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[REDACTED]: Developing an all-new [REDACTED] Paintball Gun
Part 4: Building a Functional Mark II Prototype

Project X

At this point we just need to add a feed mechanism in order to be able to properly fire paint. This, of course,
is a straightforward task, as there have been spring-fed markers since the very early days of the sport. There
was only one minor issue, in that we were [REDACTED]. In a normal spring feed [REDACTED] the passage at the end.

This, however, is easily enough accomplished by [REDACTED]. Here I hand-turned
a [REDACTED], and [REDACTED].
(Keeping in mind this is just a prototype- that was just an expedient fix.)

Project X

I only had some 10-round springs on hand, the last of a handful I bought from Sam Tussing back in- if the
box is to be believed-1998. Again, this is just a prototype, so I made an extended plug long enough to
put the proper tension on the spring. The finished marker should eventually hold 15 rounds.

Project X

The plug slides in snugly and is attached with a single 6-32 screw.

Project X

Now, the earlier air plug worked in that I was able to connect a bulk tank and remote hose to the gun, but
naturally I wanted [REDACTED], so I needed a self-contained system. The particular layout
on this marker does not [REDACTED], so it will most likely be a dedicated 12-gram-only marker.

So for the sake of expedience, I took the big test plug, and turned it down into a new adapter to accept
a CCI Phantom quick-change "bucket". It was a bit tricky, as the changer uses a 14tpi 4-lead thread.
The 4-lead wasn't a problem, but the 14tpi was. In order to cut 14tpi, I have to set the lathe to 3.5tpi.
(3.5 x 4 = 14.) My main lathe could only go as low as 4 tpi.

But, just for the prototype, and because the threaded section was so short (about half an inch) I was able
to cut 16tpi 4-lead threads, and made them a little deeper- that is, looser- than normal. The 'bucket' then
threaded on just fine, and is still plenty safe and secure. (Again, just a prototype.) The part was finished
off by boring and tapping for a CCI piercing pin assembly, and cutting a hex on the end so that it
could be tightened into place with a wrench.

Project X

And there we go. It's actually not bad, from both an appearance and use standpoint. Doesn't get in the way
of using the [REDACTED], and yet it's easy to access for fast changes. Any production version
of this marker will probably have a [REDACTED]. But for the time being, this is actually a nice, workable solution.

Project X

I also wasn't particularly happy with the trigger, which wasn't retained well. I'm already drawing up an
improved version for the MkIII, but for now, I decided to add a guide pin in order to stabilize it.

Project X

And, as of the 21st, some 22 days from starting with an empty workbench, I aired it up with the 12-grams
for the first time, and shot the first tubeful of paint through it. It worked like a champ, feeding and firing
perfectly even when [REDACTED]. Accuracy and sound levels were about what you'd expect from a [REDACTED].

Project X

I even had my third-ever indoor accidental discharge with it. :)
The[REDACTED] needs a little refining, in that my quick-and-dirty '[REDACTED]' was a touch too long,
allowing the [REDACTED] enough to jam the bolt open. That happened on the second magazine,
and so I brought it back inside, removed the feed plug, spring and follower, [REDACTED], aimed at the far
wall and pulled the trigger. The ball hit this box I had sitting on the table of one of the mills and splattered all
over the place. You can see a splot on the whiteboard in the background too. :)

The ultimate cause was the fact the gun does not yet have a ball detent. That's coming next, but at the time
I was too excited to try it to wait. The last ball rolled into the chamber, letting the [REDACTED]
enough to stop the bolt. That ball stayed in the barrel even after I removed the feed parts. :)

Next up, the finishing touches....

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