Hi all,

Saw a PWS mk107 pistol at my lgs recently and I was wondering, since I know nothing about them, if it's possible to swap the under tube for the kak or phase-5 hex tube instead.

I've asked PWS this but it's the weekend so I don't expect to hear back quite yet. I'm also curious about changing muzzle devices and the overall ability to change or modify certain parts like the trigger etc.

I hate it when the case of the " I wants" kicks in.I actually liked it when I had a chance to hold it but the piston and proprietary parts had me hesitate for a minute before saying "ok". I've also gotta check with my local range to see if something like this is ok to run or if the noise will be too much of an irritance to other range members.  Has anyone run into problems running a sbr/pistol cause of excessive noise?

So between piston/di and 7" or 10.5" barrels and parts availability I've got some research ahead of me. Sad part is that by the time I make up my mind the dang thing will have been sold.

Either way I wouldn't mind hearing from those who have a PWS sbr or pistol good or bad.

Yes, that is very possible.i am running a phase 5 on mine. Using an H buffer.
I have replaced the hand guard with a longer model and installed a KX5

You said you replaced the handguard with a longer one, any issues with fitting with the piston system or is your upper DI?

No issues at all. I used a PWS piece, simply removed the screws at the barrel nut and replaced the tube/hand guard.
I do need to get it to a machine shop to have the new tube milled for access to the piston selector/plug

Doubletap......

That's the rig alright minus the kx3 and spikes lower. Still on the fence on this cause of proprietary parts. I think that's a stigma engrained or picked up from the Internet or maybe not. I've never shot anything shorter than a 14.5" ar and I'm wondering if anything else would be comparable, 454 casul, m1 garand? Is the flash and blast not worth it in a package this small?

With the right muzzle device, the flash and blast are greatly minimized

I got a great deal for anyone who wants a mk107 mod 1 upper new!

$150.......?

Pretty much sold on the mk107,though I think I'd rather have the 10.5" version but the lgs by me has the mk107 so that's what I'll go with. Depending on the amount of flash coming out the end of this rig, I may toss the kx3 on it but we'll see. Wish I could have found a di piston setup that was complete but no such animal exists besides building from the ground up.

A "DI piston system"?

Huh?   Direct impingement and piston systems are different animals.

I'd wait for the 10.75"  MK110

The Mk107 with a Knights triple tap is a pleasure to shoot!