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.

Optic of the week: HK Diopter BUIS

Ok, I’m phoning it in this week.  I found these old HK BUIS I thought I sold long ago, and I found that the old article on them has all the images missing.

On the HK416/MR556 and their .308 rifles as well the optics rail is higher than the rail on a standard flat top AR15.  Because of this HK fixed iron sights are lower than standard height AR15 sights so they can not compatible to use together.  Not that you would want too.

Under the 200m aperture of the drum, there will be 1 or 2 dots.  If there is a single dot (like this one) the sight is calibrated for a 10.4 inch barrel.  If there are 2 dots, it is the model for the 14.5 and 16.5 inch barrels.

HK Front sights are not adjustable, all zeroing adjustment is done on the rear sight.

The drum apertures are different sizes and set for 100 to 400 meters.  The 100m opening is much larger than the other ones to make it easier to use for close quarters use.

Windage is adjusted by loosing the screw on the top of the sight, and turning the screw on the right side of the sight.  1 full turn will move your point of impact 6 inches at 100m.  Tighten the top screw to lock the sight back in place.

Inside the drum there are two tabs.  Compressing both tabs inwards allows for the drum to turn adjusting the elevation of the rear sight.  You need to turn the elevation drum in 1/4 turn increments for 1.5 inch adjustment at 100m.  If you don’t have the proper sight adjustment tool, you can make adjustments using a pair of needle nose pliers.

Zeroing these sights can be annoying.

They are nice sights, and if you are more familiar with HK style sights than AR sights, it is nice to have this option.  However you can get good AR sights for cheaper that will have a finer and easier adjustments.

Brownells 308 Barrel Extension Torque Tools. . . sucks

I have a Geissele AR15 reaction rod and while I think it was pricey, I have gotten my moneys worth out of it.  Since I bought it the price has gone up to $100.  If I had to replace it I would probably just buy the Magpul BEV Block at half the cost.

Recently I wanted to get something similar for the 308.  The Geissele AR10/SR25 reaction rod is $200, which seemed a little high to me for a splined shaft.  So I looked around and saw that Brownells had a knockoff for $50.  At one quarter the price I quickly purchased it.

I learned the catch.  I guess Brownells wanted to change the design to avoid copyright or patent issues, so they removed the vise flats and put in a square drive.

Their instruction tell you to put muzzle device or barrel nut wrench in the vise, install a torque wrench or breaker bar into their reaction rod copy, slide their reaction rod knockoff into the action, and precariously balance the upper between your wrench in the vise, and the wrench in the reaction rod knockoff, and torque it all down with out dropping anything.  Good luck with that.

I found I could sometimes clamp the round rod in the vise tight enough that I could use it like a Geissele reaction rod.  I finally ended up just milling some flats in it so I could secure it in a vise.

Unless you have the capability to put a flat on the Brownells tool, I’d recommend passing on it.

Optic of the week: Leupold MK4 3.5-10X40

Long ago when I used to read about firearms, when the term “sniper scope” was said, is was probably referring to the Leupold MK4 series.

I was going to write some history, but instead I am going to quote, Dyspeptic Gunsmith who summed it up nicely.

40+ years ago, many consumer-grade were notoriously unreliable.

Oh, they’d claim to be water-sealed, but you’d dunk them in the bathroom sink and see a steady stream of bubbles come out of them. You’d put them on a heavier-recoiling magnum and you could see the zero walk all over the place – I even had a scope in the early 80’s, which, when mounted on a “mountain rifle light” ’06, had the reticle obviously come loose inside the scope.

There were all manner of issues with the less expensive scopes 40+ years ago.

Leupold commanded a premium because of their no-BS warranty – and quality. Being able to send a Leupold back to the factory and they’d fix it – for nothing other than the shipping cost to send it to them – was a huge reason why so many people who could afford the price chose Leupold as their scope of choice (modulo the specialized scopes like the Unertls). The European scopes were ferociously priced out of the range of most shooters in the US, and they were both rare in the market and difficult to support.

I remember reading one guide saying to buy WWII surplus scopes because they were build better than anything available on the commercial market.  I doubt anyone sane would agree with that statement now.  The glass coatings on the cheapest of Chinese scopes now outclass anything available then.

But back to the topic at hand.

Leupold offers a massive variety of scopes and variations of their scopes.  Different reticles, turret options, finishes, etc.  I don’t know if anyone offers any where near as many different options as Leupold does.  This also means many different versions of the same scope.

Cheaper 3-9x were often seen on hunting rifles, the higher end MK14 3.5-10x was seen commonly on competition and police sniper Remington 700s.  An illuminated version of this scope was used on the M110 sniper rifle.

Rule of thumb back then was that you wanted the 1x time the distance in hundreds of yards for the amount of magnification you would use.  So it was figured a 10x scope was what you needed for 1000 yards.  I recall seeing the Leopold 3.5-10x, 4.5-14x, and the 6.5-20x as the most common scopes among “serious” shooters for a long time.  Slowly other brands took over that market share, Nightforce being one of the major ones.  You could get the scope with a fine duplex reticle and target turrets or coarse adjustments with a mildot.

