SIG SAUER MPX (Update: Exclusive Non-NFA version P7)

March 12, 2016, 06:08 PM

You can shop for me anytime. I'd have been thrilled at the $1209 price.

March 12, 2016, 07:12 PM

g8rbreath

I always check slickguns for lowest price. I buy from site that has it in stock on my MasterCard then goto lowest price website to get price difference. It doesn't matter if it's in stock or not, they just want to see a copy of the advertised lowest price. So you can buy it for $1,500 but if you see it for 1,000 you can get a check for difference. slickguns MPX

Mastercard price protection

March 13, 2016, 06:23 PM

Dwill104

quote:
Originally posted by FrankMoses:
Well, after nearly a month of owning an MPX-C, I was finally able to get out and shoot it today. Illness and busy weekends worked against me.
Overall, it was a very positive experience, but it started out badly. The first round or two from the magazines I stuffed full of 30 rounds a few weeks ago to compress the springs a bit would not reliably feed. They got the bullet in the chamber but the bolt wasn't fully closed. Click. After clearing a couple of rounds, it started to go bang and never stopped. No failures of any kind, other than the first round, actually first two rounds, from the magazines. When I started loading them with 25 rounds, there were no problems at all. Not sure what that was all about.
Also had to lower the front sight a lot to get it where I wanted at just 10 yards. But all the time it was cutting out one hole groups from the sandbagged front end rest. Not a huge fan of the factory sights, but even with 65 year old eyes, they did the job just fine. Offhand I was able to keep 50-60 shots in a lemon sized hole at the same 10 yards, even when shooting fast. The reset is superb.
I'll run some pictures out at some point, as I installed an adapter that now holds a buffer tube and a Magpul SL stock. Also put the Magpul SL grip on the gun, as I have gotten to like the more vertical angle.
Other than the unwillingness to feed the first couple rounds out of the fully loaded 30 round mags, it was all I could hope for. Hopefully that is just a magazine spring issue, and under loading them "solved" the problem.

Same exact experience with my first MPX Carbine outing today. Two FTF on a full 30 rd mag. Round fed, but bolt stopped short of being closed. Tried 29 rounds, but it was hit and miss. 25 rounds worked like a champ. Other than that, which I'm sure is a mag issue, it ran great. Even didn't mind the trigger, which didn't feel as bad during actual firing as it did during dry firing. Sig and Lancer need to get a grip on the mag issue.

March 13, 2016, 07:22 PM

Dwill104

quote:
Originally posted by dwd1985:
quote:
Originally posted by Dwill104:
quote:
Originally posted by FrankMoses:
Well, after nearly a month of owning an MPX-C, I was finally able to get out and shoot it today. Illness and busy weekends worked against me.
Overall, it was a very positive experience, but it started out badly. The first round or two from the magazines I stuffed full of 30 rounds a few weeks ago to compress the springs a bit would not reliably feed. They got the bullet in the chamber but the bolt wasn't fully closed. Click. After clearing a couple of rounds, it started to go bang and never stopped. No failures of any kind, other than the first round, actually first two rounds, from the magazines. When I started loading them with 25 rounds, there were no problems at all. Not sure what that was all about.
Also had to lower the front sight a lot to get it where I wanted at just 10 yards. But all the time it was cutting out one hole groups from the sandbagged front end rest. Not a huge fan of the factory sights, but even with 65 year old eyes, they did the job just fine. Offhand I was able to keep 50-60 shots in a lemon sized hole at the same 10 yards, even when shooting fast. The reset is superb.
I'll run some pictures out at some point, as I installed an adapter that now holds a buffer tube and a Magpul SL stock. Also put the Magpul SL grip on the gun, as I have gotten to like the more vertical angle.
Other than the unwillingness to feed the first couple rounds out of the fully loaded 30 round mags, it was all I could hope for. Hopefully that is just a magazine spring issue, and under loading them "solved" the problem.

