Airsoft M72 LAW rocket launcher

Step 9 Install Airsoft 40mm grenade shell

I chose the Mad Bull XM PB4 40mm grenade shell for three big reasons.

1. It has the fill valve in the back.
2. It has a large gas reservoir.
3. It is loud.
4. Is has the fill valve in the BACK.
5. Mad Bull has the reputation of being dependable.
6. IT HAS THE FILL VALVE IN THE BACK.

http://www.madbullairsoft.com/English/index.php?main_page=product_info&cPath=1&products_id=14

These are normally used in M203 grenade launchers.

Orient the fill valve towards the bottom for easy filling.

Comments

[yish1919]

where did you get the gas can or online? cuz i buy things online more then in the stores

[MrTinkerer]

local store. i dont like paying for shipping.

[airsoftchase]

will the s-thunder fit as well as the mad bull in the coupler?

[MrTinkerer]

most likely yes. Remember the s thunder and the mad bull is a replica of a 40mm grenade shell. With that said, they will mostl likely have the same diameter.

[tj1221]

That grenade is $80... rather expensive... is there anywhere to get it cheaper, or a different brand of grenade that is similar?

[MrTinkerer]

Yes, it is one of the most expensive 40mm grenade out there. But it is the best for this application.

If you really want to go extra cheap, look into building pnuematic spud gun. The keywords to look for is "sprinkler valve", "solenoid", "orbit", 'rain bird". You could probably build one for about 50 bucks. Oh, buy a really good bike pump.

That is actually my new project. A Nerf launcher based off a spud gun (non-combustion), but a lot more complicated. Lots and lots and lots more complicated. 

Don't worry, I plan to make an instructable for it. Y'all just have to wait till late summer 2010. 

[mazingbrainiac]

i bought the right grenade, but it is too small for the coupler, and im fairly certain i bought the right one of those too. did u put anything inside the coupler or around the grenade b4 inserting it?

[MrTinkerer]

No I did not put anything inside the coupler other than the grenade and the pvc pipe. What is the Pt. No. number on the label of the coupler?

[mazingbrainiac]

i ordered the 3000-215, http://www.buyplumbing.net/index.html?pg=pd&_i=3000215, but the label of the coupler that came just said cp 215, 2" CI, PL, ST to 1 1/2" PL, ST. apparently form this company http://www.missionrubber.com/index.html

[mazingbrainiac]

...yea, the 3001-215 is 2 to 1 1/4 which is the right size, and the 3000-215, is 2 to 1 1/2 , u should change the item in the materials list, it confused me

[MrTinkerer]

I put the part number in the parts list (Step 1) and said the same thing again in Step 5. I even took a VERY CLEAR picture of the coupler and put a notation around the PART NUMBER. Part number 3001-215 is visible in at least three (3) places on this instructable. I'm not really sure what part of that is confusing. PROFLEX Part number 3001-215.

[tinovw]

sooo clean. Very nice.

[Bigsexy1]

would you recommend using c02 because I was told it breaks the grenade. have you shot it powered by c02?

[MrTinkerer]

CO2 is no good. the XMPB4 is CO2 capable BUT the co2 needs to be regulated down to less than 400psi. To regulate co2, it needs to be purely gas, not liquid. To get good performance you need to load LIQUID into the grenade that converts to gas when the valve opens. Only thing that can do that safely is Green Gas.

[MrTinkerer]

to add to this further, yes we did try CO2. We tried 3 times at 120psi, 250psi, and finally at the max 400psi. Very loud bang, BUT the nerf did not even leave the tube.

[geoffpeplau]

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