All I want for Christmas is for Cabela's to start selling the LT so I can cash in all my gift cards and Cabela's credit card points that have been accumulating.

Can someone who has a SPEAR LT advise if a true 1.50" diameter suppressor will fit in the handguard? I know the position of the barrel is closer to the bottom of the handguard, however it seems a 1.5" can may fit. Hard to tell from videos

While not scientific, the base of this Ecco Five by Five uses a standard Hub adapter. I believe the diameter is damn near 1.5" or even a little less. It looks like it would not fit under the handguard.

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Did you have that barrel cut down?

Well I embraced the dark side! I have always liked the MCX/MPX line but never really wanted to spend the money on one. I ran across a Sig MCX Spear LT yesterday after my GD inspired trip to Green Top in Richmond Virginia. Could not get this thing out of my mind. Its a 16” with minimalist stock. I have plenty of SBR’s here and overall I love the feel of this thing.

My new Favorite is the MCX, the 10.5 Jakl SBR, and my Zastava Zpap 92 SBR with the Parker hill machine katemoss stock. Filed the paperwork for the Rebate yesterday, so when that comes back I will probably buy the folding collapsible low profile stock.  Threw a scope on it for now, waiting for my Sig Tango MSR SFP 1-10 to come in.  Ordered a rearden FHD for it since I already have a mount for the rifle cans since building the 8.6blk. Gave the SO a 5.7 Rock for Christmas, she loves it.

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Merry Christmas ARFCOM! Hoping everyone has a great day and gets to enjoy time with the Family.

No, sir. It's OEM 11.5 barrel. I am running an Ecco 1/2 x 28 direct thread to Sig Taper hub adapter. Perhaps that's why it looks closer to the rail than other setups.

Hub 1/2 x 28 to Sig Taper - Ecco Machine

Thanks! That Sig taper direct thread adapter is clean!

So figured I would let everyone know that my Muzzle device came off pretty easy. I ended up soaking it muzzle down for 30 minutes in warm water. I then clamped it in my gun vice with the foam jaws. Used the 19mm socket and a 30 inch breaker bar. I started to put force on it and it did not feel like it was going to go. Put some downward pressure and light tap on the breaker bar with a rubber mallet and it came right off. The jolting force and water worked well. This thing had Rockset oozing out if the seam between the barrel and flash hider, they applied way too much rockset in my opinion. Rearden 3 prong is on and test fire with the can has been accomplished.

Betting a small electric impact and soaking would make short work of it.

So I ordered the 11.5 conversion upper from Sig.  Just got the shipping notification.  I'm not sure what stock would be best to throw on.  I don't want to do an AR stock.  The standard collapsible folder would probably be the most versatile, but I like the look of the minimalist stocks.  I realize there 2 styles, a standard and mini, but then they offer each at 2 different price points.  One is $199 and the other $249.  What's the difference?  

Minimalist Stock $199

Minimalist Stock $249

Its the folding button on the stock. The old style does not have a locking button. I have the parker machine version of the Kate Moss on my ZPAP with the Sig adapter that does not lock. The locking button version is on my MCX Spear LT. i like both of the minimalist stocks but between the 2 the locking button is nice. I believe the spring pressure is reduced since the button locks it open. So the stock is easier to fold on the locking button version. The old version can be a pain to fold until you get use to it.

ETA: Beat like a rented mule! Yea it would come down to personal preference on either. Lock up feels about the same on both. For a hard use rifle the locking button for me gives me peace of mind. But the reality is the stock will deploy just as fast on either, since you will not be folding the stock until the threat is over.

Thanks guys.  How is the collaspible folder?  I presume this doesn't have the locking hinge given the price?  Is there any slop between the arm and the stock?  

Collaspible folding stock





How is the Kate Moss vesus the standard?

Telefold is the gold standard, as far as I'm concerned.  I'm not worried about the locking hinge.  It's super stable.

It’s probably the best one to start with.   It’s not like it’s that hard to change them around.

The hinge mechanism is amazing.  It's supremely solid and i don't think it will ever develop slop.  It's that well made.

There is some wiggle between the stock body and the collapsible extension but it's not so loose that it prevents getting a stable mount on the gun.

