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Old 02-03-2018, 06:14 AM   #378
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Default SIG MCX LVAW 'Black Mamba' .300 Blackout

SIG MCX LVAW 'Black Mamba' .300 Blackout

The rumour is that a JSOC contract for a Low-Visibility Assault Weapon (LVAW) was won in April 2015, by the SIG MCX in .300 Blackout, dubbed the 'Black Mamba' for its ability to 'kill' the Honey Badger's chances at the same contract.

From uncomfirmed reports on the Internet, as well as Leigh Neville's Guns of Special Forces 2001-2015, CAG/1st SFOD-D were working with SIG Sauer in developing a weapon with very similar qualities as the Honey Badger that DEVGRU was working on with AAC.

The CAG/Delta test weapons were allegedly SIG uppers with a 6.75" barrel and either a 1:5 or 1:6 twist rate (sources differ, both may have been tested or the 1:5 could have been only tested with the shorter 5.5" barrel), attached to a lower from JSOC armouries, probably an M4A1 lower, but conceivably a unit purchase of another AR-15 type lower.

JSOC may or may not have received complete carbines from SIG Sauer later on in the testing proccess, with 'Guns of Special Forces 2001-2015' making specific references to SIG MCX weapons, mentioning one with a CQB 9" barrel (MCX SBR) and one with a 16" barrel (MCX Carbine). Due to the modularity of the MCX design, changing barrels would be easy to do by the individual operator, so it is possible that all three barrel lengths were available on the same weapon.

From what I can tell, it appears that the SOCOM tender for a new PDW, which sounds very much like what JSOC was seeking with its Low-Visibility Assault Weapon, will be met by SIG Sauer uppers designed to make M4A1 carbines into weapons very close to the SIG MCX.

Of course, Special Mission Units (SMU) under JSOC, like CAG/1st SFOD-D and DEVGRU, have not always been bound to use the same weapons as the larger SOCOM command and not only does JSOC have its own budget and logistics chain, the individual units have wide latitude for unit purchases of necessary equipment.

However, it must be considered unlikely that JSOC will bother to acquire similar capabilities from another source if SOCOM has indeed accepted the SIG MCX (or as good as), especially as the acquisition process here seems likely to have been driven by JSOC and to reflect their internal selection of the SIG MCX LVAW 'Black Mamba' in 2015.

That weapon was apparently chosen after a testing process which seems to have been an informal exchange of ideas and development with AAC and SIG Sauer between 2009-2011, and may have become formal, well, as formal as classified acquisition contests ever are, around the year 2012. The selection of the SIG MCX LVAW (or LVAW upper from SIG, perhaps) was made in April 2015, as noted above.

Now, when our campaign is set, in February 2017, a year before SOCOM reached its decision (a couple of days ago in real life), and almost two years after JSOC allegedly bought an unknown number of LVAWs from SIG Sauer, in an unknown final configuration, there could have been a range of configurations of the SIG MCX available to operators from DEVGRU's Black Squadron. It's not certain or even likely that all the weapons JSOC tested, or the one eventually adopted by JSOC in 2015, is identical in specs to the PDW upper adopted by SOCOM in 2018.

Unless I hear arguments or find evidence that this is implausible, I shall be assuming that the 6.75" barrels were available for at least two and probably more weapons that the operators could get their hands on.

Edit: CAG/Delta was using 6.75" barrel MCX LVAW in late 2016, so we'll call availability of that one confirmed. DEVGRU is rumoured to be less fond of the compact MCXs than CAG/Delta, but they were allegedly running some .300 Blackout carbine with a 12.5" barrel in 2016. Can't confirm whether they were MCXs with a special order for barrel length or a different weapon / upper receiver group for AR-15 type lowers acquired as a unit purchase. Also, there are rumours about the new version of the Honey Badger by Q being tested on an individual or unit level by DEVGRU, even after JSOC as a whole selected the SIG MCX.

I can't confirm whether the operators have complete rifles from SIG or are using M4A1 lowers with SOPMOD accessories and standard M4/CAR/RRA 6-positions stocks. The SIG MCX lower is not identical in function to the M4A1 lower and perhaps the most vital difference is that the MCX doesn't use the stock as part of the gas system/buffer tube. As a result, the MCX can mount a folding stock or a stock that is fully retractable, and the weapon would fire without the stock deployed. This allows a significant reduction in overall length (OAL), which makes the weapon much more concealable during covert insertion or low-profile bodyguard missions. So a SIG-made complete MCX LVAW carbine would have an advantage over a weapon constructed from existing JSOC lowers and only buying uppers from SIG Sauer.

Does anyone know whether some of the MCX LVAW carbines tested by CAG/ACE (1st SFOD-D/Delta) and the rest of JSOC between 2012-2015 were early production models of complete MCX weapons or whether they were all just assembled by unit armourers from existing parts and SIG MCX uppers?

Does anyone have a guess as to which they'd find plausible?

My personal guess, unless convinced otherwise, is going to be 'both'. It was a testing proccess, they tried several variations. But the test weapons might have been only a half dozen or a dozen, over the whole command.

What about the more numerous order of low-visibility carbines in .300 Blackout they bought as part of the LVAW contract between April 2015 and February 2017?

More expensive, but objectively slightly superior, complete weapons from SIG?

Or a more economical purchase of only SIG MCX uppers in .300 Blackout, because they have enough M4A1 lowers with shot-out barrels, even if they end up half a foot longer when folded for concealment?

The cheaper option would be cheaper by maybe $100 to $500 per unit, depending on how much of the SOPMOD Block II furniture they could re-use from their existing stocks. I don't know the per unit replacement price of an M4A1, let alone just the lower, but in the civilian world, similar lower receiver groups with stocks go for $150-$250. SIG probably sells theirs for more.

The rails and various other furniture adds to that, so the savings could be fairly substantial. On the other hand, existing rails and a lot of what they have in stocks as part of SOPMOD Block II kits can just as easily be mounted on complete SIG MCX carbines, if they are ordered without any extras that you already have.

The third option for the MCX configuration available to the SEALs watching over our PCs is if I assume that in our world, in early 2017, JSOC had already done what SOCOM is doing this week, with the ten PDW uppers they are buying (probably the first of several orders), and just bought SIG stock adapters, folding/telescoping stocks and skeletonised PDW stocks as parts with their ordered uppers, allowing them to still get some use out of their old M4A1 lowers, even if they are by now replacing most of the original parts.

That way, all the SIG MCX carbines used for testing could still be available from the JSOC armouries, but with the stock that operators are likely to have preferred in a weapon designed for concealment, regardless of how they originally arrived. This is actually quite plausible.

Sound suppression

The 'Black Mamba', as supplied to CAG/1st SFOD-D during testing, is allegedly 10 dBs quieter than the AAC Honey Badger model which was supplied to DEVGRU. That's another -1 Hearing, no matter what I give the Honey Badger. Of course, if I round favourably to the Honey Badger, I will also end up giving the 'Black Mamba' stats that are more favourable than the actual measured dBs, I imagine, possibly more favourable than any existing firearm other than slide-locked .22 LR pistols with the best suppressors in the world and some kind of hypothetical bolt-action carbine with small, low-powered subsonic rounds and a massive suppressor.

Once I have the stats for the AAC Honey Badger, working up the 'Black Mamba' stats ought to be a snap.
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Last edited by Icelander; 02-04-2018 at 09:15 AM.
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