I messed around with the pistol version today.
If purchased I'd SBR it so I could have an actual stock & make use of the extra barrel length. It would be an HD gun. Most likely suppressed.


Sell me or sway me away from it!

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500 rounds last Saturday with a new MBT trigger installed.....so much fun.  Way quieter than my pistol ARs and no recoil.  

I have a few Gen 2s and have no complaints.  I also have a couple scorpions and they are just as much fun but half the price.

If you get a MPX pistol, put a retractable SB brace on it, just like in the picture above.  It is amazing.

Cz evo mags are cheaper.. That's all I got, looks like fun.

CZ will probably support their firearm in 5 yrs.
SIG will probably not be supporting their firearm in 5 yrs.

Just read thru the SIG subforum.

Can you elaborate a bit?


But there is a reason this gun kind of flopped. Shooting one suppressed is like kissing the exhaust port of a weed-wacker.

I have a gen 1 SBR. It has given me no issues and I enjoy shooting it. In hindsight, I should have left it as a pistol and used one of the newer braces. I'm at 2 months waiting on my 5320 to come back so I can't take it across state lines.

I'm a bit concerned about Sig's long term support so extra parts will be on my shopping list just in case. It doesn't appear that the caliber conversions will be happening either so that is another negative.

The mpx didn't cure my MP5 itch so I'll end up with one of those anyway.

At this point, I could almost have a Scorpion pistol and a Scorpion SBR for what I've got tied up in this one MPX.

Fuck, I was really looking foreword into one in 10mm, .40, or .357SIG

My mpx. Barrel cut to 5 inches with a 3 lug installed over the barrel vs on the end(mp5 style). Gun refinished in burt bronze. Has a larue trigger, trijicon mro, a next level armament ambi charging handle(this came in yesterday, from dry firing and cycling it seems to be a lot better than stock), sig stock, etc. TSC machine did the refinish and barrel chopt. Mike actually seemed pretty impressed with the gun

Both it and the evo have aftermarket options now. The sigs stock trigger is bad, the evo's if horrible as is its safety as it is too long and can dig into your hand. The early evo mags were complete junk but that seems to have been fixed. MPX mags are not cheap but you can find them on sale. They are lancer mags and from my experience have been great.

Sig hasn't done the best job supporting them. My understanding is replacement rails from them are finally available as are some third party ones. I haven't seen the caliber conversion stuff although I didn't really care about that unless they can fit 10mm into it.

I've been really happy with my mpx and am glad I went with it over the evo. Larue kinda challenged someone to break his trigger in one which is why I bought it although you have a few companies making triggers specifically for it now. The gun gives me ar-15 style ambi controls so it works just like my ar-15. I will say with how mine is setup some 9mm ammo can get pretty gasy. I can't really speak to the stock barrel length as it was shot once as a pistol to verify function and the barrel was cut before the form 1 was ready. Mind you the gun runs everything I've tried through it. I found it likes the heavier ammo better as far as blowback. I'm hoping that next level armament hander will help here as its charging handle grips are a lot thicker.

I'd buy the gun again and want a mcx sbr now. I'm really happy with my gun.

I sort of like mine but it was an absolutely retarded decision to design the hand guard in a manner where it is press fit on the upper and held in place by the pivot pin. Not that the MPX should be 1 MOA accurate at 100 yards using only iron sights, but knowing how violent a gun firing is, it isn't confidence inspiring.

I can think of 20 better ways to do the hand guard. It is almost as if Sig wanted a completely proprietary system so that they could capitalize on the aftermarket.

Another point to consider... Shooting the MPX suppressed directs jets of gas straight into your eyes.

Other than that, I think it handles and points well.

Anyone make a gasbuster handle for it yet?

I guess I'll be that guy and say get an HK Mp5 clone instead   

My experience with the gun is that it will run pretty much any ammo but you can really drop the gas in the face by finding out what the gun prefers. Mine really does seem to run better with 147gr ammo but even between the same ammo weights I've seen big differences depending on who made it.

I was kinda hoping the next level armament handle would help as it is a lot thicker but I read on here that they don't claim it does. I've gotten mine in and the lifter thing that takes away a bunch of slop in the charging handle it comes with and am looking forward to the range when I finally get time. Sadly the next few weekends I'll be busy.

I have a sp5k pending that tsc machine swapped a b&t barrel onto and installed a paddle mag release on. I've also ordered a zenith full sized mp5 clone that I'll form 1 after testing(I really wish hk would import the full sized mp5 clone in as a pistol or even in hk94 style).

I also have a kriss vector in 10mm pending. I'm really looking forward to shooting it.

Gen 1 mags are 20 bucks.  Next level armament makes ambi handle with block that eliminates original sloppy handle.

A scorpion is half the price and just as fun. I couldn't justify something in 9mm that expensive.

I've been quite happy with mine so far. The gas will choke you up if you start doing mag dumps, but it's not that bad overall. I'm using the Hybrid with an ASR flash hider.

I like mine (SBR). Shooting suppressed hasn't seemed nearly as bad as some here have said. There's maybe a little gas in the face, but I've shot ARs that were much worse.

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Can't 

I have a CZ Scorpion. Zero gas in the face when suppressed. It is super well engineered and very well made. I am extremely happy with mine. I picked up an FDE version for $695 new on Gunbroker. Once I SBR it and pick up the stock, I am still almost at half of the MPX pistol out of the box.

If you're willing to spend the coin, go with an MP5 clone, especially if you want to shoot it suppressed. Otherwise the EVO is just as much gun for a lot cheaper.

I love my suppressed Scorpion.

I will go the other way, and say a 9mm AR build.

With a PDW style stock, a URX style handguard, and a lower designed for 9mm mags (vs a 5.56  receiver set up for 9mm), you can get something that looks pretty close.

Plus, its an AR so you can piece it together as funds allow and change parts around if you get bored.

A 9mm AR is still a direct blowback gun though.

And so is just about every PCC design in the last 100 years. A few exceptions like the MP5.

About sums it up for me with Sig for anything other than a 220/226/229

http://www.ar15.com/forums/t_6_45/478361_why-was-the-SIG-556-discontinued-.html

Yes, I have owned two of their rifles.  NEVER again.

That said, do I think the MPX is a bad rifle?  Heck no.  However, I have complete confidence in Sig that they will inevitably screw it up one way or another.

We have a SBR'd gen 1 as a rental gun. After 2,000 or so rounds things started to go bad.  Multiple hammer pins broke, then when taking apart to clean one day about every spring/small part was broken. Took a month before Sig would RMA it. They weren't even sure the differences between the generations.

Got the gun back in decent shape after another month. They replaced just about every part they could. Sig even told us that they are not confident in the gun.

We will see how long this lasts...