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LaRue, Colt, KAC Battle Carbines Compared Part 1

Happy Thanksgiving all.

Today I am thankful that I got to try a few different rifles this morning.  I did side by side shooting of a Larue 7.62 Ultimate Upper rifle, Colt LE901-16SE, and a KAC SR25-EC.

It isn’t really fair to directly compare these as there are some major differences between them.  Sort of like comparing apples to apples to oranges.  But that never stopped me from being critical about things before.

This first comparison will be short.  I had these three rifles available to me so I decided I would start with 20 rounds each rapid fire with an Aimpoint T-1.  I would do some rapid engagements of a target at 10 yards, and do some double taps at 10 yards.  I ended up firing 32 rounds from the Larue due to functioning issues, and only 20 from the others.  Not exactly a comprehensive test, but a start.

From top to bottom, KAC, Larue, Colt.  20 round groups rapid fire off hand at 10 yards.  Mostly rapid pairs.

I shot the Colt LE901-16SE first.  When Colt release the 901, they first released the LE901-16S, which was a full railed model.  I believe they sold a few -18S with an 18 inch barrel.
After that, they release the -16SE.  They shaved a pound off the rifle by replacing the quad rail on the monolithic hand guard with a proprietary modular rail.  This model appears to have been discontinued and the newest model, the CM762 adds an ambi safety, longer MLOK hand guard, and an ambi charging handle.  The new model is also available in 6.5 Creedmoor with a 18 inch barrel.

The rifle is is stock configuration with a Aimpoint T-1 added to it for the comparison.  With the exemption of the lack of an ambi safety, I found the controls on this rifle to be the best.  The right side bolt release is easier to hit, the larger and lower left side mag release gives more leverage and is easier to use.

The list weight on the -16SE is 8.4 pounds.  When I shot it I found it tended to recoil straight up.  I felt that it was fast and easy to shoot, but my performance on paper was the worst with it.  Back when I the 901-16S side by side with the 901-16SE, I found that that 1 additional pound of weight made the fully railed 901-16S have much less felt recoil.

The Ultimate Upper is an economy large frame rifle kit from Larue Tactical.  You can purchase the upper kit in SR25 or DPMS pattern.  If you buy a kit you can buy a Larue lower for it.  This isn’t really a fair comparison to the others as I added a Surefire Warcomp to this rifle.  The Warcomp can drastically reduce recoil.  I think this gave the Larue the major advantage in shooting.  But I had multiple short strokes when shooting the Larue.  I fired an additional 12 rounds at another target trying to diagnose the issue and trying out the offset sights.

The Larue lower is the only one of the bunch that isn’t ambidextrous.  I find the bolt catch on it harder to use than the one on the 901.  Not hard on its own, but less easy than the 901.  The receiver extension on the Larue is AR10 pattern, but doesn’t have the hole locations to collapse the stock completely.  The photo above shows the stock as closed as it will go.  This made the UU kit rifle longer than the others.

The Safety Level that Larue includes in their parts kit is horrible.  I have two of these Larue safeties and they don’t move positively.  Several times when I was bringing the rifle up for a fast aimed shot, attempting to flick the safety off it would only move half way.  I did not have any issues with the safeties on the other rifles.

The recoil spring on the Larue is much lighter and easier to work the action than the other two .308 rifles.  Felt more like racking a standard AR15.  When firing the action felt like it moved much slower than the other rifles.  I think this also made it feel more controllable and easier to shoot well it – when it worked.  Compared to the others, shooting the Larue Ultimate Upper kit felt like shooting one of the other rifles in slow motion.  I’m going to start calling this the LTUU762 for Larue Tactical Ultimate Upper.

Unlike the others, the KAC SR25-EC uses a rifle length gas system on the 16 inch barrel.  I had always heard that the KAC SR25 were so extremely smooth shooting.  Much to my disappointment it didn’t seem any better than the others.

The SR25s for a long time not have come with ambi controls.  The right side safety is scalloped and the rifle has a right side bolt release.  The rifle weighs about 2 pounds heavier than the other rifles.  This was noticeable in the handling and recoil characteristics.

