S-Thunder 40mm M203 Grenade

[bean]

S-Thunder M203 Grenade

I have dabbled in M203's and the various methods they propel stuff at you for well over 10 years. I started playing around with a Toytec M203 which was basically a machine gun in M203 form. I then moved onto the Tokyo Marui style launchers using the shell. These were a great way to have a version of their shotgun mounted to your gun. It gave you good range but only fired 3 bb's at a time. It was cool but was still lacking that little something a M203 needs. I then tried some of the propane powered M203 shells ranging from Madbulls to Vanaras. They were cool but still didn't have enough power. I had a Madbull M203 grenade that ran of CO2 and fired paintballs and other such things. It was cool but the seals ate themselves very early on.

While attending SHOT Show this year I ran into a company I had never heard of before. They had a selection of mines (reviews on these later), an M203 shell that could fire paintballs or anything smaller, and a shell ejecting AR paintball gun. While talking with the rep he told me that there M203 shell was capable of running on CO2. Not only was it capable of running on CO2 it was designed for prolonged use of CO2 at high pressures.

Pros
-Cheaper than other alternatives
-Capable of running on CO2 with a small and cheap replacement core
-Robust I have fired the system more than three dozen times on CO2 and a bunch more on propane with no ill effect.
-Great sound when fired
-Really easy to reset the primer

Cons
-In order to use reliably on CO2 you require a different core
-Not colored like typical 40mm military shells (however this is also a pro more on this later)

Features

The S-Thunder M203 shell on the outside seems like a fairly standard shell for airsoft. However under its colored skin is a surprise waiting to be unleashed on its unsuspecting foe. Not only is this shell able to be used for airsoft but can be used by the scenario paintball player. This is done by having a hole capable of storing 4 standard sized paintballs in it. Now you may be asking how would the airsoft bbs stay in there won't they just flop out the end of the round? S-Thunder thought of this and have included a rubber end cap that fly's out like a slug with the pellets behind. You can purchase a bag of these slugs for $15.59 US and the bag includes 100 slugs. This saves you from looking around the field for a small red plug. If your cheap or don't like the idea of a rubber slug you can just wad kleenex in the end or put a piece of tape over the opening.

The standard core will last for a short while being used with CO2 but the seals will eventually go. Thankfully you can purchase a replacement CO2 core for $8.99 US. Personally I would have preferred this to be a feature in the grenade right from the start but at that price combined with the $39.99 US for the shell your still saving money compared to the $89.99 Madbull version. The replacement core is very simple to pop in. It comes with a nice thick grease to put into the 4 holes for the bearings. Once the bearing holes are greased up they just pop in and stay in place. Toss the spring in and put the primer on. Unscrew the shell of the M203 round and remove the assembly that was previously there and pop the new one in. This whole process lasted less than 5 minutes and can be done by just about anyone. This new core can be cycled for roughly 200+ uses on CO2.

Once you swap out the core you can fill the grenade with CO2 from one of the S-Thunder brand CO2 chargers or use the madbull one you might still have kicking around. Just slap it into your favourite 40mm launcher pull the trigger and fire away. Once the shell is fired to reset the shell to fire it once more just press the primer in and let it re seat to where it started.

Conclusion

I found this shell to be a very well thought out shell and continually had a smile on my face every time I fired it. However when on the receiving end of it I felt like I was getting hit by a good burst of rounds. This thing will be super effective in an urban setting. The three different body colors of the round allow for different loads. You can have .12gram pellets for spread or toss in some rubber balls for taking out a simulated tank. This product is great for the money and is almost half the price of its competitor.

Pictures

The grenade


A cross section showing the inner workings


The standard core


The CO2 Core

[wildcard]

the Co2 core look very similar to the madbull xp series nades, hmm got to get me some of these. If these thing held up under my abuse then I guess I'll look into upgrading my 108 and 204 stock

[Duckman]

at a glance they look like the mb multipurpose nades.

[apocolypse]

Anyone know where to get these in Canada?

[bean]

I should be getting info about a Canadian distributor soon

[apocolypse]

Sounds good.

[H1TMAN]

Im glad to hear someone is having good results with theirs because so far the performance of my Thunder grenades a very disappointing. Im using the madbull fill adapter and for some reason I cant seem to be able to fill my grenades over 600 PSI.

[bean]

Really what do they do when you fill them over. I was using an unregulated fill adaptor.

[H1TMAN]

I get a back splash just like when you fill a TM P226 mag and the air pressure inside the grenade goes down form there on very quickly.

[coach]

not to rain down on this review but a bit of constructive criticism:

the rubber slugs are a waste. a tissue paper/kleenex wad is better as it will start to break down come the first rain fall. how long will those rubber caps take to start breaking down?

Originally Posted by wildcard

the Co2 core look very similar to the madbull xp series nades, hmm got to get me some of these. If these thing held up under my abuse then I guess I'll look into upgrading my 108 and 204 stock

not that much of an upgrade if any! these thunder nades are the same as the xmpb4's. the ones you hate, lol!

cores look pretty similar. ignore the bottom part. only difference is that the MB version is a flat top.

Originally Posted by H1TMAN

Im glad to hear someone is having good results with theirs because so far the performance of my Thunder grenades a very disappointing. Im using the madbull fill adapter and for some reason I cant seem to be able to fill my grenades over 600 PSI.

are you using the 12g cartridges or a 20 oz or similar tank? 600psi is more than plenty

[bean]

The rubber slugs are just conviniant. I used to use tape on my madbull but I found the rubber slug to be more useful for me. Its all a matter of oppinion. My madbulls seals ate themselves fairly quickly on lesser power when I had it. Yeah I agree with you 600psi is more then enough.

[coach]

Originally Posted by bean

The rubber slugs are just conviniant. I used to use tape on my madbull but I found the rubber slug to be more useful for me. Its all a matter of oppinion. My madbulls seals ate themselves fairly quickly on lesser power when I had it. Yeah I agree with you 600psi is more then enough.

I guess it depends on how you use it. my xmpb4's have been used at 600-800psi regularly. only been lubed twice in 2 years. I'll need to service one of them and replace the valve (core) as it doesn't reset properly and is a bit twitchy. basically fired itself under fully auto with a stock WE PDW. however the other xmpb4 or kings had no issue with full auto fire.

[bean]

Perhpas I got a bad one. Mine were bought when the madbulls first came out. Regardless if these have the same general performance they are significantly less expensive.

[coach]

fair enough. be interested to see what an in country retailer charges for them.