The biggest issue with this stock is how narrow it is.  I can make it work but it's not the most readily indexable rifle stock out there.  It's also a tad bit short for ME. (6'0 213 lbs).

I like them both. I have a Holosun AMES on the Zpap and figured the cheek riser would be better for the height of the RDS on the AK platform. The quality of the Parker Mountain is really good, right up there with the sig Minimalist. Just need to find a cheek piece for it at some point.

Lol.   I was just going back and rereading.   This is apparently fundamental as it says it right there in the title.  One is locking and the other isn’t.   I feel stupid.

Concur, the hinge is pretty good, even the non-locking one. No wiggle whatsoever.

I really didn't care for the I-beam stock, little too much slop and I tended to run it fully extended, so it's a fairly short stock, oriented towards folks wearing armor. It just wasn't as comfortable as a SOPMOD, either, which I ended up putting on one of the folding buffer tube adapters; two pieces of tape worked to shim the stock so it no longer rattled. Not very compact when folded, but that's the tradeoff for a better cheek weld.

The kate moss wasn't half bad for length/height, it was rock solid, folded nice and flat, much better than the I-beam. Problem was that it was an all aluminum stock, so the cheek weld was less than comfortable. Bit of camo tape kept it from freezing my face in the cold, but it was still fairly thin.

The newer minimalist plus stocks have a steel QD cup and can take their cheek riser, but need a little thought to solidify the riser mount, and they're a bit shorter in length/height. I can deal with the shorter LOP, but the toe height usually annoys me into going back to a SOPMOD.

Ordered the telefolder.  My 11.5 conversion kit should be here tomorrow.  Thinking I'm going to forego trying to change out the muzzle device just to put on my really old FA556-212 and get the process rolling on a SLX suppressor instead.  Will probably go with a 762 instead of a 556 though.

It works and locks when folded

Mine had rockset oozing out of it. Hot water from the tap and dropped it muzzle first in a cup. Let it soak for 30 minutes and clamped in my foam vice pads. Used a breaker bar and 19mm deep socket and gave it a solid tap with a rubber mallet and it broke free just fine. I think with the rockset it may help to remove it when it still has moisture in it.

I did remove the rail when I did it.  Just used my Real Avid Master Gun Vice and worked like a charm.

I end up sending my 11.5 inch barrel to Sig to get the mount removed.  I tried to remove it twice with propane torch.  That thing wouldn't even move, barrel was flexing like hell.  Sent it Tuesday and had back to my surprise on Sunday.

My SBR approval arrived mid week, after 11 days.  Not bad.

How did you clamp it?

Keep in mind rockset does not soften with heat unlike loktite. Water should be used to soften rockset. So hitting it with a torch will not do much, that is why it is used with suppressors.

I end up removing the barrel and clamped by the gas block.

Those of you who own one........is the Spear worth the coin?

Jeez.  I hope your upper receiver is okay.

So upper showed up today.   The picatinny section on the stock adopter was a little scuffed up,  but it’s just cosmetic  and will be covered up by the stock, which should be here Saturday.   The built in qd socket is a little lose.  It retains the swivels but allows them to spin.  

Was this supposed to come with a manual?  May need to call Sig tomorrow.

For me yes it was. I really love mine and it has quickly become my primary. I like it so much I want a spear in 308 or 6.5cm now as well. I guess it is personal preference here. Mine is a 16” with the minimalist stock. The feel in the hand is great, I was considering the collapsible folding stock for the LOP adjustment when running a plate carrier. But to my surprise the skinny nature of the stock allows it to catch my shoulder in the right spot but not throw the LOP off from the strap of the plate carrier. I have to runs some drills with it and see how it works in real conditions.

The recoil impulse is different, and the folding stock is great for keeping a compact system stowed and ready. Also piston is great for those of us that shoot suppressed. Its a quality build gun and you feel that as soon as you get your hands on it. I have enough AR’s and built a Jakl SBR last year. Really like the jakle as well but now I am kind of spoiled. I would love to have the spear LT in a 11.5, a 6.5” 300 blk and the full size. I would drop most of my AR’s with that combo.