When shooting the SR25-EC it recoiled straight up.  Settles right back down on target.  To me it seemed like it had similar recoil to the 901, but the 901 is about 2 pounds lighter.

I think it was the lighter two stage trigger on the KAC that helped me shoot it rapidly better than the standard AR15 trigger on the 901.

So?

Right now, if I had to pick one for a fight it would be the 901.  Even thought I shot it worst in this side by side comparison, it is far lighter than the KAC, and the LTUU7.62 is currently unreliable.  I previously had a Warcomp and match trigger in the 901, and it drastically reduced recoil and made it easier to shoot.  I returned it to stock before this comparison.

I’ll be talking more about these rifles in the future.

A look at the 5.56 Larue Ultimate Upper

Some years back I wanted a Larue Tactical PredatAR upper.  They didn’t sell the uppers separately so I bought an entire rifle and sold the Larue lower.  I sold the lower for $500 and it sold in 15 minutes.

Guess I should have priced it higher.

At first mounted a muzzle break on it, and while that pretty much eliminated recoil on that light gun, but made for a gun I didn’t really enjoy shooting.

Later, I replaced the Surefire MB556 break with a Warcomp and the upper quickly became one of my favorite setups.  I later had it Cerakoted.

Light weight, smooth shooting, and accurate.

 

So I wanted more like that.  First, a similar rifle in .308.  So a while back I picked up a Larue 7.62 Ultimate Upper kit.  I ordered it about 4 months ago, I also ordered a lower to go along with it, which I am still waiting on.

I thought about picking up a second PredatAR.  But I saw there was the newer cheaper Ultimate Upper line.  The Ultimate Uppers are the newest in Larue Tacticals line.  You get a customizable kit including everything except a lower.  You have a variety of caliber options, barrel lengths, profiles, etc.  They have small frame options (AR15), and Large Frame.  In the Large Frame they have SR25/AR10 options and DPMS pattern.

So while the Larue 7.62 Ultimate Upper is pretty useless to me until Larue Tactical gets around to shipping me a lower for it, I have been really impressed by the kit.  So I bought a Larue 5.56 Ultimate Upper.

 

Unfortunately I wasn’t smart enough to snap photos of the 5.56 kit when it arrived.  So here is a couple of the 7.62 kit.

 

The 5.56 kit was similar.

I dunno why, but I decided to go with the standard weight 16 inch 5.56 barrel instead of the lightweight PredatAR profile.  I choose the MLOK over the Keymod hand guard option.  It seems to me that MLOK is winning the modular handguard war.

 

Larue added some sort of additional seal on the gas tube and gas block.  To quote Mark Larue, “It’s the new style – gas leaks bug me.”

The hand guard profile is quite small and narrow.

The upper kit was quick and easy to assembly.  I replaced the Larue muzzle break with a Surefire flash hider mount.

I initially threw an Aimpoint on the upper, made for a pretty handy configuration.

But I decided for the second outing that I would throw a Leupold MK6 on it and see what it could do.  I found I had a few rounds of Black Hills 75gr BTHP Match left, so I gave that a try.

I fired 3 rounds of M855 to get on target, then a couple of 3 shot groups (as I am very low on Black Hills match ammo).

Shooting at these 3/4 inch dots at 100 yards, my two quick 3 shots groups measured about 7/8 and 3/4 inch respectively.

So, I think it has potential.  I am going to have to do some more shooting for groups with this upper before I decide how it is going to be set up.

If the Leupold MK6 were to stay on it, I would move it forward as I prefer to shoot nose to the charging handle and I can’t do that with the current setup.

I really like the UU upper, and I think it is a great deal.  But I do need to point out a few things.

The UU upper is like a budget high end gun.  Larue changed the profile of the upper to something quite angular, most likely for ease of machining.  Less steps in the mill means faster and cheaper.

This angular profile is new to me.  I can’t think of anything similar from other brands.  The VLTOR MUR was similar, but didn’t take it to this extreme.

So, for example, it doesn’t have any profiling to blend into the curvature of the rear of the lower.

And the chamfer is extreme enough that there is a gap between the upper and lower above the mag catch.

