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BFB Idea

Posted: Sun Jun 14, 2009 12:13 am
by MountainousDew
This is my Blow Forward Bolt/Breech idea, since I'm only 13 I don't have access to a lot of equipment... So I tried to design this with that in mind...
Image

It's basically a coaxial piston gun with a bolt attached to it that pushes the ammo forward to avoid double feeds. I left out the spring detent of the animation to keep it simple for me to make...

Questions, Suggestions, Flames?

Posted: Sun Jun 14, 2009 12:31 am
by inonickname
If I'm thinking of what you want to do then flow will be useless and deadspace will be massive.

Why not a toolies valve for this?

Posted: Sun Jun 14, 2009 7:10 am
by mark.f
Well, when the bolt moves back after the piston opens, you have the potential for a double feed, so what does this solve?

Posted: Sun Jun 14, 2009 12:11 pm
by dudeman508
mark.f wrote:Well, when the bolt moves back after the piston opens, you have the potential for a double feed, so what does this solve?

Not if he used really high pressure and small volume of air. Because all the air would of escaped before the piston would have time to fully return.

Posted: Sun Jun 14, 2009 12:26 pm
by Gaderelguitarist
I would try this in a tee piston valve because then you could reduce dead space to a bare minimum, because with this your chamber size determines bolt length.


Other than that it has potential.

Posted: Sun Jun 14, 2009 1:04 pm
by MountainousDew
Gaderelguitarist wrote:I would try this in a tee piston valve because then you could reduce dead space to a bare minimum, because with this your chamber size determines bolt length.


Other than that it has potential.
Is this what you're talking about?
Image

@Mark.f: And with the double feed situation, I added a spring detent in the diagram.

@Inonickname: How would you suggest I build this?


P.S. I had a dream last night,, where Chuck Norris kept saying quotes, like "Slow and steady wins the race." & "The best things in life are sometimes the hardest." & "Take the long road and you will be rewarded."... So I guess, I 'm telling myself that I should just try to build a blow-forward breech like clide did.

And with that said, Do you think I could use a blow-forward breech with a QEV+Pop-off combo?

Posted: Mon Jun 15, 2009 12:15 pm
by Gaderelguitarist
Yes exactly like that!

Though you still need to have the bolt seal off the mag, otherwise it'll shoot your ammo out the top.

Posted: Mon Jun 15, 2009 12:17 pm
by MountainousDew
Gaderelguitarist wrote:Yes exactly like that!

Though you still need to have the bolt seal off the mag, otherwise it'll shoot your ammo out the top.
I'll seal mag, I just didn't draw it...

What do think about the QEV+Pop-off combo idea?

Posted: Mon Jun 15, 2009 1:44 pm
by i-will
imagine having to reload the thing. there is no need to create deadspace in a mag.
http://www.spudfiles.com/forums/auto-qe ... 16399.html
this is a post i created a while back when i wanted to make a handheld (kinda like a m1911 or mac11). i'm pretty sure you'll appreciate it. it may have a bit of dead space but way less than a whole mag. let me know what u think or how you would improve it.

and yes a pop-off would make it 73 times more awesome.

Posted: Mon Jun 15, 2009 6:10 pm
by Gaderelguitarist
Only go for a QEV + Pop off if your bolt is very efficient.

Personally, I favor semi auto ideas because I feel they are more precise. Rather than wasting a bunch of ammo, they fire how ever many shots you need to make your point.

Posted: Mon Jun 15, 2009 7:28 pm
by MountainousDew
Gaderelguitarist wrote:Personally, I favor semi auto ideas because I feel they are more precise. Rather than wasting a bunch of ammo, they fire how ever many shots you need to make your point.
Exactly, that's why I'm not a fan of BBMGs. Sure they're fun, but there is (almost) no control over how many you fire.

Posted: Mon Jun 15, 2009 7:48 pm
by THUNDERLORD
i-will wrote:... or mac11)....
That's about exactly what I'd shoot for personnaly in a BBMG with a vortex, cloud or other bulk waste system,(anywhere from 1bb to barrel full o' bb's designs).
Something mac-11 or mac-10 similar with maybe a .375 bore. :twisted:

First I was thinking of mounting one on the dash of a nice car, in plain view (so it's not concealed,also not a "firearm"), in a holder like a metal ring.
The pressure tank could be inside the trunk and use a compressor also maybe.
I don't want one myself, too much road rage and it would be too much fun to use. :twisted: :P
...Personally, I favor semi auto ideas because I feel they are more precise. Rather than wasting a bunch of ammo, they fire how ever many shots...
My friend told me he doesn't want full auto anything, because say someone breaks in his house to steal the TV, he doesn't want to ALSO fire off full auto and blow holes in everything else and shoot up the whole place over just a TV!!! :lol:

@MountainousDew, Your design in the original post (top) looks very interetsing,
But it also seems WAAAAY out of scale.
To block the magazine it just needs a more solid longer bolt.
Also, the chamber volume should be much more to the front, otherwise, how will it pilot? 8)

EDIT: forgot, with the bolt blocking the mag, it seems the pressure will have no way out the barrel, Unless a seperate pipe vents the chamber behind the projectile. Seems like you're onto something though. :) :wink:

Posted: Mon Jun 15, 2009 10:31 pm
by Gaderelguitarist
with the bolt blocking the mag, it seems the pressure will have no way out the barrel, Unless a seperate pipe vents the chamber behind the projectile. Seems like you're onto something though.

Problem solved. And all you need is a drill.

Posted: Mon Jun 15, 2009 11:01 pm
by Technician1002
Gaderelguitarist wrote:
with the bolt blocking the mag, it seems the pressure will have no way out the barrel, Unless a seperate pipe vents the chamber behind the projectile. Seems like you're onto something though.

Problem solved. And all you need is a drill.
I like it a lot. Instead of 6 holes a center pipe for a single large port for better flow could be used. I'll have to bookmark that one. The hole in the piston and push bolt, changed to pipe can be the same diameter as the barrel with a simple bolt crossing the end to keep the projectile out of the piston push bolt assy. Kudos .. I like it a lot.

Posted: Tue Jun 16, 2009 12:02 am
by Gaderelguitarist
Thanks Tech!

Not sure I understand what you mean. Are you saying the bolt itself would be a pipe connected to the piston with a few holes cut in the sides? Wouldn't having a bolt the same diameter as the barrel require some modification of the Tee?

MountainousDew said he doesn't have much access to machines. I was just going for a simple to construct design.