I have a MCX Rattler GEN 2 I guess it is. It’s the Virtus model. I love it. The Spear LT is the latest and greatest. It is lighter, has a different profile barrel and has ambi bolt catch and release. They have great reviews. I don’t think they make a Canebrake in the Spear LT line. But I’m not sure of that. Oh it also uses the MLOK rail which is nice. If you can afford one I say go for the Spear LT. Either the Rattler LT or another 9” which ever you prefer.

 

The best feature of the LT is the ambi bolt release. The aftermarket ones don’t fit on the Virtus.

 

I've settled on an LT lower with a Rattler upper. I thoroughly enjoy subs so I don't need the 9" barrel it came with plus I'm fine with losing a bit of velocity with supers, so aside from a suppressor still in jail, this puppy is just about finished.

 

I've settled on an LT lower with a Rattler upper. I thoroughly enjoy subs so I don't need the 9" barrel it came with plus I'm fine with losing a bit of velocity with supers, so aside from a suppressor still in jail, this puppy is just about finished.
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I wonder if I should just slap a rattler upper on my current lower just to shorten it up and avoid the proprietary trigger necessity.

 

I held out on the MCX for the longest time because even though I'm right handed, I needed a full ambition lower. Am I glad I held out, I finally settled on a Spear-LT 11.5" SBR in 5.56 and I couldn't be happier. The slimmer hand guard profile I find extremely ergonomic and easy to mount any accessories. This really is the MCX system being refined as much as possible, it easily compares to and even exceeds some of the higher end AR brands like LWRC, DD, LMT, and others

 

In 5.56 they made a lot of improvements. Like relocating the gas block for example.

If you were into 5.56 I would say it's worth upgrading the whole gun to get the universal bolt carrier plus improved gas system plus Ambi lower.

Alternately you could get the new barrel and tapered lug bolt.

However if your a dedicated 300blk guy then there's nothing wrong with staying with what you've got now in my opinion.

 

I'm noodling now on which will be my first Sig in 300blk. I already have two MCXs in 5.56. With 300blk it's a tough decision. To me there are only two choices. Since I waited a few years until the LT was released to buy a 300Blk, to my mind there is only the Rattler LT 6.75" barrel in 300blk and the 9" LT. I won't buy a shorter barrel then 6.75" for reliability and utility reasons. And 9" is as long as I want to go for manuverability and concealment.

The Rattler; To me the short Rattler is a PDW only weapon, and I would really only shoot subs with it.
As a weapons system, it would have a dedicated can, a sling and grey man backpack bag. I would find the optimum reliable sub load and that's all it would eat. I cannot see myself running around in the woods, defending my property with a Rattler. PDWs are for very CQ self defense (IMHO, if you live in the city, the Rattler is still pretty short), and after I got a Rattler tuned I would keep it static and practice with getting holds right. I don't see the Rattler as very effective past 100 meters or so or taking precise shots without a lot of practice. In my head, I see the Rattler PDW lobbing huge chunks of lead quietly in a rainbow trajectory at short distances. Forget precise life-or-death shots at any real distance. Also, I think the rail is way too short for weapon lights and lasers currently on the market.

MCX LT 9"; The nine inch LT in 300blk, would be an all-around rifle for me. I would find (am looking) for a dedicated suppressor that would make subs QUIET, while also helping to quiet supers. The 9" rifle would have to run subs and supers with dead reliably. I feel that the slightly longer barrel is amenable to more utility, as velocities increase, and even a couple extra inches of rail makes things less crampted.

I think the LT 9" is a better rifle for running subs and supers interchangeably and reliably, and that would be a requirement for me. I want to have the choice of dropping my mag of Subs, putting in a magazine of Supers, and immediatly being able to do a lot more damage. Of course 7.62x39 is better at doing damage and that might be an alternative if you don't care about quiet.

Between the 300blk Rattler LT and 9" LT, the only difference really is a name and 2 inches of barrel. But 2 inches of barrel can make a difference in reliable operation, and translates into precious rail space too.

I'm a fanatic about reliability in my high end rifles. I don't want to put $2700 into the rifle, $1700 into the can and muzzle device, $1500 into optics, $350 into a light. And have a cool looking $6000 dollar polished turd.

The way I look at it, after testing ammo, If I ever have to clear a malfunction other than because I jammed a bunch of dirt into it, never lubed it, or got a bad magazine, I probably won't trust it. And I expect the rifle to run, even abused.

