Controlling ROF in a BB SMG without a hammer/bolt

Building or modifying BB, Airsoft, and Pellet type of guns. Show off your custom designs, find tips and other discussion. Target practice only!
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Hurricane Air Arms
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Wed Oct 25, 2017 11:13 pm

Firstly. A quick hello from Aussie Land once again. And regarding the "suckering in a new generation post". I think SpudFiles is doing great considering we broke the all-time user record online last year. So we're all still very much relevant. Moving on...

So this is one of the big things that plague home made air gunners in the SMG/Carbine/Auto department. Controlling your ROF in your 1000-round bullet house. Etc. Etc.

Over the last 12 months I've gained a great deal of mechanical knowledge and it seems that where there is a problem, there is actually a genuine solution. When I first got into airguns about 10 years ago, I wondered how on earth Semi Automatic air guns were made. It was like only the Einsteins and Browning's had this magical knowledge of one shot one pull. Over time I realised you could actually build a semi auto with good power in a matter of hours/days.

What I mean is, controlling the ROF on a fast firing BBMG was never thought possible by myself, but I've since had lots of success with little interrupters and backspinners and realised just how magnificent compression springs are. Seriously. Where would we be without the modern compression spring?

Anyway, this is my newest concept for ROF control and I hope it communicates to everyone from highly skilled to the borderline noobs!

:wink:

[img]flo.png[/img]
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Zeus
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Thu Oct 26, 2017 3:14 am

I'm quite sure you might find some similar concepts in this here thread

http://www.spudfiles.com/hybrid-cannons/topic19504.html
/sarcasm, /hyperbole
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jackssmirkingrevenge
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Thu Oct 26, 2017 5:37 am

hectmarr wrote:You have to make many weapons, because this field is long and short life
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Hurricane Air Arms
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Fri Oct 27, 2017 1:35 am

Yeah I’ve seen all of those. Except this uses magazine spring power to hold the BB in place. there is no “chambering” process, the round is chambered automatically when follower in the mag is engaged. Hence why I posted it.

Lots of people will be wondering about the hardest part of this design. It’s probably the millimetre precision needed in order for a successful automatic chambering. A mill too far forward and you get no firing pressure, too far back and the round may not even chamber!

Also. The links you guys provided are of a) A hybrid that doesn’t seem to resemble what I’m talking about, and some cloud BB’s mg’s pressurising a firing chamber full of BB’s. One of the hopups is even located in the wrong location...

This design doesn’t use cloud. It revolves around an entirely unpressurised magazine. So you can maintaina consistent feedand good power. With this sort of design the cloud feed really becomes redundent. Granted you have the skills and technical know-how.
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Zeus
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Fri Oct 27, 2017 3:47 am

So, I'm curious on specific details, your concept seems to work, but you haven't got many details of your actual builds. I have 4.5kpsi available, a lathe (with vertical slide), TIG and MIG, all the hand tools and enough skill to royally screw up the first 17 prototypes.

As I understand, the detent/hopup doodad first pushes the projectile rearwards into a seal, as pressure is increased, the projectile moves forwards and escapes. A few of the problems I can see, what stops the projectile being pushed slightly forward and allowing air to scoot around it? Secondly, how strong it the magazine? It'd need to be remarkably strong, otherwise the projectile again is pushed down and air escapes. I'm not knocking your idea, not in the least, we need innovation here! There are just a few problems I see and I'm curious as to how you've addressed them
/sarcasm, /hyperbole
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Hurricane Air Arms
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Fri Oct 27, 2017 9:55 am

You’re dead right. about air around the BB.

The only way to truly fix this would be to completely remove ant slow build of pressure and make it an immediate firing. That way all the seal and ramp are doing is holding the BB there briefly until it is popped by instantaneous pressure from the rear.

As for the meagazine. It won’t have to be strong, strength is not the goal, just a basica seal. The seal will fire one round with a more precise amount of pressure, and the next round as soon as it is seated in place.

I had the same question. trust me.

(Edit) OR just spring-load the seals at the rear, that way the Bb will compress them and require a pressure overide to decompress them. Once pressure overides the seal, the round should burst free. (Hopefully).
The Lord said "Whom shall I send, and who will go for us?"

And I said

"Here am I...

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