So, if you are one of these nuts where fit and finish is the final say on if you like a firearm or not.  You have to decide if these little things would bug you.

Buying a UU upper lets you order a Larue lower.  But apparently on the factory assembled rifles they hand match the uppers to the lowers.  If you buy them separately with the kit, that won’t happen.  So once again, if you are a fit and finish freak, caveat emptor.

If not, I think the UU upper kits are a tremendous deal.  It does take away from the fun of picking each part your self, but you know you are getting quality and parts that will work together.

I really like mine.  Enough so that I ordered a Larue lower to go with it.  Now it is just to see how many months it will take them to ship it out.

Interesting Picture

I stumbled across this photo online.  I have no information about it other than the photo.  I saw it was referenced on a couple of forums I don’t have access too.

For all I know it could be airsoft, but lets imagine for a moment that we know it isn’t.

I used to hear that women could tell a great deal about a person by their shoes.  I’m not a women, so I have no idea if that is true or not.  But you can tell a little about a person by their weapons.

Lets take a look at some of the oddities of this weapon first.  Well I suppose we should look at the basics first:

It appears to be a HK416 or a cut down/rebarreled MR556.  The photo is somewhat blurry so I can’t tell if there is a third pin for full auto or not.  It has a Geissele scope mount which means this is a newer photo, but it appears to have a very old Surefire 4 slot flash hider.  This seems to imply the user has been using an old Surefire 556K for a long time.

Correction, it has been pointed out to me that it is the newer 212A 5 slot flash hider.

I’ve heard rumors of the combination of the old 556k and the 416 destroying guns.  I have no idea if this is true or not, when I had MR556 uppers I never ran them suppressed.

Back to the topic.  This rifle appears to have one of the new Nightforce 1-8x scopes which are pretty new.  That scope is sitting in a Geissele scope mount, which are said to be very good (and are extremely expensive).  I find it extremely ironic that this ultra tough non quick detach scope mount has been set on top of a LaRue QD riser.  This tells a few things.  The person who set this up wanted or needed the scope higher and/or needed the ability to quickly remove the scope.

They they didn’t just use a taller Geissele or Larue mount I don’t know.  If this is an issued firearm and they are using an issued Geissele scope mount this would be an example of the the wrong equipment being selected for the end user.

 

Then there is another aspect I find interesting.  There is an offset Aimpoint T-1, while the rifle has a 1-8X on it.   Aside from the offset T-1 and the light tape switch hinting strongly the the user of this rifle is right handed.  It also implies that they feel that switching the scope to 1x is either inferior or slower to just rolling the rifle and usign the offset T-1.  If they didn’t feel that way it would be unlikely that they would have the additional weight and cost of the T-1 on their rifle.

This person then is also doing something that warrants having 8x magnification on their 10.4 inch barreled rifle.  If it was simply for observation the user would most likely just carry something like a monocular or binocular.  Instead this person can use the 8x magnification on their rifle.

 

But my two biggest things I found interesting in this photo.  That the 1x on the 1-8x is some way insufficient and warrants still having a T-1.  That the Geissele scope mount is either too low or not QD and needed to be set on a Larue QD riser.

 

My first SBR.

A long time ago, in the ancient barbaric times of 2007, I finally had an approved Form 1 to make a Short Barreled Rifle (SBR).  Back then we didn’t have the pistol braces so doing the paperwork for a SBR was considered the best way to go.

I don’t remember why I choose to go get a SBR, but I have loved the short AR15 ever since.

I decided no expense would be spared, I would build a top notch SBR.  (Tier 1 wasn’t a phrase used back then, but that sort of mentality).

It was common knowledge back then that short AR15s were generally unreliable.  The LMT 10.5 inch upper was said to be the exception.  That it would “run like a raped ape”.  (It wasn’t till years later I learned that was a racist term).  LMT also used a medium profile barrel heavier than a standard M4 barrel on their 10.5 inch uppers.

I wasn’t going to use my old RRA lower for this, I would buy a brand new top of the line lower to build this top of the line gun.

So I went with a LMT lower.  The gun ended up looking like this:

Let me take a moment to explain some of the decisions and setups shown.