To put things in perspective I am not a brand guy. Lots of good platforms out there and I do not shill for anyone, nor am I a brand snob. Only Sigs I own before this was some P229 that I picked up years ago. I have seen a lot of things SIG could have done better on, but this one I think they nailed it.

On a side note I had a rebate problem with them, so called customer service today. Took about 5 minutes to get through and they were extremely helpful.

I also had problem with the rebate.  Called them and I’m all good now.

I now have 2 spear lts.  Both in 556, one 11.5 SBR and 16 inch.  In my opinion, if you already have Virtus I would not bother getting LT.  It does not really bring anything exceptional to the platform.  I know, ambi bolt release, better HG etc.  To me those are just enhancements, not necessarily evolutionary changes.

My 11.5 inch 5.56 SBR is my primary training gun right now.

I absolutely adore the recoil impulse.  I have some very tuned AR15's and while the spear isn't as soft shooting as some of my AR's, it's got a very nice recoil impulse that is extremely predictable.  There is also nothing sharp about the recoil impulse which I really really like for my own personal shooting style.

The gun just gobbles up ammunition regardless of make.  I haven't seriously grouped the gun yet so I have no clue what it's really capable of.  I should put some glass on this thing and shoot some good ammo through it although I have very little doubt it will be at least 2 MOA with Speer Gold Dot which is all I really care about.

My only real gripe with the gun is its cost.  It's an expensive rifle.  It's not really "better" than a PSA AR15 that's assembled correctly.  It just does things differently and in a way that I appreciate.  IF the Spear LT was 1500 bucks I'd say confidently it's at the top of the heap for 5.56 rifles.  At 2400 bucks...meh.  It's good but only good for those of us that want to spend that much money.

If you've got the coin and you want a really nice 5.56 rifle, get the Spear LT.

Having owned one for a year now and shot it in several configurations:

Positives:

1) Overall I think it is a great design.  I think it is just right in terms of making what can/should be AR-compatible parts be AR compatible:  grips, trigger parts, extractor.
I really like some of the other design tweaks brought to the upper that should make it more durable than an AR:  The dual charging handle latches with the roll pin "edges", the steel cam pin path insert, and the improved modular forward assist.  I'm surprised no one has made an AR upper integrating this stuff, but I guess with an AR it is just cheaper to replace the upper if you ever get to that point.

2) I also really like the lower; in general it feels very high quality; sleek design with the dedicated/integrated pic rail on the back, good proprietary ambi bolt and mag catch.... steel integrated sling points if you like that... no complaints there.

3) Overall I think the operating mechanism is very robust.  I can see the bolt/carrier/recoil assembly lasting for a very long time.

On the downside:

1) To me the one glaring weakness in the design is the handguard lockup to the upper.  It is weak, bendy, and I don't believe it can be significantly improved without a total redesign, which would then not be anywhere close to backwards compatible with any existing MCX.  At least the upper rail is extended vs. an AR.  If you need anything to stay zeroed, that is where I would mount it.  At least it is modular so you can change it out to different lengths and profiles unlike with something monolithic, but it is not stable.

2) I guess this will be inherent to any piston design, but you are still starting with a lot of weight out front especially on a 16" rifle.  Once you start putting all the modern crap out on on the front of the handguard, there just isn't going to be much of a case to be made for the Spear LT vs a good 16" AR, based on weight alone.  The AR probably has the accuracy edge too.

Overall:  I think it makes a much better suppressed SBR than it does a 16" rifle.  Suppressed SBR is the configuration where the inherent benefits of the piston are maximized and the inherent drawbacks are minimized.  I like it in that config.

Overall worth the coin; that is going to be in the eye of the beholder and exactly how you define worth.  As a suppressed SBR it will likely shoot better for longer than a DI AR of similar config.  As a 16" rifle, probably not so much.

A $600 generic special will get the bullet to the target. Does a $2.4k Spear LT or a $4k Spear do it any better? I can't say the price justifies the performance, but it is what I grab first to go do rifle stuff. My handguard doesn't move but I don't play with lasers either.

If you have the scratch and want the rifle. Spend it and enjoy.

