How to save $7 in an hour and a half

by Doc Nickel

A week ago, I had the opportunity to get out on the field and play some ball, for the first time in about three years. I took with me a "parts box" 'Cocker I'd assembled for a similar last-minute game several years ago, and despite it's total lack of maintainance or even lube in those intervening years, it worked just fine.

Not, however, perfectly.

I'm still a big fan of 'Cockers because I'm a tinkerer. 'Cockers are Paintball's Harley Davidson. You're not supposed to use 'em straight off the showroom floor. They're meant to be modded. happy.gif

One of the few things I didn't like on this gun was the bolt. It was the only one I had that fit the 2K back block, it was lightweight Delrin and had a matching Delrin pull pin, so for the situation, it worked fine.

However, with the Tornado valve and large internal spaces, I should be able to run this badboy at 160 to 180 psi. If I can believe my gauges, I have to give it 220 to get it up to speed, and efficiency (as in shots per tank) is nothing to write home about.

I had a parts-box 'Cocker back in 1999 that'd get a theoretical 1600 per 3K/68, with a nearly identical Tornado and Max-Flow/gas-thru setup. And I say theoretical because I never really had a full 3K fill, since I always had to draw off of 3K SCUBA tanks or my HP compressor which never really gave more than about 2200 to 2500 psi.

The only problem with this bolt I have is that it's huge- the classic "let's make the opening as huge as possible for the most flow!" design that so many makers have used and still use. It's kind of counterintuitive, but a smaller bore bolt, in these kinds of setups, tends to be more efficient- yes, even over the Tornado's own matching Lightning bolt.

The idea is to keep the port size the same from the face of the valve to the face of the bolt- if the air burst is allowed to expand more than it needs to, energy is lost.

So, I got out a chunk of Delrin and started making a new bolt. Pretty standard job, but while I was making it, I started thinking about one of the other things I didn't like about the parts-box gun; the ball detent.

The detent was whatever I happened to have laying around at the time, and it works, but it's the older style steel ball type detent. I tend to prefer the kind with a delrin ball, but I don't have any on hand (that aren't already part of an assembled marker) and looking around, it seems they're getting hard to come by. Ebay only has a few, and they're all steel ball. Compulsive has some CP detents- which I don't like the look of- but most are sold out. I don't want to spend $25 plus shipping for a gimmick "magnetic" detent either. Some other dealers have detents in stock, but they're all steel-ball too.

So, I figured I'll make my own. happy.gif

I had a couple white Delrin balls left over from a previous project, plus I even had a scrap of stainless 7/16" hex stock from a customer's production-part order, so all I needed to do was put 'em together. happy.gif

Nothing to it, except for a bit of time and some care in measuring. Face one and and turn the hex stock round, then thread to 3/8"-24. I couldn't thread all the way to the shoulder, so I gave it a clearance cut at the base of the threads.

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Cut to length, chamfer, drill, then part off:

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A little careful filing to get rid of the burrs, clip a bit of spring from the junkbin, make a staking tool, stack 'em together and give it a whack with a hammer.

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And voila!

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Face the flat end, trim it up with a file to make it nice, sand 'er smooth and she's ready for her close-up:

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Tested thoroughly- okay, half a hopper- and it works great. Next time I roll out the buffer and do some polishing, I'll give 'er a high shine. happy.gif


Posted on Jul 2, 2012, 12:24 AM

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  1. Parts, you say?. OmniMech, Jul 2, 2012
  2. Can't wait to hear how it performs in the field.... Snowtroll, Jul 3, 2012
    1. Keeping in mind.... Doc Nickel, Jul 4, 2012


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