10 replies to this topic

[Jeo]

Howdy all!

First up I want to give credit to bakabill on OzNerf for his semi auto Magstrike that provided the original inspiration to have a go at this (and in a round about way, I should probably mention Banshee's Blast-Strike and Lefty's Mega-Strike too).

Basically my situation was that I'd seen Bakabill's Magstrike write up here and thought it was worth a crack, then realised I had a only somewhat reliable Rapidfire AS-20 sitting at the bottom of my Nerf cupboard. Thought about it for a day or two and decided bugger it, I'll just pick up another BuzzBee Ultimate Missile Blast (BBUMB) and give this a go.

I'm not going to go into any real detail with this as it should be fairly self explanatory, but I am happy to answer any questions. Full post now on Foam Dart Goodness.


Where it's at currently...


The tube from the fill valve at the bottom leads to the stock BBUMB check valve.


The AS20 trigger is attached to stock lever from the BBUMB.


It's then sprung to pull the trigger back and to close the tank.


I took the whole post that originally held the lever in the BBUMB too. Made things much easier.


Trigger in it's natural position.


Trigger pulled.


The trigger has been removed in this photo so you can see the slot I had to cut in the bladder tank.


This random orange thing was glued in the bottom of the shell as a stopper for the bladder.


See! Here it is with the bladder fully expanded, hard up against the stopper.


I had to do this so that it didn't interfere with the trigger mechanism.


That's about it in a nutshell. The barrel is 300mm of 17/32 brass, the back half of the RSBC holds 4 darts, there's a screw on end cap on the end.


So how does it all work? From the top;

Unscrew the end cap, insert 4 darts, screw it back on.
Pump 10-15 times.
Press the fill button at the bottom (fills the BBUMB tank from the AS20 bladder).
Flick the front of the blaster towards the ground (gets another dart jammed in the barrel).
Pump 10-15 times.
Pull the trigger to fire (opens the BBUMB tank).
Press the fill button, flick the front of the blaster towards the ground, pull the trigger to fire.
Press the fill button, flick the front of the blaster towards the ground, pull the trigger to fire.
Press the fill button, flick the front of the blaster towards the ground, pull the trigger to fire.

Tada! Start at step 6 and you can fire 4 darts in 3 seconds, each hitting ~30m flat. Check the video below for an example (albeit nice and slow so you can see what's going on).

FB Video - Canberra and Southern NSW Dart Tag
(I tried so many times to get that to embed, nuts to that you're getting stuck with a link)
PS: 'Like' the page while you're there!

Edited by Jeo, 08 May 2012 - 10:17 PM.

[shmmee]

Fun idea. My only gripe - and its one that's easily fixed - is that your bladder overfill valve is disabled by the orange piece you glued in. Over pump and you'll have a 'sploded bladder.

[hamoidar]

Very nice! This things is pretty cool! I agree with shmmee, you should glue a piece of plastic across the bladder tank end, so that the over-pump-valve will still function. I would also recommend not painting the barrel black. If you were to carry this under your arm, someone may mistake it for a real firearm. Overall, nice job!

[Acerised]

WOW! Great idea!

The only thing I can suggest is using a hopper clip to avoid the flicking and so, faster rate of fire. That's if your after rate of fire.

Regardless great job!

[Jilliop]

I agree with the hopper idea. Also, can you take a moment to explain how you attached the refill button to the BBUMB check valve? Did you just use a tube and then surround it in hot glue or something?

[Jeo]

Cheers guys.

How does the over pressure vavle in these normally work/where is it?

To attacht the refill button to the BBUMB check valve was simply a case of running some of the left over tube that used to go to the Rapidfire plunger into the back of the check valve. I think I used a chunk of foam matting to fill the dead space, 2 party epoxy to glue the tub in place then sealed with hot glue.

[Blue]

'Jeo', on 09 May 2012 - 03:36 AM, said:

Cheers guys.

How does the over pressure vavle in these normally work/where is it?

To attacht the refill button to the BBUMB check valve was simply a case of running some of the left over tube that used to go to the Rapidfire plunger into the back of the check valve. I think I used a chunk of foam matting to fill the dead space, 2 party epoxy to glue the tub in place then sealed with hot glue.

Pump up the blaster and push that button on the bottom of the bladder and it will release the air. Stock, it presses up against the back of the shell; if you put a metal plate or something so the button presses against it that should work.

[Jeo]

Ohh, I think I get it, cool. So the front of the bladder would originally force the top of the trigger down slightly, causing it to vent?

[hamoidar]

'Jeo', on 10 May 2012 - 08:34 AM, said:

Ohh, I think I get it, cool. So the front of the bladder would originally force the top of the trigger down slightly, causing it to vent?

The air release valve is actually on the cap of the bladder itself. If you look, you will see a button-like thing sticking out of the bladder cap. When the bladder expandes to it's max, the button presses against the shell wall, releasing a bit of air.

[Banshee]

If I had a nickel for every time I've seen a revision of my original Magstrike mod pop up somewhere on another forum, I could build 5 more semi-auto Magstrikes. Haha. You're the first to do it in a RF20 though, so props for that. It makes me proud to see that someone actually likes the things I do, so keep them coming! I'm still trying to find a way to make it true semi-auto. Not that it would fire any faster anyways. In the time it takes you to drop another round in the RSCB into the barrel, you can easily hit the fill button, so it really doesn't matter. Unless you're using a hopper... which I don't.

[Jeo]

Ahh, I understand. Thanks Hamoidar.


My pleasure Banshee. Always good to see interesting mods like yours and see if people can create their own take on them.