New Sig Sauer MCX SPEAR LT in 5.56 nato

[Burdy]

Sig also tends to lock you into proprietary parts, again genius marketing. MPX's and MCX's you can't use standard AR triggers, the MPX bolt speed is so violent it destroys triggers, and the MCX needs it's own version as well. The MPX is so hard on triggers Gieselle tried for 2 years to make a trigger durable enough, after 2 years their only solution was to change recoil springs with the trigger to 30-55% stronger than stock. Another example of a gun Sig completely screwed up the recoil system on (P320 X-fives and P210's had issues here as well). Sure this new version addresses that, finally, but at Sig's prices, anyone with a MCX that wants to do the bolt upgrade is going to drop $800 doing it. Many of their handguns with optics cuts are locked into their optics pattern only. Almost everyone else either uses a plate system or their slides are setup for multiple options.

Not sure I understand/agree here. Owned a MPX and Rattler for several years running ATC AR Gold Triggers in both (AR-10 in MPX and AR-15 in Rattler) with no issue. The MCX doesnt tear up triggers. The reason they didn't work with standard triggers is because Sig installed the firing pin safety latch for the slam fire "issue." It had nothing to do with triggers.

In fact I actually have a Sig factory "G" marked firing pin safety latch that allows you to run Geissele and other mil-spec triggers in your Virtus. That's from Sig. I am running the Triggertech right now that works with the standard "S" marked latch. If you want to unlock ANY trigger it looks like you should just be able to replace the latch on the bolt with the Gen 3 version not the whole bolt itself. Some people just remove it all together and run whatever they want, although obviously Sig does not recommend that...but it wasn't there to begin with.

As for my Gen 2 MPX, it was suppressed from day 1 and cut from 8" to 4" and was an absolutely sewing machine. I know some had their issues but it never showed up on mine and it ate everything except speer gold dot g2. I loved the gun, just decided that I could do everything with a .300blk I could with a 9mm (and more) and I wanted mag pouch compatibility.

 

[GUNNER10]

Very true, but from what I've seen Sig quality and reliability of various MCX's isn't at the level of any of those other options. Perhaps this third generation will get them there.

I think that may have been the case with some 1st and 2nd generation examples but over the past couple years, they have started gaining traction down range, which would tend to indicate that the MCX has been evaluated against their peers by a number of organizations and found to be viable. you seen some US dudes running around with them in Syria, you have Ukrainian SF dudes running around with them, you have also have them showing up in smaller quantities in a number of NATO countries. I think this all points that Sig is on the right path with the MCX.

I would guess that if you could pull the latest test data against of the MCX and compare it to other rifles that are used in various service contracts. I would say that its actually probably pretty close.

I also think that one should really compare modern AR18's against AR18's to really access how good a particular weapon rather than comparing it against the AR15 which has benefited tremendously from having billions of dollars in R&D thrown at since the GWOT kicked off 20 years ago.

How is MCX compared to the Scar, Bren 2, ARX, BRN180, HK G36 and B&T APC? With the exception of the APC, I would assume that it compares quite favorable to most of these.

Interestingly enough, regardless of what is chosen as the next service rifle, there is a fairly good chance that it will have drawn its lineage from Stoner.

 

[Vynz]

As a chronic Sig purchaser and complainer I’ve experienced most of the complaints here. However I have to disagree with a few as well, namely Sig creating multiple incompatible versions were key features or corrections of real problems are spread over different generations to milk money from customers.