I think it might be a lot to expect a specialized weapon like a Rattler to take as much abuse as I want to dish out. So I think right now I'm planning to go with a slightly more flexible 300blk build, the LT with 9" barrel. That's if I can find the right suppressor to go with it, and get the sub/super interchangeability right.

And that's another thing, if I can find an effective short suppressor that, when paired with a 9" LT 300blk, allows for good sound and flash suppression. Then I'm just not losing a lot in the way of concealment, and maneuverability.

Anyway, I already have a couple MCX LT rifles/pistols in 5.56. I sent the 16" back to sig to see if they can keep the barrel from wobbling around (dissapointing!), but I recently got an 11.5" Sig Custom Works pistol that I love.

I ordered a SF RC3 last night for it.

Next project will probably be a MCX LT 9" barrel 300blk, with supressor, If I can reach the goals of the project.

My two current projects...
14.5 Geissele Super Duty, Night Force ATACR 1-8, Surefire RC2, great suppressor host, only had to change buffer from H2 to H3, no gas, and shoots very smooth. I was going to use the Sig MCX LT 5.56 16", but I'm not happy and sent it back to Sig for them to look at it. I may ditch the 16" MCX LT. We will see when it returns.

Sig MCX LT 11.5" 5.56 pistol, Sig Custom Works. Aimpoint T2 and Aimpoint 3X magnifier (I also have an EOTech 5x, makes it too difficult get to the CH) on Unity tall mounts for use with night vision. Waiting for SF RC3. I want to like the Sig trigger, I have a Geissele SSA-E and SSAE-X on my desk, but I'm trying to like the Sig trigger. tHE Sig charging handle they put on was WAY to narrow for this. I went to the Sig LT large latch which might be too big (There is a medium size available). Sig needs to step up to the plate and redesign their charging handles for better ergonomics. I wanted to stay with Sig because they have latch points on each side of the gun, only Sig CH uses both latches at the same time. I call Sig's charging handles, "the cruel charging handles", because they will tear your hands up, being too narrow and sharp edges. OTHERWISE, i love the 11.5" 5.56 MCX LT.

 

I'm noodling now on which will be my first Sig in 300blk. I already have two MCXs in 5.56. With 300blk it's a tough decision. To me there are only two choices. Since I waited a few years until the LT was released to buy a 300Blk, to my mind there is only the Rattler LT 6.75" barrel in 300blk and the 9" LT. I won't buy a shorter barrel then 6.75" for reliability and utility reasons. And 9" is as long as I want to go for manuverability and concealment.

The Rattler; To me the short Rattler is a PDW only weapon, and I would really only shoot subs with it.
As a weapons system, it would have a dedicated can, a sling and grey man backpack bag. I would find the optimum reliable sub load and that's all it would eat. I cannot see myself running around in the woods, defending my property with a Rattler. PDWs are for very CQ self defense (IMHO, if you live in the city, the Rattler is still pretty short), and after I got a Rattler tuned I would keep it static and practice with getting holds right. I don't see the Rattler as very effective past 100 meters or so or taking precise shots without a lot of practice. In my head, I see the Rattler PDW lobbing huge chunks of lead quietly in a rainbow trajectory at short distances. Forget precise life-or-death shots at any real distance. Also, I think the rail is way too short for weapon lights and lasers currently on the market.

MCX LT 9"; The nine inch LT in 300blk, would be an all-around rifle for me. I would find (am looking) for a dedicated suppressor that would make subs QUIET, while also helping to quiet supers. The 9" rifle would have to run subs and supers with dead reliably. I feel that the slightly longer barrel is amenable to more utility, as velocities increase, and even a couple extra inches of rail makes things less crampted.

I think the LT 9" is a better rifle for running subs and supers interchangeably and reliably, and that would be a requirement for me. I want to have the choice of dropping my mag of Subs, putting in a magazine of Supers, and immediatly being able to do a lot more damage. Of course 7.62x39 is better at doing damage and that might be an alternative if you don't care about quiet.

Between the 300blk Rattler LT and 9" LT, the only difference really is a name and 2 inches of barrel. But 2 inches of barrel can make a difference in reliable operation, and translates into precious rail space too.

I'm a fanatic about reliability in my high end rifles. I don't want to put $2700 into the rifle, $1700 into the can and muzzle device, $1500 into optics, $350 into a light. And have a cool looking $6000 dollar polished turd.

The way I look at it, after testing ammo, If I ever have to clear a malfunction other than because I jammed a bunch of dirt into it, never lubed it, or got a bad magazine, I probably won't trust it. And I expect the rifle to run, even abused.