I wanted a flip up rear sight, so I went with the Troy rear sight I purchased for use in Iraq.  Troy sights are still an excellent product, but I much prefer to use other brands now.  Not to mention that the Troy Industries has done some questionable things since then.

I wanted to free float the barrel so I had a Larue 7.0 free float rail installed by MSTN.  It made for a very nice configuration.  Back then I wasn’t set up to build uppers, and MSTN was very highly regarded.  I believe they are still around but I don’t hear much about them.  I had him test fire the upper for me.

“YOURS IS BUILT AND GOT SHOT YESTERDAY. A FRIEND AND COWORKER WAS THERE
AT THE RANGE, AND I LET HIM SHOOT A MAGAZINE THROUGH YOUR UPPER.

HE ON THE SPOT DECIDED TO GET ONE FOR HIMSELF. HE WENT AND PICKED UP AN
LMT LOWER FROM THE SHOP WHERE WE DO BUSINESS AND HAS ALREADY SENT IT
OFF TO BE ENGRAVED.” Quote from Wes.

I choose to use a Diamondbond coated LMT Bolt.  MSTN was out of Diamondbond coated LMT Bolt Carriers so I purchased a coated Young MFG carrier.  I also purchased a second coated Bolt Carrier Group.  I’ll come back to this detail later.

A PRI Gasbuster was picked as it was the ultimate charging handle of its day.

I used the SOPMOD stock that came with the LMT lower.  I added a KAC QD sling attachment to the stock as back then LMT stocks did not offer a QD mount in them.

I used a CQD sling for a while back in Iraq.  I decided to go with CQD sling mounts on my SBR.  It was a good while later that I learned the SEALs were using the same mounts, I still think they were copying me.

Back then I think I tried every mainstream AR grip on the market. (No I didn’t use the one that let you put a revolver grip on your AR).  I eventually settled on the old A1 grip.  No finger bump.

For a while I ran the Eotech 512 forward mounted because the weight up front also helped reduce muzzle flip.

 

There were many many things I loved about that configuration, but it had a few fatal flaws.

Lets first talk about mistakes I made.

The LMT lower I purchased had an issue with its finished.  It was flaking off near the safety and the trigger pins.  I should have rejected it and had it replaced.

That sorta worked out ok with due to another mistake I made.

I had a local trophy shop engrave it for the NFA engraving requirements.  They really fucked it up.  I ended up having a pay more to send it off to Orion/TheGunGarage to have it properly engraved, the bad engraving fixed, and the lower finish touched up.  They work they did was awesome, but I shouldn’t have had to have that work done in the first place.

Back then some of the ammo I shot was Norinco.  This Chinese ammo seemed to lack the flash suppressant than most American ammo has.  When I fired my first round through this upper it made a tremendous amount of flash and blast and I instantly knew I was going to get a suppressor.  I wanted a Knights NT4, but my local didn’t didn’t have one and I let them talk me into a Gemtech M402.  The M402 is a good can, but ultimately wasn’t what I wanted.  Had I bought a NT4 I would probably still be using it as my main can today.

One of the biggest mistakes of mine was picking Eotech.  Back then, it was common knowledge that Eotech was great and Aimpoint sucked.  Just like how it was common knowledge that the world was flat.  Everyone knew that Eotech sights were faster, and because it used common AA batteries you could pull batteries of a remote to keep it running.  I didn’t know back then that I would have to room clear to the living room TV remote just to try and keep the Eotech running.

Now lets talk about the issues outside my control.

I had two Diamondbond LMT/YoungMFG bolt carrier groups.  One has been flawless, has seen tons of rounds, and just held up awesome.  It still resides in my favorite AR.  The other is. . . finicky.  That other coated LMT bolt causes random malfunction in what ever gun it is put in.  I was never able to figure out why.  It still sits in my parts bin.  That carrier however has seen tens of thousands of rounds of 5.45 and held up awesome.  Diamondbond is an amazing coating.

Chrome lined barrels can be very accurate.  LMT can make a very accurate barrel.  But my barrel was threaded poorly.  This wouldn’t have been an issue except I wanted to run a suppressor.

