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Sig MPX K 9mm
- Thread starter Tango down
- Start date
As with @bonifacio, I kinda made my own, though I went about it in a different manner; I purchased a 4.5" barrel from ILWT that has a built-in three lug adapter, and an adjustable gas plug from them as well. Mine's still a bit gassy when shooting suppressed (the only way I shoot it, as my 9mm can lives on this gun) at more "lively" rates of fire (I also installed a binary trigger).
Beyond that, my only complaint is just how quickly it'll chew through a box of 147 gr ammo...
Beyond that, my only complaint is just how quickly it'll chew through a box of 147 gr ammo...
Have one, love it. If I recall correctly, there are now at least 2 generations, be aware of which you get.
Also, Sig has long since decided not to worry much about creating the myriad products they initially claimed in support of the platform: lots of calibers, lots of barrel lengths, basically the lego of SBRs - none of which ever happened.
There was some issue a few years back about swapping the trigger voiding the warranty, I'm not sure where that ever went.
Mags are expensive, but well made and they hold up pretty well to abuse.
Mine runs an 8" barrel, I didn't have to mess with the gas system, but I did get an extended rail, so can run a nested can or no can.
The stocks are hit-n-miss, you might want to try to get behind a few before deciding what to get - that is if you plan to SBR it. If not, get the stabilizer like all the other fannybandits at the range.
No offense, fannybandits.
It is a very good platform for its intended purpose. I still prefer an MP5 just because I know it so well, but this is a good option that is 10% the price of an original MP5.
Last, I would not get a pistol caliber in a rifle platform to do any real work; however, this thing can be very compact and very useful for certain applications. Its strength is its size, keep that in mind when setting one up.
Also, Sig has long since decided not to worry much about creating the myriad products they initially claimed in support of the platform: lots of calibers, lots of barrel lengths, basically the lego of SBRs - none of which ever happened.
There was some issue a few years back about swapping the trigger voiding the warranty, I'm not sure where that ever went.
Mags are expensive, but well made and they hold up pretty well to abuse.
Mine runs an 8" barrel, I didn't have to mess with the gas system, but I did get an extended rail, so can run a nested can or no can.
The stocks are hit-n-miss, you might want to try to get behind a few before deciding what to get - that is if you plan to SBR it. If not, get the stabilizer like all the other fannybandits at the range.
No offense, fannybandits.
It is a very good platform for its intended purpose. I still prefer an MP5 just because I know it so well, but this is a good option that is 10% the price of an original MP5.
Last, I would not get a pistol caliber in a rifle platform to do any real work; however, this thing can be very compact and very useful for certain applications. Its strength is its size, keep that in mind when setting one up.
Got one coming in(4.5", Gen 2); I may hit you with a few questions one of these days, thanks.
Yeah, I noticed Sig dropping the ball on many "options" for the MPX...
I think the trigger issue arose as some were installing AR triggers that were not 100% compatible. Looks like Timney has a good one now, it comes factory from SIG on the latest MPX models.
Got a 4.5" Gen 2 coming in with 6 mags.
It comes with the sliding stock, which I'm kinda used to, as one of my service weapons was a Mat 49 with sliding stock. A bit different but similar concept.
Never shot an MP5 but always been impressed by the accuracy of that little gun, especially compared to our 9mm full auto.
Now, I have to ask this, even if I feel the bad jokes coming...; what is a "fannybandit" and what is a "stabilizer"?
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I have one. It's the Gen 2 and it sucks with Gen 1 magazines. I originally got it with the 4.5 barrel. With Gen 2 magazines and UN-suppressed, it was accurate and reliable.
When I put the suppressor on the short barrel, the accuracy went to crap really fast.
This guy had basically the same experience that I had. If I recall correctly, he states that if he had a Sig suppressor it might be more accurate. Well, I have a Sig suppressor and it didn't improve the accuracy.
I purchased the 8 inch barrel for the pistol and it shoots just as good with the suppressor on it as without.
The bottom line is if you plan on suppressing it, make sure you have the longer barrel. The short one sucks unless you are going to run it without a can.
When I put the suppressor on the short barrel, the accuracy went to crap really fast.
This guy had basically the same experience that I had. If I recall correctly, he states that if he had a Sig suppressor it might be more accurate. Well, I have a Sig suppressor and it didn't improve the accuracy.
I purchased the 8 inch barrel for the pistol and it shoots just as good with the suppressor on it as without.
The bottom line is if you plan on suppressing it, make sure you have the longer barrel. The short one sucks unless you are going to run it without a can.
I saw Mac's vid as well; planning on running it without a can but good info about the 8", thanks.
Sig brace = stabilizer, it is the homogay alternative to an SBR. A fannybandit is a homogay person that gives handjibbers to homeless men behind the dumpster near your local 7-11. These are industry-standard terms. And my MPX is SBR, for any homogays that might want to know...
From what I can tell, the gen2 was supposed to solve problems that some - but only some - had with the gen1s. My gen1 has run like a scalded dog since day 1. It had a few hiccups during breakin, but has since been 100%. It is run suppressed almost exclusively. I just ordered a 4.5 barrel and am now wondering if I should cancel that order, if the accuracy will go to hell suppressed.
Roger that; I know now why the homeless dude behind the 7-11 was smiling. Yeah Mac's video brings up questions; do not know if he got it solved with Sig.