I think it might be a lot to expect a specialized weapon like a Rattler to take as much abuse as I want to dish out. So I think right now I'm planning to go with a slightly more flexible 300blk build, the LT with 9" barrel. That's if I can find the right suppressor to go with it, and get the sub/super interchangeability right.

And that's another thing, if I can find an effective short suppressor that, when paired with a 9" LT 300blk, allows for good sound and flash suppression. Then I'm just not losing a lot in the way of concealment, and maneuverability.

Anyway, I already have a couple MCX LT rifles/pistols in 5.56. I sent the 16" back to sig to see if they can keep the barrel from wobbling around (dissapointing!), but I recently got an 11.5" Sig Custom Works pistol that I love.

I ordered a SF RC3 last night for it.

Next project will probably be a MCX LT 9" barrel 300blk, with supressor, If I can reach the goals of the project.

My two current projects...
14.5 Geissele Super Duty, Night Force ATACR 1-8, Surefire RC2, great suppressor host, only had to change buffer from H2 to H3, no gas, and shoots very smooth. I was going to use the Sig MCX LT 5.56 16", but I'm not happy and sent it back to Sig for them to look at it. I may ditch the 16" MCX LT. We will see when it returns.

Sig MCX LT 11.5" 5.56 pistol, Sig Custom Works. Aimpoint T2 and Aimpoint 3X magnifier (I also have an EOTech 5x, makes it too difficult get to the CH) on Unity tall mounts for use with night vision. Waiting for SF RC3. I want to like the Sig trigger, I have a Geissele SSA-E and SSAE-X on my desk, but I'm trying to like the Sig trigger. tHE Sig charging handle they put on was WAY to narrow for this. I went to the Sig LT large latch which might be too big (There is a medium size available). Sig needs to step up to the plate and redesign their charging handles for better ergonomics. I wanted to stay with Sig because they have latch points on each side of the gun, only Sig CH uses both latches at the same time. I call Sig's charging handles, "the cruel charging handles", because they will tear your hands up, being too narrow and sharp edges. OTHERWISE, i love the 11.5" 5.56 MCX LT.

View attachment 587129

A lot of good considerations here. I can say that my current MCX with the 9" barrel runs subs and supers flawlessly on the same "suppressed" or "-" setting with a SiCo Omega 300. That is a good point about barrel length and wanting the versatility the cartridge was designed for. Thanks for the thought process.

 

I run my 9" legacy with a Rex Silentium MG7K, which is a tad over 5" using a Dead Air direct thread hub mount which has the Sig taper on it so it never comes lose.

It's very quiet and compact. The can favors supers, there are a lot better cans for subs. But my priority was short with supers. So it's a good fit for me.

 

I have a MCX Rattler 5.5” with DA Nomad and it has run all subs perfectly on the “-“ setting. The few different supers I’ve ran were perfect too. No problems at all with this setup. I love it.

 

Solid pair you have there

 

I own both the spear LT 9” 300 blackout and the rattler Canebrake. Both are amazing and i haven’t had any issues with either one. That being said, I have a ton of leftover powder or filler from the rounds in the chamber with the canebrake. Not so in the spear lt with its 9” barrel

 

Man this whole time I was thinking a shorter barrel could be nice for stowing and what not but this thread has me thinking my 9" barrel is just where it's at. Especially for supers. This is why I asked haha!

 

One thing I'll mention that no one has brought up is barrel length, twist rate and muzzle velocity in relation to the type of projectiles you can run safely.

I own the 9" Spear LT and both it and the Rattler have a 1:5 twist barrel. With the 9", you can achieve velocities out of 110 grain or 120 grain projectiles that could cause jacket separation with bonded bullets. Not good if you're running a suppressor.

The shorter barrel of the Rattler keeps velocities in check so you can run any supersonic bullet you want. Not so with the LT and you'll want to run monolithic bullets only, nothing with a lead core.

I'd hand loaded a ton of supersonic rounds, both Hornady V-Max 110 grain and Speer 125 grain rounds prior to purchasing the Sig. I can't safely use those rounds in the LT. Luckily I had a ton of leftover parts after disassembling two DI rifles and built a short barrel 8" DI rifle back up so I could shoot cheap supers/jacketed/bonded bullets.

Monolithic cartridges like the Barnes 110 grain and 120 grain are not cheap. Something to consider.

I purchased the Sig as neither of my two home-built DI rifles would run the Hornady Sub-X 190 grain rounds reliably, factory or hand loads. The Sig just eats them up.

