than with a normal barrel.

At long ranges, the question of which barrel is better is more dependent upon the playing terrain than any other factor.  For open terrain, I would prefer to have a standard barrel.  For heavily wooded terrain where the flat trajectory provides a definite advantage, the F/L or Apex is more advantageous to have.  The one advantage that the backspin barrels have at this range in either terrain is as you mentioned above, the angle at which the cone of fire intersects the target area.  This provides two distinct advantages.  First, it provides a larger target area, which somewhat offsets the accuracy issues at this range.  Secondly, the angle at which the balls hit the target means that more energy is imparted upon impact which increases the possibility of a break rather than a bounce.

At extreme ranges, the backspin barrels are definitely preferable to normal barrels.  Breaks are quite unlikely at these ranges, but the balls coming in at a horizontal trajectory have a better chance than those striking the target with glancing blows.  Furthermore, the backspin barrels extend the far end of the extreme ranges beyond what normal barrels can do at legal velocities.  While eliminations are very unlikely at these ranges, they are more likely with the F/L or Apex than with barrels that can't even put balls out there.  It is the characteristics of the backspin barrels at long and extreme ranges that make me consider them to be tools for suppressive fire rather than "sniper" markers.

I rambled a bit; I hope at least some of this addressed your question.

* A5 260-265 fps; 98 (old) 270-280 fps
** One who knows the importance of keeping the F/L clean and holds the marker correctly.
***This is why balls fired from a F/L seem to "flutter and die" at the end of their flight.




Edited by Mack - 28 May 2008 at 12:13pm

^^^ The F/L provides one-shot capability through most such firing lanes* out to medium range.  I would use at least three round bursts beyond that and wouldn't bother with trying those shots at all at extreme ranges.  (You could probably do the same with an Apex, but outside of having one long enough to determine I couldn't stand it, I don't have a lot of Apex experience.)

Where the F/L really excels is in wooded areas where the overhead cover is relatively low but the ground cover is sparse.  In these situations you can open up on helpless opponents and laugh as their return fire breaks on the overhead foliage 10-15 feet in front of them.

*Assuming they aren't insanely small.