So with regards to the handguard, I do not have any flex in mine. Or I guess I should say any flex it springs back to the original position. Compared to all the rails on my other rifles, it flexes a lot less than both my Midwest Industries 15” hand guards. I am running an IR/Vis/IL on mine. I am actually running mine back on the extended upper rail. I mostly did that so I get a better view in my LPVO. I have not noticed any glare on the upper yet from the illuminator, but I just put the new one on and have to run some tests tomorrow.

I do like how easy the handguard is to remove.

So I just finished setting up initial iteration of my rifle.   I did the forward assist delete and noticed this…

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There’s a slot milled into the lower and 2 empty screw holes.   What’s going on here?

On a normal ar15 the tail of the carrier trips the auto sear. The MCX carrier doesn’t have a tail so the automatic guns have a sear trip that fits into that slot that the carrier hits which then trips the auto sear.  Sig does not install them into the semi auto uppers but the provision for the parts remains.

Got it.  Thank you.  

Data Point, finally got around to removing the muzzle device on MCX Spear LT SBR Upper.

Removed barrel, clamped in barrel vice, applied crescent wrench, with minimal - moderate effort came right off. No ooga-dooga required.

No soaking, heating, etc.

My SOT let me take possession of the upper, lower still sits at SOT in Form 4 purgatory. Since last Apr. ATF reports this is due to a NICS delay.

Funny enough, called the FBI NICS unit and they informed me that they do not execute the NICS checks for the ATF. So, somebody is full of shit. Anyone have any experience with that situation?

Just ordered an OCL Polonium K, may just keep the direct thread option and "permanently" ( small amount of Rocksett ) install the Polonium-K on the MCX.

Optic likely will be EXPS3-0. This rifle is intended to be the house gun. Seems that these are still the "best" choice for a dedicated CQB rifle.

Good luck with the Polonium, I found the Spear-LT to be extremely gassy despite being a piston system and the Polo's are high back pressure. I ended up swapping from the RC2 to the Flow556K which made a world of difference.

Is Huxwrx the way to go now? Seems like everyone is switching over to them.

I did the same. My 11.5" MCX SPEAR LT was to gassy so it got the Hux Flow 556k. Fixed the gassy problem and runs good on her.

Currently waiting on the SF RC3 cause I hate how the Flow attaches and has to be cleaned every 1500rnds.

I have a Griffin Dual Lok 5 in jail, interested to see how this thing does with a lower back pressure design that is not a flow through. My MCX was great with my Hybrid 46 with the 223 cap. Keep in mind the large Volume of the can and the over bore helps with backpressure. My MCX Spear LT is 16” though.

Anyone on here have a Legacy Midwest Industries 10.5 handguard they wanna sell? I figure someone upgraded and could help a guy struggling with a Keymod thick Boi rail.

The Flow556k is pretty great, I was a skeptic until I finally got my hands on one. The flash suppression under nods is pretty good on a 16", but questionble on the 11.5"

Another can to look at is the Velos LBP, every video I have seen of it testing flash has shown it nearly deletes it as well as the new RC3. SilencerCo also just announced they will have a 556K (5" in length) coming this year which if it performs half as well as the full size will be very good. Definitely on my list of purchases.

I'm in a similar boat as BlueShirtGuy, I don't have an RC3 in jail but I am patiently waiting the Mini3 release this spring. Surefire has never done me wrong, and I am excited to get my hands on one of those too.

Is anyone running their LT with a sig can?

I have a 11.5 556 LT and have run it with my SLH762itCQD, SLH300tiQD and my SLX556CQD lives on it (or my 10in legacy 556 MCX upper)

I snagged a CAT WB 718 for my spear LT. Should get a chance to play with it soon.

I run a SLX556C-QD on my 9" Spear LT.  It'll have a fun life while it lasts  

How would we feel about an M27 IAR Reimagined? Seeing as how the MCX is a distant cousin of the HK416

Later: Shorter 10in hand guard, maybe find a way to finagle a bayonet mount on the barrel

This just feels bigger than it needs to be.

I really want the SIG Cross Trax stock for my LT. I have a spare Spear locking hinge here just waiting for SIG to sell them as a spare part. I hope they just make them in Coyote too!

Hell, I'd probably run the Cross Trax stock on my Spear too! I prefer the skeletonized look over the tube and Magpul stock.