Sig originally sold us on the 8" barrel 9mm MPX with the promise of two conversion barrels in .357Sig and 40 S&W.

What happened to those two conversion barrels?

DOA. as is true of many of sig's promises on this gun and many others. Your just figuring this out now?

Manners

So, in other words, they were never released then?

Just an opinion, but to answer the title question...

The new CZ Scorpion is what happened to the MPX.

Love it or hate it, it is a comparable weapon from a quality manufacturer, with tons of accessories and options. And it's half the price.

In reference to the barrel thing, that is an unfortunate side of Sig. Their marketing/advertising seems to run way out in front of their production.

Hmm...in hindsight I'd say that it's more than likely that The Pentagon and like minded potential (and actual) military and agency clients of the MPX got in the way. I'd guess that all subsequent resources and development direction was chosen with that market in mind. And just as with so many other military suppliers and contractors, the whims and desires of the civilian market was at the very least given a much lower priority, if not entirely cast aside. It's not like there's much call for 45AUTO as a battle caliber, after all.

The irony is that contract sales of the MPX hasn't exactly been lighting things afire. The Army bought a small contract batch (but B&T got the juicy one), as did a small handful of foreign agencies. And that's kind of it, at least on the military side. What and how many police department SWAT divisions chose the MPX over, say, the MP5/SP5 or the aforementioned B&T is anybody's guess. Though it wouldn't surprise me if it were a relatively small number.

To throw another thing in, the PCC competition market got big. There's not much demand for anything other than 16" 9mm in that market.

I guess I take the OP’s question differently than some of the answers here. I take the question was what happened to the caliber conversion kits that SiG promised when Gen 1 MPX came out, not what happened to the MPX in general. The MPX is still out there and doing just fine, even in the face of competitors like the CZ Scorpion. What killed the conversions was likely SiG realizing that both .40 and .357 SiG were waning in popularity and that the cost to them of getting the conversions to run plus the cost of the conversions to the public weren’t going to be worth the investment. They spent their resources on improving the Gen 1 to make the Gen 2 in 9mm instead of wasting money making caliber conversions that few would have ended up buying. Plus add in typical SiG shortsightedness and desire to move onto the next big thing.

When the MPX was announced, I was really excited. But Sig shoving the Gen1 out the door while saying Gen2 is a few weeks away was a huge WTF. Plus ignoring the caliber conversion kits that never happened, and the magazine issues between the two Gens, Sig never released any of the other accessories that were promised. A few, like folding stocks that can be used on the MCX were out there, but none of the other items.

I had a neighbor who was looking at an MPX. I told him to check the magazine price first. He bought the Scorpion instead. SIG should make a MPX that takes 320 magazines like B&T. The mags are still expensive, but if you already have them for your 320...

quote:

Originally posted by von Trakehnen:
I had a neighbor who was looking at an MPX. I told him to check the magazine price first. He bought the Scorpion instead.

This is another reason I grabbed a Scorpion. I bought a ten pack of Magpul 35rd mags for $12 a pop a few months back. MPX 35rd? Just under $50. Ouch.

quote:

Originally posted by P220 Smudge:

quote:

Originally posted by von Trakehnen:
I had a neighbor who was looking at an MPX. I told him to check the magazine price first. He bought the Scorpion instead.

This is another reason I grabbed a Scorpion. I bought a ten pack of Magpul 35rd mags for $12 a pop a few months back. MPX 35rd? Just under $50. Ouch.

Maybe for the original MPX Lancer mags, but now the factory mag is the Thril 35 round mag, which is in the mid $30 range. Still more than a dirt cheap Scorpion mag, but not bad.

I like my MPX Gen 2. Typical Sig "rolling changes" they now have a newer generation, Gen 3?

I don't believe the MPX has a "Gen 3". Just the MCX has "Gen 3" in the form of the LT. The MPX is relatively unchanged. New skus simply swapped the Lancer 30-rounders for the cheaper Thril 35 rounders, and then removed the brace from the Copperhead and K-variants to get ahead of the ATF Brace "redefining" point system.

However, the reduced cost mags and elimination of the brace did not result in a reduction of the price. In fact, the price has only increased, reducing value comparatively with the Turk MP5 clones and Scorpion prices hitting rock bottom. I believe they have been realigning the MPX in the boutique PCC market.

Sig seems to be chasing the novice competitive PCC market while keeping MPX prices under JP enterprise. I think this is a mistake as the big benefit to the MPX is the ability to fold or collapse the stock for compactness (SD purposes). JP models don't desire this, as they are designed for competition use and can stretch the recoil assembly closer to the shooter using their Silent Capture System and take full benefit of the Roller Lock system.

The MPX copperhead does have some changes as they phased out the 8” for the 4” with no threads to the 4” with threads. But probably not enough to call it a Gen 3 just a different model

Have a gen1 version, SBR'd with silencer. It's an excellent firearm

Have any firearm lines with "caliber change kits" every really worked, remember that was the idea of the P250, and P320, you could own one FCU and make it into anything you wanted, full size, compact, sub compact, different calibers

In reality the cost of the exchange kit, with mags and you were close to the cost of buying a new model.

Theoretically it's an interesting idea, but in reality not sure it ends up being successful...

I had the opportunity a couple of years ago to shoot full auto MPX and MP5s together with my CZ Scorpion at the same time.

The MP5 was clearly at another level for construction and build quality. The MPX was nice but even factoring in the cost of 922r parts, I didn't think it was worth the difference in cost between it and the CZ. And when you factor in magazine prices and all the aftermarket support for the CZ, I just don't see the MPX being a better choice.

Don't get me wrong, the MPX is a nice PCC, I just think there are better options out there.

I have an 8" Gen 2 and dumped a fair amount of coin into the rather expensive Gen 2 magazines, which Lancer made for SIG, modified a few of them with Taran base plates. Suffice to say I spent way too much on magazines/modifications.

Then SIG launched the THRIL 35 round magazines, way better pricing, that rather pissed me off.