Marushin G21 Shell Ejecting Upgrade Advice

[stealthferret]

Hi,

I've just bought a second hand Marushin Dual Maxi G21 Shell Ejecting GBB, it works fine (so I've been told, not tried it yet) but it does have a cracked slide.

I was wondering if anyone can offer their experience as to what upgrades would improve the accuracy and longevity of this gun?

I definitely want a new black metal slide with full trademarks (I think RA Tech looks the best but Shooters Design and Airsoft Surgeon both look decent too) and a metal outer barrel to go with it. Not sure what to do internally?

Is the 8mm > 6mm conversion recommended? RA Tech shells? What about valves etc?

Given this gun has been off the market for a long time tracking down parts is likely to be difficult but it would help if I knew exactly what I was looking for!

Any help would be much appreciated.

Cheers

[chaz_r33_gtr]

Re: Marushin G21 Shell Ejecting Upgrade Advice

I got the 6mm cz75 she'll ejector and in terms of accuracy..the hop rubber (if yours has one) is rubbish doesn't correct the random spin imparted on the bb by the rubber bb retaining ring in each she'll. I ended up rhop'ing mine for 0.3g 6mm bbs and accuracy was reasonably good after that. I wouldn't use green gas propane or equivalent in it either if my cz75 is anything to go by. It caused my slide to crack at the rear and the valve lock in the hammer mechanism to snap rendering the blowback to be non existent.

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[stealthferret]

Re: Marushin G21 Shell Ejecting Upgrade Advice

Hmm, wonder if that's how it got the cracked slide originally?

New hop rubber - check.

Thanks for reply.

I got the 6mm cz75 she'll ejector and in terms of accuracy..the hop rubber (if yours has one) is rubbish doesn't correct the random spin imparted on the bb by the rubber bb retaining ring in each she'll. I ended up rhop'ing mine for 0.3g 6mm bbs and accuracy was reasonably good after that. I wouldn't use green gas propane or equivalent in it either if my cz75 is anything to go by. It caused my slide to crack at the rear and the valve lock in the hammer mechanism to snap rendering the blowback to be non existent.

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[chaz_r33_gtr]

Re: Marushin G21 Shell Ejecting Upgrade Advice

Yeah might have been how the slide cracked. Regarding hop rubber.. they don't have a traditional hop rubber..it's just a small patch of rubber which protrudes through a hole a cm or two down the barrel. This doesn't really work and you would need to drummer a proper hop window and then fit an rhop patch and tune it to the bb weight you want to use

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[stealthferret]

Re: Marushin G21 Shell Ejecting Upgrade Advice

So, had a go at cycling it by hand earlier and what do you know, the cracked slide became a two part slide! Pretty sure the internals are okay, just need to get a new metal slide to mount them in...

Found a small L shaped piece of metal on the floor, not sure where that's come from so I am hoping whomever I get to fit the new parts will know?!

To that end I have found a metal slide and outer barrel online, an upgraded recoil spring and guide and upgraded 8mm shells as well as two additional magazines. Still looking for an upgraded shell hook and a 'high flow valve' (?) which I saw had been installed to one of these in the past but I have no idea what sort of valve I need.

I also found an 8mm-6mm conversion kit but they don't sell the shells separately and I can't really justify spending nearly $100 just to have three mags worth of 6mm shells.

Speaking of mags, I have noticed that it's pretty tight fitting, it takes a little more effort to get it to seat properly and it simply wont fall out when the mag release is pressed, you have to pull it out. Do you think I would be best sanding a little off the inside of the magwell or off the outside of the mag (pretty sure its a plastic type substance)?

I'll note down your info on the hop up - seems a little too technical for me but something I might provide to whoever does the rest of the work.

Cheers!