Let's take a look at each requirement and see why they're so important.

1.The plug MUST be difficult to insert and remove.

It has to be in tight to do its job. When a paintball is fired, the plug MUST stay in the barrel. The plug is working against air pressure (which builds up between the moving ball and the plug), expanding CO2 (behind the moving ball) and the inevitable impact of the ball itself. If the plug can be shot out of the barrel, it's not doing its job. A flying barrel plug can put out an eye as quick as a paintball can. The rule of thumb for barrel plug tightness is simple: If you don't "grunt" every time you insert or remove your barrel plug, it's not tight enough!

2.The plug MUST be clean and dry.

Dirt, paint, shell fragments, even water, on the "O"- rings or in the barrel of the marker will act like "lubricants". These "lubricants" will reduce friction between the rings and the inside of the barrel. Reduced friction equals flying plugs. Also, if your barrel interior is hard-chromed or teflon-coated, the plug has to be that much tighter. Anything that makes the paintball travel more smoothly will affect the performance of a barrel plug.

3.The marker MUST have a muzzle velocity set BELOW 300 feet per second (fps).

A hot marker will blow the plug out of a marker that much easier. Besides, what are you doing with a marker shooting over 300 fps, in the first place?

4.The hole in the plug MUST be clear and free of obstructions.

The hole is there for a reason. It is to allow the air, that's stacking up in front of the moving paintball, to escape. Without this hole, the plug would be shot out of the marker every time.

5.The "O"-rings MUST be in good condition.

The job of the "O"-rings is to hold the plug in the barrel. If they are torn or cut, they won't do their job. If they have flat surfaces (from prolonged use) they won't fit in the barrel as tight as they should, and they're not doing their job. If any are missing . . . well, they aren't there to do their job at all, are they?

6.The plug MUST be inserted as far as it will physically go.

Not as far as your whimpy friends can push them in, but as far as they are MEANT to go. Most plugs have an oversized end which is supposed to be in contact with the face of the muzzle, when properly installed.


Before you insert your barrel plug, put your small (or pinky) finger in the barrel and to see if it is clean. If it's not clean, you should run a squeegee through it. If it is clean, jam that plug in. DON'T LOOK DOWN YOUR MARKER'S BARREL -- FOR ANY REASON!


I always like to "plug and empty chamber". That means there is no ball in the barrel, ready to fire.


Just fire the ball you have in the marker and don't cock it, afterwards. Apply the safety (if you have one). Put your plug in.


Tip the marker so that no balls are feeding. While keeping it tipped, fire a few shots (to ensure the barrel is empty). Still keeping it tipped, grab the cocking handle, pull the trigger and allow the bolt to move forward (slowly). Once the bolt is in it's forward position, apply the safety (if you have one). Put your plug in.


You want to accomplish the same thing as the above. It really depends on how your semi action works.


As an added precaution, you can turn the plug in your powerfeed to prevent balls from feeding into the marker.

If you follow the above procedures, you will notice that they eliminate the chances of the marker firing accidentally. Before we go on, an important note about blow-back semis. If they are dropped (barrel facing up) or are banged from a force from the rear, the bolt can come back far enough to load another ball and fire. Handle your marker accordingly.

Basically what you are trying to do is to negate the fact that the marker is cocked, loaded and ready to fire, when you put the barrel plug in.


You should change the `O'-rings on the plug every year, or when they start visibly flattening out. Rinse the plug in hot water, when you are cleaning your gear. Do not oil the plug.


Go out to the range, remove the plug and chrono in at a safe velocity. Insert the plug and point your marker "down range". Fire off one shot. If your plug flies out or is even partially pushed out, it's not tight enough. Check the pressure relief hole, the "O"- rings, and how the plug fits in your barrel. If everything seems okay, you are going to need a plug that fits tighter. If the plug stays in -- clean your barrel; you just broke a paintball in it!


Just as a healthy reminder: NEVER fire your marker in camp, regardless of the type of safety device(s) you have on your marker.

DO NOT rely on ANY device! The ONLY device that makes a marker safe is YOU!