Why hate the keymod when you can cover them up with low pro rail covers:
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Ooo.. Me likey. On another joyous note, my MPX will ship tomorrow. Hopefully paying for the expedited shipping gets it here for the weekend, though I doubt it..
Why hate the keymod when you can cover them up with low pro rail covers:
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Are >5 rounds options available?
Looks great.
No, they do not use sig pistol mags so they are currently limited to 5 rounds as a semi-auto center fire.
Big mistake IMO.


I will likely try to find one of those nice skeleton stocks that the MCX has.Whoa, wait. I didn't realize this was a thing. How does the verification process work?
It was restricted not due to it being a pistol, so just send it to a qualified gunsmith who offers barrel work and re-verifying service.
Many use Herron Arms Ian, he did my ACR.
Good to know. I knew they were restricted based on barrel length, but didn't realize that they could be reclassified that easily. I've been toying with the idea of buying a 12.6 pistol (which I'm not allowed to own) but having it rebarelled to a restricted length. I was under the impression the process took forever .
Thats terrible accuracy... but sweet gun none the less! looks very high quality. hopefully you will be able to print better groups with it in the future though, my JR consistently shoots atleast 2" @ 50 if not better
Woohoo! Here it is! My nice newly non restricted MPX came in the mail today, so obviously I had to take it out for a shoot. I mounted my Aimpoint Pro and after a quick sight in, did some 50 metre work.
My key take aways are:
-Herron Arms does great work. Seriously, the barrel looks amazing.
-Trigger: decent, not amazing though. It is smooth, but heavier than I thought it would be. Slight take up, then a wall. You know when it will be firing, so that is nice and predictable.
-Recoil: What is this recoil you speak of? I don't think the sight moves more than a few inches off target when I shoot. It is like a .22LR. But actually, I think it recoils like a .22.
-Quiet: My goodness, I could have sworn it was suppressed. Obviously I had hearing protection on, but I have a feeling if I were to go varminting with it and forget to muff up before shooting, it wouldn't be a terribly regrettable experience.
-Accuracy: This thing is not a precision rifle, that is for sure. I do wonder if my targets had anything to do with such a long barrel, and the gas system being so far back. I will try and chrony it when I can, but my guess is there is some pretty extreme variation to my muzzle velocities. I only had PMC Bronze ammunition to shoot, I'm looking forward to trying some others. I was shooting prone off of a solid rest.
-Magazines: Among the nicest I have, Lancers are well built. However, IRG, please pin them slightly lower. There is no way I could seat a 'full' mag on a closed bolt. There is absolutely no wiggle room with that 5th round in, it does not push a millimetre further than it has to.
-Collapsible stock: Pretty cool little stock, though honestly it does not really suit the carbine role this gun is taking on. Also, my scraggly beard hairs get caught in it.I will likely try to find one of those nice skeleton stocks that the MCX has.
-Weight: There isn't much weight, at all! Even with the carbine length handguard and 18.6" barrel, I'm pretty sure my preemie newborn weighs more. I will weigh on my newborns scale when I get a chance.
-Control: The ambidextrous controls are great. I am a lefty, so I really appreciated the well placed (AR-like) controls. Easy to manipulate. I'm not convinced on having an AR-15 type charging handle, but, whatever. I have to leave the bolt open anyways to seat the next mag, so it's not like it gets used.
All in all I am very happy with this gun, and if you are interested in a non restricted MPX, I would highly recommend both IRG (they have the carbine handguard version) and Herron Arms for the conversion.
And now for the pics. I had some nice canola fields nearby, so thought I should copy Arm & Gun and do a photoshoot like him, albeit with a crappier camera. I've also posted 3 five shot groups. They are all between 4-6" at 50 metres. I will try some different types of ammunition, and different projectile weights, and see what it likes best. Also pictured is a comparison with my Modern Varmint. Pretty similar lengths, but overall the MPX still feels tiny compared to the MV.
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If you are wondering about 9mm carbine accuracy, I can attest that my three restricted carbines (B&T TP9, RRA LAR9, and a Kriss 9mm) as well as my only closed-bolt SMG (HK MP5) all print a ragged hole at 25m off-hand and less than 2" groups at 50m rested. Your accuracy from a long-Barrelled SIG MPX is pretty disappointing in comparison. Hopefully a different ammo selection will improve results, otherwise I'm not sure how I would proceed. Best of luck with a resolution!



