I had a couple Gen 1 MCX with both the 300Blk and 556 barrels. I also did the free BCG assembly upgrade to both when Sig announced it. When the Virtus came out I changed the barrel and bolt on one of them to the tapered bolt/heavier barrel just to see if was really better ($500 per cartridge). At the time my MCX were ~2MOA rifles. I found the Virtus barrel accuracy better than the Gen 1 barrels (~1.5MOA) but not enough to justify the 1-pound weight increase so I didn’t convert both. I did eventually buy a couple of Virtus Uppers as I wanted more rifles and the Gen 1 MCX was long discontinued. I paired the uppers with ambi AR-15 lowers as the MCX lower didn’t have ambi bolt control until now those uppers were about $1200 and caliber-x kits were still about $500 each. Having all the versions I compared them. The Virtus to the Gen 1 with Virtus bolt/barrel showed only the only cosmetic differences performing the same. The Virtus vs Gen 1 with only the recall upgrade BCG had better accuracy but at a heavier overall weight.

The past 3-ish versions of the MCX have not had any real upgrades that were not backwards compatible: MCX Gen 1 with the self adjusting gas system could have its barrels changed to the non-self adjusting versions; the MCX Gen 1.5 BCG with firing pin block was compatible with Gen 1 MCXs. When the Virtus came out the tapered bolts and heavier barrels were also backward compatible. In fact the only non-compatible difference the Virtus brought was heavier handguards which still didn’t hold zero well - this was where most of the “its not backward compatible“ complaining came from. In retrospect getting everyone’s panties all bunched up over not being able to go from the non-zero holding Gen 1 and Gen 1.5 handguards to the non-zero holding Virtus handguards seems ridiculous.

Now there is the Spear. Once again the major/real changes including: the lighter barrel, and AR-15 trigger compatible BCG changes are compatible with all the prior MCX versions. Like before, the hand guard still isn’t backwards compatible but time will tell if this new one actually holds zero or not. The screw anchors to the upper do basically nothing if the hand guard itself isn’t rigid so I remain skeptical it will be something to cry over.

When it comes to the MCX there has not been an upgrade, and I own every version, in any generation where an owner had to buy a new shiny part or the new MCX version due to a real performance deficit. Its all Sig marketing and the narcissism of needing to be in-season for those Instagram-likes but rather than admit how we are all manipulated by wanting the latest and greatest lets just complain about Sig and pretend the prior MCX versions were bad and left without any support or upgrade path.

 

[Burdy]

As a chronic Sig purchaser and complainer I’ve experienced most of the complaints here. However I have to disagree with a few as well, namely Sig creating multiple incompatible versions were key features or corrections of real problems are spread over different generations to milk money from customers.

I had a couple Gen 1 MCX with both the 300Blk and 556 barrels. I also did the free BCG assembly upgrade to both when Sig announced it. When the Virtus came out I changed the barrel and bolt on one of them to the tapered bolt/heavier barrel just to see if was really better ($500 per cartridge). At the time my MCX were ~2MOA rifles. I found the Virtus barrel accuracy better than the Gen 1 barrels (~1.5MOA) but not enough to justify the 1-pound weight increase so I didn’t convert both. I did eventually buy a couple of Virtus Uppers as I wanted more rifles and the Gen 1 MCX was long discontinued. I paired the uppers with ambi AR-15 lowers as the MCX lower didn’t have ambi bolt control until now those uppers were about $1200 and caliber-x kits were still about $500 each. Having all the versions I compared them. The Virtus to the Gen 1 with Virtus bolt/barrel showed only the only cosmetic differences performing the same. The Virtus vs Gen 1 with only the recall upgrade BCG had better accuracy but at a heavier overall weight.

The past 3-ish versions of the MCX have not had any real upgrades that were not backwards compatible: MCX Gen 1 with the self adjusting gas system could have its barrels changed to the non-self adjusting versions; the MCX Gen 1.5 BCG with firing pin block was compatible with Gen 1 MCXs. When the Virtus came out the tapered bolts and heavier barrels were also backward compatible. In fact the only non-compatible difference the Virtus brought was heavier handguards which still didn’t hold zero well - this was where most of the “its not backward compatible“ complaining came from. In retrospect getting everyone’s panties all bunched up over not being able to go from the non-zero holding Gen 1 and Gen 1.5 handguards to the non-zero holding Virtus handguards seems ridiculous.