If you ordered your MPX recently you will probably be getting the new Gen 3 model. It is pretty much exactly the same as Gen 2, but the rear Recoil Spring Plate has a tab coming off the back and will not work in Gen 2 lowers. It also supposedly has a better barrel lockup system, but gen 2 barrels are compatible. Only reason I know, is because I had my local shop order a new upper and bcg from Sig for a suppressed short barrel and unsuppressed long barrel competition setup. It came in with the newer Gen 3 upper and parts.
All that being said. Since you are ordering a complete pistol, you will be fine and not really need to worry about the gen models. Just don't run gen 1 mags in it.
All that being said. Since you are ordering a complete pistol, you will be fine and not really need to worry about the gen models. Just don't run gen 1 mags in it.
I have the Gen. 1 in homogay retractable SB brace. Eats anything I have offered, and is smooth as a church fart, with super mild felt recoil. I also have heard of reported problems, but mine is solid and reliable. I like it a lot.
I was ready to get one when they announced this years ago. Announcing there will be a Gen2 as the first ones were being shipped to stores was a huge WTF in my book. And Sig admitting mags might have issues when in a different gen gun. I decided to pull a wait and see since Sig has pulled make early adopters of our products beta testers. Some of it was silly mistakes, like the charging handle chewing up the back of the lower. But what happened to all the promised features? Now I am glad I decided to pass on the MPX. It looks like a solid performer now, but between lack of options both in what is available, aftermarket parts, and Gen compatibility, I will pass. Plus Sig raised the price a lot about a year after introduction, and now they are closer to HK SP5 than BCM AR-15s in prices. And I would rather get the MP5...
So if this SIG is not an optimal pcc then what other options would be recommended? The scorpion seems decent.
Love mine supressed. Bit heavy for a 9mm PC, but I do not mind as it helps follow up shots. Hate the AR tear charge, really wish they went with side charging as the charging makes the receiver taller than it has to be. I have the 4" barrel and with the supressor still fits into a computer case.
You can. Thing is the diameter of the wide open setting is larger than what the barrel is tapped for. You should never really need to use that setting anyway using very reduced loads
But theh are. If you talk to anyone who owns a current gen they love them. Some issues plagued the first gen but I think many new weapon systems have those type of issues. Instead of leaving them like it was they fixed issues. But I can also understand being one of the first owners and being pissed off that your outdated system sucks.
It's a used Gen2 (with keymod) I took on a trade; did not shoot it yet. Will try it next week; seems a bit stiff (action, trigger) but it did not see much action, so even though I have zero experience with this specific weapon, I assume everything needs to settle some. Cleaned and lubed it so it is ready to go.
How would you compare that with the cheaper scorpion, more expensive b&t or the ptr mp5? Trying to get something my wife can handle and a short PCC sounds like a good option.
It's the best Factory PCC I've ever seen. Some people like the cmmg better but i don't. It is one of my absolute favorite guns to shoot. I've also changed quite a few things. Mag well, gas block, CH, stock, HG. Wifey absolutely loved it. It's single-handedly responsible for getting into firearms
I also really like the Sig MCX. Like I said there's been issues in the beginning but the current generation I feel like is one of the top platforms available. A lot of people agree just look at YouTube reviews on the virtus and mix k
I have an early Gen 2. Orginally it was 8" pistol so I form 1'ed it and had the barrel cut to 4" and tri lugged as well as adding a Next Level Armament gas block and charging handle. I run it suppressed all the time and at nearly 10k rounds have had no issues...(knock on wood that i have not jinxed myself!). Set up with Scalar works rmr mount and rmr06.
You guys should become Sig salesmen. Getting my wife into firearms would be a huge selling point. She didn't like my old m&p9 so I am hoping getting her on a PCC platform will allow her to enjoy shooting something besides .22 short.
And for my own selfish reasons if she likes shooting then I will get yelled at less for buying gun stuff.
And for my own selfish reasons if she likes shooting then I will get yelled at less for buying gun stuff.
Glad to be of assistance! I completely understand your position and wish you luck. About the MPX, there is a ton of negative stuff out there but I will say again, I have had no issues and will add I have only broken it down to its component level to clean 3 times.... I am of the opinion, and yes my opinion alone and I know it stinks.... that far too many people change internal parts(especially for aftermarket gaming components) and over clean them resulting in unintended consequences...
I would agree with that for home defense purposes. It is why my glock has its factory trigger.
Many people also just dont know how to do basic maintenance or troubleshooting. Have seen issue with people loading 9 too long, to short, didn't torque to bolts down correct.
I saw someone up top recommend that Tacom buffer thing. Don't do it. I threw mine in the trash. You can't separate the upper and lower and it does nothing for recoil on mitigation on something there's not recoil at all. I mean that's the point in these s right?
So far the MPX (Gen 2) has 250 rounds, did a good cleaning yesterday including piston.
No issue, decent grouping @ 25 yards after zeroing red dot (you can see the "climb" on pic). I understand why Sig went with Timney on the Gen3, not impress by the Gen2 factory trigger but everything else is AOK.
No issue, decent grouping @ 25 yards after zeroing red dot (you can see the "climb" on pic). I understand why Sig went with Timney on the Gen3, not impress by the Gen2 factory trigger but everything else is AOK.