Same exact experience with my first MPX Carbine outing today. Two FTF on a full 30 rd mag. Round fed, but bolt stopped short of being closed. Tried 29 rounds, but it was hit and miss. 25 rounds worked like a champ. Other than that, which I'm sure is a mag issue, it ran great. Even didn't mind the trigger, which didn't feel as bad during actual firing as it did during dry firing. Sig and Lancer need to get a grip on the mag issue.

Stiff mag springs when new is, IMHO, normal and a good thing. The mags feed reliably once broken in, and I would much prefer to have to break in a magazine then have a magazine with a weaker spring from the get go.

There are dozens if not hundreds of mags made by a ton of manufacturers that feel full capacity straight out of the box and don't have springs that need to be broken in. I've had no problems with brand new Colt SMG mags, factory UZI mags, or MP5 mags if we are talking 9mm long gun mags. Don't know how others feel about having to "break in" every single new mag they buy before it feeds reliabily, but that seems more like making excuses for a poor design than a good thing to me.

As far as a "weak spring" goes, not sure how having a too strong spring that needs to be weakened is better than having a spring that is the proper strength from the get go.

March 13, 2016, 07:47 PM

FrankMoses

X10 on the " break in the mag" thoughts. Would Magpul be selling magazines faster than hot dogs at a ball game if you had to dick around with them for Lord knows how long?
Can't wait for them to start supporting this system, assuming they will.

March 15, 2016, 08:39 AM

ivy6t5

If and when the caliber exchange kits become available, does anyone care to share what caliber and barrel length you prefer and why? Thanks for the input!

March 15, 2016, 11:23 AM

johntsi

All 12 of my gen 1 mags have fed reliably from day one.

March 16, 2016, 04:47 AM

RichardC

What's the scuttlebutt on 357 Sig versions?

March 16, 2016, 10:59 AM

Cntrl23

I'm looking forward to getting the .40 Caliber Exchange kit with an 8" barrel. It will compliment my 4" 9mm barrel very well, and I currently have a supply of .40 on hand that I only use in my Glock 23. Plus I'd assume I would only need to purchase the .357 Sig barrel and not another kit IF I wanted that capability down the road.

On another note, my credit card was just charged for a Sig keymod foregrip with hand stop (GRIP-HS-KEYMOD-BLK) that I ordered from Sig CS at the end of January. I had a 4.5" Keymod K Handguard on that order as well, but wasn't charged for that yet.

March 16, 2016, 11:46 AM

quicksilvergoat

quote:
Originally posted by Cntrl23:
I'm looking forward to getting the .40 Caliber Exchange kit with an 8" barrel. It will compliment my 4" 9mm barrel very well, and I currently have a supply of .40 on hand that I only use in my Glock 23. Plus I'd assume I would only need to purchase the .357 Sig barrel and not another kit IF I wanted that capability down the road.

On another note, my credit card was just charged for a Sig keymod foregrip with hand stop (GRIP-HS-KEYMOD-BLK) that I ordered from Sig CS at the end of January. I had a 4.5" Keymod K Handguard on that order as well, but wasn't charged for that yet.

I was told mine would ship today. Haven't seen the charge yet but hope it pans out.

March 16, 2016, 01:01 PM

terry6v

I have a question about the 3 lug adapters that I can't find searching. I just got the 13.5x1 3 lug adapter from hkparts. It looks like really thin metal. There is no extra spacer to accommodate for the larger diameter threads. It looks like they just made the metal really thin to get the threads inside the same outer diameter . While this keeps the original look and length, it makes it look really flimsy. Has anyone used one from them? From reading I can gather that TROS are better if you can get one. I was just hoping to get some feedback from somebody that has already shot with one. I don't want to mess up a new can. Thanks

March 16, 2016, 01:37 PM

LDD

quote:
Originally posted by terry6v:
I have a question about the 3 lug adapters that I can't find searching. I just got the 13.5x1 3 lug adapter from hkparts. It looks like really thin metal. There is no extra spacer to accommodate for the larger diameter threads. It looks like they just made the metal really thin to get the threads inside the same outer diameter . While this keeps the original look and length, it makes it look really flimsy. Has anyone used one from them? From reading I can gather that TROS are better if you can get one. I was just hoping to get some feedback from somebody that has already shot with one. I don't want to mess up a new can. Thanks

I haven't seen the HKparts.net 3 lug adapters, but if you need a TROS one, send me an email--my shop carries them.