Now there is the Spear. Once again the major/real changes including: the lighter barrel, and AR-15 trigger compatible BCG changes are compatible with all the prior MCX versions. Like before, the hand guard still isn’t backwards compatible but time will tell if this new one actually holds zero or not. The screw anchors to the upper do basically nothing if the hand guard itself isn’t rigid so I remain skeptical it will be something to cry over.

When it comes to the MCX there has not been an upgrade, and I own every version, in any generation where an owner had to buy a new shiny part or the new MCX version due to a real performance deficit. Its all Sig marketing and the narcissism of needing to be in-season for those Instagram-likes but rather than admit how we are all manipulated by wanting the latest and greatest lets just complain about Sig and pretend the prior MCX versions were bad and left without any support or upgrade path.

I know you know this but just so there is no confusion when you speak of the handguard holding zero, you are not talking about the barrel poi/poa but handguard mounted lasers.

 

[lord of war619]

Well the Spear Lt just made my once Rare FDE Virtus with anodized Surge handguard and tan anodize Kate Moss devalue since the whole thing is anodize now

 

[Glassaholic]

My KAC 11.5 with the new chrome bolt is being delivered tomorrow but I must admit I love piston rifles for suppressor work, the SPEAR LT 11.5 has my interest. I know the Knights is mid-range capable with Mk262, will be curious to see how capable the Spear is from 3-600 with Mk262...

 

[Ape_Factory]

Just seems like you're loosing a lot of velocity with a 5.56 round and an 11.5" barrel. Why not just do 300BO? Have to admit, I just cleaned my DI 300BO while swapping back to an 8.5" barrel and was appalled at just how dirty it was, suppressed, after 400 rounds with a flow-through suppressor. I mean it was ugly. Has me considering a piston for both the 5.56 and 300BO.

I'm at the very least intrigued but have to wonder where the .277 Fury went.

 

[Glassaholic]

Just seems like you're loosing a lot of velocity with a 5.56 round and an 11.5" barrel. Why not just do 300BO? Have to admit, I just cleaned my DI 300BO while swapping back to an 8.5" barrel and was appalled at just how dirty it was, suppressed, after 400 rounds with a flow-through suppressor. I mean it was ugly. Has me considering a piston for both the 5.56 and 300BO.

I'm at the very least intrigued but have to wonder where the .277 Fury went.

Don't discount the 11.5 too much, a 300BO could not do this (and I love my 300BLK)

 

[Ape_Factory]

Glad you posted that video, hadn't seen it before. Debating going with a shorter barrel on my 5.56 setup (or just getting a Spear LT) and while you can certainly ring steel with it, realistically, how much energy are we looking at on target though? I'll run a dedicated 5.56 can and looking at barrels in between the 12.5" and 14.5" range.

I've shot subs out to 300 with my 300 blackout and a 10.5" barrel. I read a book in between the shot and the ding, LOL.

 

[BG94591]

I got the 7.62 version a couple days ago. Nice rifle, shoots good, only tried brown bear 196 gr subs so far.

 

[Glassaholic]

Glad you posted that video, hadn't seen it before. Debating going with a shorter barrel on my 5.56 setup (or just getting a Spear LT) and while you can certainly ring steel with it, realistically, how much energy are we looking at on target though?

Not much, I'd imagine, but any less lethal than a 16" I'm not too sure, some camps have said you're not losing much between 16 and 11.5 but how that actually affects

I'll run a dedicated 5.56 can and looking at barrels in between the 12.5" and 14.5" range.

I've shot subs out to 300 with my 300 blackout and a 10.5" barrel. I read a book in between the shot and the ding, LOL.

Me too, beyond 300 yards and we're needing artillery ballistics

 

[WindstormSCR]

I got the 7.62 version a couple days ago. Nice rifle, shoots good, only tried brown bear 196 gr subs so far

I'm curious what company they're sourcing magazines from, or if they're making a design in house. Any markings? also curious for a pic of the bolt face, since I'd like to know how they handled the usual extractor issues x39 ARs are prone to.

