SpudFiles

I've recently (finally) finished my semi-auto QEV gun, (showcase in a few days), I already had a cloud. What comes next? 3 round burst of course! Yes I've been playing too much call of duty...

Anyway, there are a few kinds of burst. The kind where if you let go of the trigger "early" the burst finishes, or the kind where the burst stops. I'd prefer to have designs where it finishes, but either works...

I have a broken Red Ryder, so I plan on taking the barrel and stuff from it... so it'll fire bb's. I'd like to keep the cost of this down... I'm fine with working a lot on this, but I don't want to spend TOO too much. I'll also don't want it to be electric/computerized, but I guess it could be.

Anyway, I'll keep thinking about it, but I don't really have any great ideas for burst fire. I guess you could limit the time the air could flow, but that wouldn't be a very reliable 3 pellets. If I think of anything (actually good) then I'll make sure to post. Please help me think of something! I'm kind of surprised no-one has asked about this on here before (at least, I couldn't find anything.) I'd like this to be pretty high pressure btw.

Burst fire is pretty tricky without electronics, but it probably could be done with some ingenuity pnuematically.

If you're not completely tied to the 3-shot burst, which it seems you are for "realism," but a really simple way that I've done is to just take your semi-auto QEV platform and replace your single shot loading mechanism with a small cloud chamber and possibly a detent. That probably won't get you exactly three shots every trigger pull, but if you have an adjustable detent you could probably get pretty close and still get a nice "pop-pop-pop" from the high-pressure combined with a good detent. Of course the problem with detents is feeding, but I've found that the high flow from a QEV rarely misfires even with a near empty cloud chamber

I'm not really committed to 3 rounds/burst, but it would be nice to have a consistent burst, be it 4, 5, or whatever.

Currently I'm thinking of connecting the QEV output to a tee with parallel elbows on each side (looks like -E), the QEV connects to E and - connects to the barrel. I think this would be a very fast burst and I don't know how I would get them to not jam.

Another idea I had would be to have three pressure sources in a row connecting to one larger air chamber that leads into the barrel.. Inside there's a piston which seals the barrel. If you could trigger it or push it to start moving back, as each pressure source gets in front of the piston they would blow back the piston to the next hole. An advantage of that system is that it keeps firing even if you've let go of the trigger ( which could be used to set the piston in motion).

Also, I've got an idea but it's not really burst...
Anyway connect regulator output to two separate pressure chambers, and attach each of those chambers to a 3 way valve (one is connected to what was the pilot hole) and pilot the QEV with a pop off valve. One chamber charges while the other fires, so you get two rounds per burst. One when you pull the trigger and be when you release.

I had another idea that's basically the same way real burst works. You attach the trigger to gears, so the small motion can turn a cam 3 times which triggers a 3 way semi auto 3 times. The problem with this though is the bps of the burst depends on the speed of the trigger pull. Also, the trigger would be very heavy.

Also, I made a drawing for what the blowback burst might look like...