Here you can see the additional piece added to the back of the turret to achieve a seal on the stock o-ring.
Here it is close up, to get the idea.
To start we'll hack off the plunger tube up to within about 1/8" of the wider area. We'll also chop down the front close to the pivot. If you hold the turret up to a lamp it will be easy to mark for that cut.
Next, a few cuts to free up the area where we'll be placing our barrels.
Next let's dremel out what's left of the turret close to it's final shape. This is a good time to cut our barrels as we will be checking the fit soon. It's a good idea to square up the ends of the barrels now to insure a good fit as well.
Now let's do a test fit. I found that the corners needed some extra attention. Here's the before:
Here is the fit after some trimming with a utility knife and some filing:
And here is what's left of the turret after finish filing and cleaning.
Now we'll start on the back. Here's what it looks like after a rough cut:
These are the cuts I made for a CPVC stub. There are of course many ways to hook your turret up to a blaster. This is what works for me in this application. The length of CPVC used will depend on your application. I try to keep this to a minimum to reduce deadspace. Clean up the edges and flatten the front of the plunger tube before the next step. If you want to try enlarging the air holes now is the time to do it.
Be sure to clean and dry everything, especially the o-ring. Spin the turret and jam a soapy artists paintbrush through the air holes to clean the o-ring from the inside. Now let's glue up our barrels and stub. I used super glue which fits my working style. Epoxy is great too. If need be you can compensate for any off angle barrels now. The front of the stock turret can be used as a barrel spacer if you like. They are quite solid without one though.
Now we can fit the piece of plunger tube to the back of the turret. Cut a slice of plunger tube to about 5/16". Try to jam that slice of plunger tube between the back of the turret and that ridge that's left from the first cut. The pic shows this better than I can explain. Trim it down slowly till it fits quite tightly. If it is cocking the turret to one side on the pivot try moving it around a bit to move the points of pressure. Now check the seal and alignment of the turret. If it's too hard to advance the turret trim a bit more. Glue it in place being carefull not to get any glue going where it shouldn't. Trim it down to a sort of half moon shape, bevel the edges as you see fit.
Here is a look at the front of the stock turret and the space for a barrel spacer on the modified one.
And this is the finished product(s). Note that I tried a slightly taller plunger tube slice on the SSPB's turret to try to increase the efficiency of the seal. It did make a noticeable difference but is slightly harder to turn.
Note that I used a fairly short piece of CPVC glued to the face of the plunger tube to connect with my blasters. It is tight and stays put but doesn't go quite all the way to the back of the coupler. I don't think there's a tremendous amount of strength in the pivot point of the Tek-3's mechanism so I don't want to jam this in there too tight. I haven't tried enlarging any of the air holes yet. There does seem to be room there. Ranges? Very good. I tested stefans and stock darts and the ranges were within 10-20% (of the ranges for an equivalent sized barrel) for the smaller turret and 10-15% with the larger. The trick with the 1.6" barrel length for me, to get stock darts to fly best, was to twist them in only about 1' and then prime sharply to vacuum load well. Durability? Dunno, haven't broken them yet.
Edited by iamthatcat, 03 January 2012 - 10:51 PM.