March 16, 2016, 01:47 PM

SigRocks

quote:
Originally posted by terry6v:
I have a question about the 3 lug adapters that I can't find searching. I just got the 13.5x1 3 lug adapter from hkparts. It looks like really thin metal. There is no extra spacer to accommodate for the larger diameter threads. It looks like they just made the metal really thin to get the threads inside the same outer diameter . While this keeps the original look and length, it makes it look really flimsy. Has anyone used one from them? From reading I can gather that TROS are better if you can get one. I was just hoping to get some feedback from somebody that has already shot with one. I don't want to mess up a new can. Thanks

The TROS adapter is definitely a good one. I have the one from Griffin Armament, and I'm very pleased with it. It also has wrench flats for installation/removal.

March 16, 2016, 02:12 PM

terry6v

quote:
Originally posted by LDD:
quote:
Originally posted by terry6v:
I have a question about the 3 lug adapters that I can't find searching. I just got the 13.5x1 3 lug adapter from hkparts. It looks like really thin metal. There is no extra spacer to accommodate for the larger diameter threads. It looks like they just made the metal really thin to get the threads inside the same outer diameter . While this keeps the original look and length, it makes it look really flimsy. Has anyone used one from them? From reading I can gather that TROS are better if you can get one. I was just hoping to get some feedback from somebody that has already shot with one. I don't want to mess up a new can. Thanks

I haven't seen the HKparts.net 3 lug adapters, but if you need a TROS one, send me an email--my shop carries them.

Awesome I'll shoot you a message. I'll try this one but honestly from looking at it I would be afraid to step on it. it looks like it would bend from my own weight. I could be totally wrong but I'll give it a try that way anyone in the future that has a question on it can find out.

March 16, 2016, 04:59 PM

g8rbreath

I have the hkparts 3 lug on my MPX 4.5" cut barrel. Ran 2 20rd mags thru my Tirant 45S super and subsonic last weekend with no problems at all.

March 17, 2016, 09:05 AM

SuperPollito

FYI (and this may depend on examiner) but my Form 1 was rejected because I listed the item as Sig MPX-P rather than Sig MPX.

March 17, 2016, 11:14 AM

SuperPollito

quote:
Originally posted by dwd1985:
quote:
Originally posted by SuperPollito:
FYI (and this may depend on examiner) but my Form 1 was rejected because I listed the item as Sig MPX-P rather than Sig MPX.

Yup, I had the same thing happen. Re-submit with just "MPX", then call your examiner with your old and new case numbers. They will expedite the
process, and it should only take an extra 4 or 5 days.

That's what I ended up doing as well. Only took 3 hours or so but we got it worked out. After redoing the paperwork, I believe the MPX-P was an option in their dropdown menu, i.e., not something I personally put in. But at any rate, all is well and my lovely telescoping stock can now be mounted.

March 17, 2016, 11:18 AM

g8rbreath

Same thing here, rejected today because I had Model as "MPX-P-9" which I chose from the drop down menu using eForms. A note on my disapproved form from the examiner said to change it to "Sig MPX" which looked like it was the only MPX option on eForms (they must have gotten rid of all the other variants). I submitted the new corrected Form 1 within 15 minutes and emailed the ATF Examiner to let her know. My new form was approved within half an hour. Stoked!

March 17, 2016, 11:48 AM

scubacuba

So I'm mulling over the purchase of a MPX. Is the 4.5" barrel even an option now as an afterthought? I've been perusing the net this morning but have yet to even find the barrel/handguard setup for sale anywhere. From what I've found, the MPX-K setup was/is only available for LE/GOVT. If the barrel is a purchasable retrofit, is/was a non-VFG handguard ever an option. I'm not (at this time) considering the NFA route. Any help? Thanks in advance.

March 17, 2016, 11:50 AM

creslin

4.5" barrel is not yet found in the wild.
to my knowledge the shipping estimate for them is "soon"
based on past experience... I'd anticipate maybe June timeframe for when we start seeing these things