Convert GHK Colt Mk 12 to Mk18

nikvanorton

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Can anyone tell me what bits I need to convert a GHK Mk12 into a Mk18. Obviously stock, handguard, barrel, but what other not so obvious bits do I need? Is it best to get them from Sixmm, WGC etc?
Any help appreciated. Thanks.
 
I'm far from knowledgeable on GHK though depending on the barrel nut you use, you may need a spacer for your outer barrel.

Regarding Sixmm, I would suggest you read the comments here so you understand the potential problems. I've been one of the more fortunate customers.

 
My self to save some faff , I would build a separate full upper or see what's about used so you have the option for a hot swap set.
Is your mk12 a collapsible stock or full stock?

My own golden rule is stick with the same brand or something listed made for that brand .

Upper parts should be depending on version of mk18.
Inner and outer barrel
Gas tube
Gas block/front sight
Delta/barrel nut + shims
Handguard cap ( mod0)
Crush washer and flashhider

You could even ask for a trade for your upper , but I would do face to face to make sure it's correct and fits

if it's a full stock , you would need
Buffer tube
Buffer spring
Buffer plate

I think that's it lol ( head still up my arse atm )
 
Can anyone tell me what bits I need to convert a GHK Mk12 into a Mk18. Obviously stock, handguard, barrel, but what other not so obvious bits do I need? Is it best to get them from Sixmm, WGC etc?
Any help appreciated. Thanks.
Samoon. As mentioned above, I’d pick up and build a 2nd upper. If your Mk12 has a solid stock you’ll need a buffer tube, spring and buffer as well as a stock.

Read nothing but horror stories regarding Sixmm.

Never had an issue with WGC but it’s been a few years since I’ve ordered anything.
 
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