In Mac's video, he's using a subsonic round with a projectile designed for supersonic velocities. It's really not a surprise that the lower velocities in the 5.5" barrel cause tumble and thus more destruction. I think the test would have been better had he used a round that was designed to expand at subsonic speeds.

Gratuitous photos, Sig first, followed by my home brew "truck gun" in 300 blackout.



She may be lighter but she's still chunky. Add another 12oz for the suppressor. It's well balanced though and the mass is fairly centralized.


The DI gun with an 8" barrel and no accessories is around 4.5 pounds, not much more with BUIS and RDO. The Sig with the stock folded is more compact. Still, this is a gun anyone could pick up and use effectively. I use a lightweight titanium BCG (RCA) and an Unrivaled dead blow buffer and there's not much recoil compared to the Sig which is a bit on the brutal side for what it is.


Ultimately it comes down to your intended use in your environment. I wouldn't put much weight on Mac's video TBH. If you're going for tumble, you could theoretically pick any long projectile and get them down to say 800-850fps out of the 9" barrel and get the same tumble effect. I'd rather run a bullet that'll expand at subsonic velocities then dial it in at 1050fps at 75 degrees Fahrenheit (inside your home temp). One mag with subs, one mag with monolithic supers, say Barnes Tac-TX, and you're GTG. If you need more, I suggest moving out of the neighborhood.

 

One thing I'll mention that no one has brought up is barrel length, twist rate and muzzle velocity in relation to the type of projectiles you can run safely.

I own the 9" Spear LT and both it and the Rattler have a 1:5 twist barrel. With the 9", you can achieve velocities out of 110 grain or 120 grain projectiles that could cause jacket separation with bonded bullets. Not good if you're running a suppressor.

The shorter barrel of the Rattler keeps velocities in check so you can run any supersonic bullet you want. Not so with the LT and you'll want to run monolithic bullets only, nothing with a lead core.

I'd hand loaded a ton of supersonic rounds, both Hornady V-Max 110 grain and Speer 125 grain rounds prior to purchasing the Sig. I can't safely use those rounds in the LT. Luckily I had a ton of leftover parts after disassembling two DI rifles and built a short barrel 8" DI rifle back up so I could shoot cheap supers/jacketed/bonded bullets.

Monolithic cartridges like the Barnes 110 grain and 120 grain are not cheap. Something to consider.

I purchased the Sig as neither of my two home-built DI rifles would run the Hornady Sub-X 190 grain rounds reliably, factory or hand loads. The Sig just eats them up.

In Mac's video, he's using a subsonic round with a projectile designed for supersonic velocities. It's really not a surprise that the lower velocities in the 5.5" barrel cause tumble and thus more destruction. I think the test would have been better had he used a round that was designed to expand at subsonic speeds.

Gratuitous photos, Sig first, followed by my home brew "truck gun" in 300 blackout.



She may be lighter but she's still chunky. Add another 12oz for the suppressor. It's well balanced though and the mass is fairly centralized.


The DI gun with an 8" barrel and no accessories is around 4.5 pounds, not much more with BUIS and RDO. The Sig with the stock folded is more compact. Still, this is a gun anyone could pick up and use effectively. I use a lightweight titanium BCG (RCA) and an Unrivaled dead blow buffer and there's not much recoil compared to the Sig which is a bit on the brutal side for what it is.


Ultimately it comes down to your intended use in your environment. I wouldn't put much weight on Mac's video TBH. If you're going for tumble, you could theoretically pick any long projectile and get them down to say 800-850fps out of the 9" barrel and get the same tumble effect. I'd rather run a bullet that'll expand at subsonic velocities then dial it in at 1050fps at 75 degrees Fahrenheit (inside your home temp). One mag with subs, one mag with monolithic supers, say Barnes Tac-TX, and you're GTG. If you need more, I suggest moving out of the neighborhood.

What's the breakdown of that stock?

 

LVAW clone. I just wish SIG would do a run of them similar to the SURG kits.

 

What makes the LVAW the “best”? I’m not arguing I just don’t know much about that model. What are some of the differences between it and the other models? I ve heard this several times now and would like to see one. Was this a model civilians could buy or only military sales?

 

In light of the video, can we just say the 300LK round of choice for Home Defense, should be a hollow point, if Sub Sonic?

 

I think I’m going to buy a Spear LT in 300blk and pick up a Dead Air Nomad ( 8 inch one) for my next rifle.