9x19 PDW

[Lyapunov]

Hi guy, new member here who just escaped into free America and am looking to use some of his signing bonus for a PDW. This will primarily be used inside the house, suppressed. I choose 9x19 because I already load 147gr for my pistols and it doesn't have as much concussion inside.



Colt vs. Glock

• Is there an obvious advantage to either I'm missing? I don't have a Glock, and $ is similar between metalform and Glock OEM. I'm thinking that the alternating-feed of the Colt is more reliable and easier to load than the single-feed of the Glock?
• I'm a lefty who has trained himself to use a right handed AR. For mag change, I would grasp the magazine with my right hand and depress the mag release with my thumb while pulling the magazine out. Will the slightly raked angle of the Glock mess me up?
• I desire a last round bolt hold open. Colt pattern seems to be solid but Glock pattern is hit or miss on that front. Truth?
• Do the mods made to a Glock bolt generate any new stress areas that would degrade service life?

Dedicated Lower vs. Mag Block

• How easy is it to change from 9mm to a Mk18? I don't see myself needing/wanting a 5.56 or 300BO SBR, but I don't mind the option for giggles later on.
• Do mag blocks function like a mag well funnel and help speed up reloads?
• Are there advantages to Sten/Sterling mags that would tip the scale towards a mag block?

Lower Parts

• I've read the blowback action beats up the hammer. Is there a brand you guys recommend?
• Should I get anti-walk pins or something similar?

Upper

• Given that I'm a lefty, will I need a Colt style upper to deflect the brass/gas?
• What combination of bolt/buffer/spring do you guys recommend? I primarily shoot 147gr but ability to use 115gr stuff is nice.

Barrel

• What length/brand barrels do you guys run? I'm thinking ~5" would make it pretty handy and won't loose much ballistics given the fast powder.
• What muzzle device do you recommend? I want to share the suppressor with a pistol (an HK P9S that is begging to be hushed).
• What suppressor do you recommend? I would gladly trade db or bulk as the primary objective is not to be splinter cell silent, but to protect my hearing. 147gr is primary and I have no requirements to suppress 115gr (unlike MP5SD).

Uzi/MP5

• All said, would I be better served with an Uzi/MP5? I know HK's reputation, but I'm not sure that translates to the off-brand clones. Same with the open-bolt real Uzi vs. closed-bolt copies.

Here is what I'm thinking for now (sights will be HK style drums). Appreciate the help.

[WickedWillis]

Have you looked at the CZ Scorpion Evo? It has almost everything you are listing here and they are now shipping the 922R compliance kits to SBR them. Check out Plouffdaddy's video on it;

https://youtu.be/aAR649A2RSQ

[glocktogo]

The EVO should warrant a serious look IMO.

[Slick88]

That scorpion Evo is bad@$$

[JBecker 72]

That scorpion Evo is bad@$$

I want one.

[turnburglar]

Personally I would NEVER use a pistol caliber, when a rifle caliber is available.

With that said I'd look at the cz scorpion before Lego'ing a 9mm AR.

[Lyapunov]

Ha, I totally missed the Evo. That looks to be it for a 9x19 PDW. I'll always lust after a real deal MP5k, but I'll settle for the Evo for practical use.



WRT "rifle caliber", I take it you're referring to the 300BO? If so, what is the muzzle velocity of a 220gr subsonic load out of an 8" barrel? Wiki only lists the 16" numbers. I'm open to the idea of a Honey Badger type PDW, but I want to know it is worth it. As I see it, subsonic 300BO from a 16" barrel is basically a 45+p. And with a PDW sized barrel, I'm guessing it'll be comparable to a 45ACP? I am personally comfortable with a 9x19 over 45ACP in a pistol.

300BO, 220gr, 1010ft/s, 16" barrel
45 +p, 230gr, 1000ft/s, 5" barrel

Since this will be used inside the house only (with occasional carbine matches to keep myself sharp), I don't have requirements for a 300yd shot (thus, supersonic loading of the 300BO). I think that negates the biggest selling point of the 300BO?

Can the suppressor for 300BO be shared with 308? I'm working on a 308 18" rifle, and while I don't see the need to ever suppress a 175gr 308, more options is always better.

[cgjane]

The good thing about SBR ing a lower is that it's an SBR for any caliber.

[HardToHandle]

I support the OPs analysis. 9mm is viable in a SBR, offering low blast and a lesser signature in enclosed environments.

I have a dedicated Glock lower. It works, but my limited experience with the traditional Colt dual feed says that is a great choice. My Glock lost is reliable, but required the modified bolt and lack of BHO means it is has a slightly different manual of arms from my 5.56 SRs.

Not a lefty, but I would want a blast deflector, especially if going suppressed. It is blow back but when I run wet, thereis generous distribution of black goop.

[JBecker 72]

Saw the CZ in person yesterday, but didn't handle it or think to check price. But it looked great.