 

[rimfirecity]

Super cool to finally see one of these

 

[BG94591]

I'm curious what company they're sourcing magazines from, or if they're making a design in house. Any markings? also curious for a pic of the bolt face, since I'd like to know how they handled the usual extractor issues x39 ARs are prone to.

 

[TonyTheTiger]

Don't discount the 11.5 too much, a 300BO could not do this (and I love my 300BLK)

I love stretching the little guys beyond what is commonly thought possible. But I have no experience with 300BO at longer ranges. Where does it hit the invisible wall?

 

[WindstormSCR]

pic

Classic duramags then. not the worst choice, but I was hoping sig would put some effort into making some nice steel mags with perhaps a slightly better follower design than the current ASC/Duramag designs.

kind of a shame e-lander doesn't do 25 or 30rd steel 7.62x39 AR mags

 

[Ape_Factory]

I love stretching the little guys beyond what is commonly thought possible. But I have no experience with 300BO at longer ranges. Where does it hit the invisible wall?

 

[GUNNER10]

I got the 7.62 version a couple days ago. Nice rifle, shoots good, only tried brown bear 196 gr subs so far. View attachment 7982096

Neat.

So it runs off of subs.... Interesting. Could definitely see a short 7.62X39 set up with a spare 14.5 556 barrel.

 

[TonyTheTiger]

Not sure if I would've posted that second video if I was him. Not much to see.
When I win the lottery I'm gonna do stupid stuff loke build a 24" 300BO just to lob some bullets way out yonder. I'll post a video when that probably never happens.

 

[lord of war619]

love my virtus but had to have the 7.62x39 sandman S clearance and I'm golden

 

[JLP83]

Anyone seeing these pop up in stock anywhere besides gunbroker?

 

[Burdy]

When someone nails down the BCG and/or safety latch part number, please let us know.

 

[Burdy]

love my virtus but had to have the 7.62x39 sandman S clearance and I'm golden

How is the 762x39 working out? Also, I know it lost some weight compared to the Virtus, but where was that weight loss? If there is anything I don't like about my 6.75" Virtus, it is how front heavy it is. I prefer weight on my AR's to be more rearward balanced.

 

[JKap23]

Anyone seeing these pop up in stock anywhere besides gunbroker?

They have popped up in multiple stores. Subscribe to in stock notifications and act quick. Look on gundeals. 7.62 pistol variant in stock at 2 places.

 

[LilGucci]

If I ever get the chance to buy a complete rifle, it's a toss-up for me between this, the FN SCAR, and the 556 options from LWRC and LMT. I honestly don't know which one is the best but my heart pulls me towards the Sig.

 

[mrtoyz]

If I ever get the chance to buy a complete rifle, it's a toss-up for me between this, the FN SCAR, and the 556 options from LWRC and LMT. I honestly don't know which one is the best but my heart pulls me towards the Sig.

I’ve seen you use the word “best” a few times. Best is so different for each person. Ford v Chevy.
IMO best is what fits your individual needs and visual appeal. Let’s face it looks matter… this is a hobby it’s not a work tool for most of us.
You’ve tapped on most of the high end brands now just go where your mood tells you. It’s all good.
I do agree something about the Sig floats my boat.

 

[LilGucci]

I’ve seen you use the word “best” a few times. Best is so different for each person. Ford v Chevy.
IMO best is what fits your individual needs and visual appeal. Let’s face it looks matter… this is a hobby it’s not a work tool for most of us.
You’ve tapped on most of the high end brands now just go where your mood tells you. It’s all good.
I do agree something about the Sig floats my boat.

