Chronograph for paintball in most cases is a device that works on the bases of radar. This radar measures the speed of paintballs in feet per second (fps.)
Since my last scenerio event I've been meaning to type something up on this. I never realized so many people make mistakes when chronying.
Two things to know:
1. Never accept +300 fps as good enough. The masks are rated for paintballs that are travelling 300 fps or less.
2. You need to fire two ball to get a true rating.
I. Now rule number one is simple. Safety first. If you think that doesn't matter than consider that the ball was never designed for the excessive pressure and may either break in the barrel or curve widely and inconsistantly.
II. You need to fire two ball to get a true rating.
Let's touch on this and use plenty of examples why I say this.
A. Highend electro pneaumatic markers.
i. Most regulators will hold a charge. When you fire once and adjust your reg you don't change the charge already in the reg. So your next shot will be similar to your first shot. If you shoot twice after an adjustment the second shot will show more true to your new velocity settings.
Note that even low end markers with regulators may hold charges and are subject to this.
ii. New regulators will be inconstant. You'll get a larger fluxuation in fps between shots. You need to know the average you're shooting.
iii. FSD (first shot drop) - this means your shot is less in fps than the following shots.
iv. ABS (anti bolt stick) - this is programming by the board to give more kick to the first shot to counteract FSD. The next shot will usually be a lesser velocity and read true. We don't want your first shot over 300 fps.
B. Lowend markers.
i. In this case we have CO2 spiking. The CO2 we have in our tanks is liquid and it expands to a gaseous state. If you put a freshly chilled CO2 tank on your marker or move a tank from cold to warm area the CO2 shall expand excessively in your marker. The first shot in this case will read high. The next shot shall read closer to your true velocity.
ii. Poppet style rear spring adjustments. ie Spyders, clones, cockers.
These rely on spring tension to move the hammer forward. Although you lessen pressure on the spring that spring is still bunched up and will change when expanded then compressed to the new positon. Your second shot with the spring resituated will show more true.
C. Paint and bore match.
No two paintballs are the same. Even in the same bag some balls may be .689 in diameter and some may be .687. The small balls will allow more air to bypass it in the barrel and not reach the same speed as a well matched paintball (tightly fitting paintball.)
Setting up for the FPS.
If I have to set to 280 fps I don't turn down my marker in small increments. I always prefer to turn my marker way down and work my way up. I'll turn myself down to about 265 or 270 fps and make a couple of small adjustments. I think it's better to fine tune knowing that you are within limits than trying to fine tune knowing that you are in violation.
Every Chrony I have seen has been designed to be placed within the last 2" of the barrel before recording the shot. Many people place the chrony wherever on the barrel. They were not designed for this.
With any hand held chrony never hold your hand across the back. This is where the radar sensors are. Always hold it by the top or bottom.
Sometimes you can blame the equipment. Some chronies won't read shots below 200 fps. Often times a weak battery in a chrony will give crazy readings.
You know what allan key or equipment you require to chrony your equipment. Make sure you have the necessary gear with you when entering the Chrony area. Nobody wants you holding up the line waiting for you to borrow allan keys.
Finally when your are done. Give another two shots at the chrony to make sure no mistakes were made.
This post has been edited by slinkyaroo: 17 October 2008 - 12:15 PM