Either way this barrel had massive point of impact shift when suppressed.  10 minutes of angle.  That meant that I could either zero the upper suppressed or suppressed.  Since then I have multiple barrels that have had zero POI shift when suppressed, and that is what I have grown accustom too.

That was the ultimate deal breaker for me.  To not be able to quickly switch between suppressed and unsuppressed.  But I still love the 10.X inch barrel length on the AR.

Optic of the week – SU-231/PEQ Eotech 553

Around a decade ago it was common knowledge that Eotechs were faster to use and better than Aimpoints.  Just like how not very long before that it was common knowledge that the Earth was flat.

The Eotech sights use a laser to project a hologram of the reticle in the optical window.  This allows for a greater variety of reticle patterns then a diode sight like the Aimpoint.  Most common in Eotech sights are a 1 MOA dot with a 65 MOA circle around it.  A downside to holosights are shorter battery life.  Battery life on the Eotech is advertised to be about 1000 hours.

There are other variations with additional dots to function as a drop chart.  There are also machine gun reticles.

For the life of me, I could not get the reticle to show up nicely in a picture.  Despite how it looks in the photo, the reticle is bright and easy to see.  If you focus on the reticle, you will see that it is comprised of a bunch of dots, it will appear to be fuzzy if you have the brightness cranked up.  That is just due to the nature of how it works.

Windage and Elevation is easy to adjust using a coin or similar tool.  Both adjustments have positive clicks and are easily accessible on the right side of the sight.

Brightness is adjusted using the up and down arrow buttons on the rear of the sight (there are some models where the adjustments are on the left side of the sight).  If the sight is off, hitting one of these buttons will turn on the sight.

The Eotech will automatically turn it self off it preserve battery life.  Turning it on by hitting the down button will have the Eotech turn off after 4 hours.  Hitting the up button will have it off after 8 hours.  Holding both buttons will turn the Eotech off immediately.

Some models, like this 553 have a NV button that will dim the optic for night vision use.  While you can sorta get away with using most optics with night vision by using a dim setting, that can damage nightvision over time.  NV setting reduce the brightness enough so that you will not damage your expensive night vision device.

I did some shooting with this Eotech and with a Aimpoint T-1 on the same rifle.  Shooting from the bench, or rapidly engaging multi targets off hand was quick and easy with either optic.  Both were fast and easy to use, but I would not say the Eotech was any faster or easier than the Aimpoint.  The only real noticeable difference in use was that this Eotech 553 felt much heavier on the rifle than the T-1.  Looking at the stats on them, the Eotech is about 3 times heavier.  That is an additional half pound on the rifle over the weight of the T-1.

I used to be a major fan of Eotechs.  But over the years I saw multiple Eotech Holographic Weapon Sights fail in various ways.  Battery terminals would break, I’ve seen the prism break loose.  Lenses delaminate, and reticles dimming.  The biggest issue was that many Eotechs would drain their batteries even when off.  I found that my Eotech 512 would drain the batteries even when off.  I had to store it with the batteries removed.  I felt the high failure rate of Eotech sights was damning on its own.

Turns out it gets worse.  L3 was aware of issues with their like of Eotech sights, and were covering it up.  L3 paid a settlement of 25.6 million dollars over this.  The biggest issues they were covering up were that the sight wasn’t actually parallax free and that there could be massive zero changes if the optic was exposed to temperature changes and it turns out that Eotech sights also were not as waterproof as they are suppose to be.

Despite these persistent issues, you still see fans of Eotech sights defend them online.    The most often statement in Eotech’s defense is that the Navy SEALs are using Eotech sights.  I point out that the SEALs use what they are issued, are the individuals are not purchasing these out of pocket.  They also have far more range time and funding so doing stuff like rezeroing before a mission or replacing batteries each mission is a non issue.  But even NSWC Crane had to issue a Safety of Use Message about the Eotech warning about a 4 MOA Thermal Drift problem, fading and disappearing reticles, and 4-6 MOA parallax error.  SOCOM acknowledge these sights have issues.

So if you want a known substandard sight, buy Eotech.