Oh okay that's good to know. I've only heard of half of these brands and makes from visiting these forums so I don't know how they really compare. I know the Sig from Youtube videos. The Scar is sentimental, I've always wanted one from playing video games, but feel that they are overpriced despite being great guns. I already have an LMT AR-10 that I'm planning to build out in 2024, so that gives me exposure to LMT. I don't know too much about LWRC other than they've had some military contracts. I've always wanted to have one gun that has passed military trials and will be in military service, so that excites me about the Sig, plus I think it looks really cool despite having proprietary parts that are not standardized like an AR-15. I can only own one, and that's if I find one at a decent price here in Oregon. I'll do more research on all 4.

 

[mrtoyz]

If you’re on the clock because you live in OR just get what you can now.
You can find Scar’s on AR15.com equipment exchange fairly often.
LWRC’s should be fairly available. Historically they haven’t been super popular but IMO they’re good equipment.
KAC is great but you’ll pay out the ass right now.
LMT MWS is staring to be more available. Some great ideas on the MWS page here in the Hide. I just posted a build I did that I’m super happy with.
LMT 556 stuff is around as well and fun to build.

 

[GUNNER10]

Oh okay that's good to know. I've only heard of half of these brands and makes from visiting these forums so I don't know how they really compare. I know the Sig from Youtube videos. The Scar is sentimental, I've always wanted one from playing video games, but feel that they are overpriced despite being great guns. I already have an LMT AR-10 that I'm planning to build out in 2024, so that gives me exposure to LMT. I don't know too much about LWRC other than they've had some military contracts. I've always wanted to have one gun that has passed military trials and will be in military service, so that excites me about the Sig, plus I think it looks really cool despite having proprietary parts that are not standardized like an AR-15. I can only own one, and that's if I find one at a decent price here in Oregon. I'll do more research on all 4.

As others have mentioned, the stuff that you are looking at is all pretty high end stuff and you really can't go wrong. Most of these guns have the same pedigree, and have been refined with data they acquired from various US and Nato Defense testing. There is no best, but certain guns make a little more sense for certain applications


Honestly, if you fan of the scar from using it in video games, go for it. Don't get wrapped up in overthinking proprietary parts, most of these guns will last a lifetime with a few spings and a spare extractor.

Of the stuff you mentioned,
Sig seems like its the best attempt at a modern AR18, The large frame spear in .277 fury, feels like a meme rifle that I sort of want.
FN, makes a solid rifle and while my Scar 17 really didnt do anything for me, I am kind of digging the MK20 with a folder and cut back 6.5cm
LMT, Love LMT, Incredibly flexible and you can really set them out to suit your preference,
KAC, Love KAC, Especially their large frames that have a direct lineage to Stoner.

What ever you choose, i would just get out there and start putting down range and enjoy it.

 

[LilGucci]

As others have mentioned, the stuff that you are looking at is all pretty high end stuff and you really can't go wrong. Most of these guns have the same pedigree, and have been refined with data they acquired from various US and Nato Defense testing. There is no best, but certain guns make a little more sense for certain applications


Honestly, if you fan of the scar from using it in video games, go for it. Don't get wrapped up in overthinking proprietary parts, most of these guns will last a lifetime with a few spings and a spare extractor.

Of the stuff you mentioned,
Sig seems like its the best attempt at a modern AR18, The large frame spear in .277 fury, feels like a meme rifle that I sort of want.
FN, makes a solid rifle and while my Scar 17 really didnt do anything for me, I am kind of digging the MK20 with a folder and cut back 6.5cm
LMT, Love LMT, Incredibly flexible and you can really set them out to suit your preference,
KAC, Love KAC, Especially their large frames that have a direct lineage to Stoner.

What ever you choose, i would just get out there and start putting down range and enjoy it.

I think I'll go with the sig then, that's where my heart is at and it seems like its at a good price. The FN is a close second but I can only have one. Would love the KAC but I want something more AR-18-ish which is why I like the Sig and FN (and B&T APC308 and CZBren 2 308) and the KAC is too expensive haha.