This is a post-mod writeup, so I don't have any in-progress pictures.
Mods to do:
- Rear loading
- Modular barrels
- Improved plunger to turret seal; improved plunger to turret airflow
- Increased draw
- Catch upgrades
- Adapter for removable stock
Drill out the back of your turret to allow for real-loading. Sanding drum on a dremel works too.
Unscrew the screw, and then glue all the ratcheting pieces together, as well as the entire rotation nub together. This is so the turret does not slip when rotating under the increased friction from the seal mods we will do later.
I used 6" of 5/8" ID x 3/4" OD polyester tube for my main barrels. This is for 3 reasons: 1) Shooting megas 2) Allowing 1/2x5/8 polyester tube (or CPVC too) to nest inside all the way to the back for single micro barrels 3) Allowing micro barrels to nest inside with some gap for inlines.
I harvested the stock shotgun encapsulation on the turret to use as a spacer for my mega barrels. Center a 3/4" spade bit on the natural dimples in the 3-shot intersections for perfectly spaced holes.
I glued my barrels in by solvent-welding the base plate and the barrels, and then throwing the spacer on while the weld formed.
Simply push the 1/2" ID x 5/8" OD polyester tube all the way back for regular single barrels.
I cut off the stock piece entirely and replaced it with 5/8" brass nested in the 5/8" ID polyester. Finished by superglueing a rubber washer to form the seal. This improves the seal and gives you much better airflow.
After cutting off the stock connection, bore it out to fit 5/8" brass. The polyester tube is only there for support of both the brass and the rubber washer.
The brass runs into the plunger tube. The polyester is solvent-welded to the outside. Be sure that your brass doesn't go into the usable volume of the plunger tube and thus impede your plunger rod movement.
I started with a 1/2" connection piece and slowly dremeled it down until when put into the shell, there was slightly less than 1/8" distance between the piece and the back of the turret. Ideally, you want it to be just long enough for good friction between the rubber washer and the back of the turret, but not so long that this greatly inhibits turret rotation.
As seen in the previous pictures, you will have to make judicious cuts on the rubber to fit it, such as a dimple to fit over the rotation mech. Also, make sure that the hole in the rubber is 5/8", else you did those airflow mods for nothing.
Cut the front set of gasket off of your plunger head. It serves no purpose except in limiting plunger travel. You can also fill in the space with hot glue, though I found that when done improperly, this actually decreases range as friction between the plunger head and the plunger tube is too high.
Your plunger rod will now be able to travel forward more. You also cut down on dead space and achieve more efficient pressurization.
Accommodating the increased forward travel
Glue your catch in the down position
This is obviously easier if you take out the spring in the back
The original purpose of this mechanism was so that you can't pull the trigger without the priming bar in the forward position. This is stupid for two reasons: 1) it actually inhibits plunger rod travel forward and 2) now you can "fire" the gun in the back position to "undo" priming the gun without dry firing.
Cut off the ^ shape on the catch:
This is the main reason why you had to do the previous two steps. The ^ impedes our increased forward stroke, but is also vital in stock operation to push the catch down so the trigger can operate it.
Edited by Zorn's Lemma, 20 June 2011 - 10:07 PM.