Thanks in advance.

I'd love to have a QD barrel system on my build.

I saw the YouTube videos on the CMMG system, but I guess that has not come to market.

Anything similar currently available?

G.

haven't seen CMMG's but this is available

http://www.mapartsinc.com/productsDetail.asp?id=1415

Lewis Machine & Tool Monolithic Rail Platform CQB

or

Rifle MRP

This place will convert any AR15 barrel to fit an MRP.  If you wanted to get a Wilson Combat 6.8 or Noveske 300BLK you'd pay them to do the machining and get it back to you so that you can run any caliber you want.

Now that is too damn cool!

These guys have a different approach. Change calibers in a minute.

MGI

forgive the new-b question, but how is this any faster then changing a barrel the standard way?  looks like the gas system still has to be removed. would you still need a vise and upper vise block?
torque wrench?

The GB doesn't need to be removed; it can sty attached to tge barrel and pulled directly.  All of the product photos show the GB still attached.

If you're asking about the system I posted a link to, the gas tube does not need to be removed from the barrel once the collet ring is installed. The larger, nut with the teeth stays with the receiver, and the inner collet ring replaces the standard barrel nut and stays with the barrel.

To add or remove a barrel all you do is loosen the  inner collet ring with the supplied wrench and slide the barrel and gas set up away from the receiver. A dab of thread locker helps keep the toothed nut aligned with the gas tube hole in the receiver (it's not necessary but make the whole job a bit easier).

No, you don't need a vice and receiver clamp to change things since you only need about 30-40 lbs of torque to hold things together,  it does however make the swap easier than trying to hold everything together with just your hands.

I have removed and replaced a barrel at the range to see if it could be done and if it changed zero (it didn't), but I had a friend hold the rifle, just so I could use two hands on the wrench to prevent any slippage that could of scratched things up.

The only downside to the system is you have to be able to get to the barrel nut area to do the swap, so this rules out free float tubes, unless you can find one that would clamp onto a factory style barrel nut and has a removable section so you could access the collet ring with enough room to swing the wrench

I thought this would be a nice idea.  Swap out say a 7.62x39 barrel for a 5.56 etc.  Or even a 20" barrel for a 16".  
You get to not buy optics twice, sights, upper, CH, etc.  

But honestly if all your stuff is zero'd for one barrel.  Unless it's the SAME barrel you're putting in, chances are you are going to have to readjust everything anyway.
Might as well just build another upper and push two pins.

Unless maybe for half a season you shoot in volume say a 5.56 rig, then swap it out for a 6.8 setup to hunt.  
Re-zero, hunt, swap back.  

I just don't see it being that useful.  Another upper rec is only $100.  Charging handle $20.  
You're going to end up with gas blocks, tubes, etc that stay on the barrels.  Different BCG's... So add a rear sight...

Or be constantly moving all of your sights/zero around for each barrel.  

Plus if that little lock ring comes loose doesn't it present a risk of changing head space?  
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