For example, on this particular scope the elevation are 1 MOA clicks and 1/2 MOA windage clicks.  The idea behind the coarse elevation clicks is to allow a sniper to very quickly adjust for distance.  Elevation knobs are also marked for bullet drop.  This one is marked 168 grain .308.  You can have Leupold make you a custom marked turret.  Some of these scopes that were used by the military have a BDC cap for M118LR out of a 20 inch barrel.

I’m going to omit going into the specs and stats of this scope as it is no longer in production to sell to the public.  Due to continued demand from law enforcement and military, Leupold will make these if they special order them.  Apparently Leupold would prefer if you switched to one of their newer and improved designs, but enough agencies out there want these classics.

This can be a good deal for you.  If you keep your eyes out you may find used Leupolds for sale by people have to have upgraded to newer scopes.  These older scopes have plenty of life left in them.


The .30-06 Government , or  US Caliber .30  is a a classic round everyone knows. I think it has probably been used for everything you can use a rifle for at one time or another.  It was the US service round for a million years before being phased out.    It had several different martial loadings over those years one of them being M2 Armor Piercing.  Unlike the M2 ball which was a FMJ bullet of about 150 grains, the A.P. load was a 165 to 168 ish grain  bullet constructed to defeat light armor.  The M2 ball round was not very accurate and because of the lack of accuracy even in match rifles,  military personnel during war times developed a tendency to just us AP ammo for everything.

The odd part of this is that during WW1, the AEF in France was unhappy with  effective range of their machine guns and ammo.  The lighter bullet   of the then service round did not give them the same range as the heavier German service round.   So the Army developed the heavier 174gr  M1 ball round.  This gave the machine guns a longer effective range and same with the service rifle.     The M1 load was also very accurate.   It was so accurate at longer ranges that the Army griped about the new round causing safety issues on firing ranges.   So the decision was made to make up ammo that was for use on the ranges set up for the older M1906  original load for use on the various ranges.     Shooters liked the lessened recoil of the lighter ammo made up for the restricted range distances, soldiers could carry more for the same weight etc etc. So a suggestion was made and implemented that the new round be substituted for the M1 service round and after some tinkering it was finalized as the M2 ball round at 152 grains.  By that time all of the experienced machine gunners and rifleman who  had been in WW1 and witnessed how poor the lighter load performed were gone from the service.     Once again when WW2 started  the M2 load showed its limits  and the tendency to just use M2 A.P. for everything became widespread.

So how accurate was the M2 AP service round? Having a large amount of US M2AP on hand and realizing most shooters do not have a place or range that would allow use of AP ammo, I decided to do some testing.   I  fired the ammo mostly in the M1 Garand which is the rifle most associate with the round and fired it the most. I also used a M1903A3 and to try to really get to brass tacks I pulled some off the bullets and reloaded them into federal gold medal 3006 brass and 308 brass and shot it for group.

First I fired 16 rounds through an M1 Garand  at 100 yards from a bench with bags.  Very good group considering the accuracy requirements of the ammo and the  “experience”  this M1 has.  The heavier load did produce slightly more recoil compared to the M2 ball 152gr load but not much. I have always thought the M1 Garand was comfortable and pleasant to shoot  anyway.

Next at 100 yards I shot the  M1903A3  using the AP bullets I pulled and carefully loaded into Federal Gold Medal brass. I used all the same care and procedure I would use  had I been loading match ammo.  I fired 8 rounds instead of 10  for no reason other than I pulled 8 bullets from  M1 clip and I did not have much match ’06 brass anyway.

Lastly at 100 yards I fired 10 rounds of   308 I handloaded using the M2 AP bullet loaded into Federal gold metal match.    I didn’t even play with the powder or do more than pull the bullets of the M2AP, then pulled the federal 168 grain GMM and then re seated the AP rounds into the gold metal brass using the factory powder and primer and virgin brass. I guess you could call it a reverse “Mexican Match” round.     And hey! it did pretty good!   Some times being lazy pays off!      I was glad this worked because I had loaded 100 rounds of my reverse Mexican match already.

Now I debated a long time at what longer ranges to try the M2AP at. I finally decided to restrict it to 200 and 300 yards. At least for the time being and  how popular this post is.   The reasons being that the M1 garand used for this does not have a new or  nearly new barrel, I can’t see tiny aiming points much beyond a few hundred yards well enough to shoot the iron sights on the M1 because of my eyes and the size of the rear peep and I had no idea how accurate it may be. I also used a man shaped qualification target since  the gun an ammo were made to shoot  men, who are conveniently enough, the same size and shape of man sized qual targets.   The results pleased me and if it is asked for by readers  I will repeat the test at 500 and maybe 600.

So there are the groups at 200 and 300 yards.      You did not count wrong, one round at 300 yards did not hit the target.   I found that the M1 Garand is like some  other semi autos and sometimes the first round chambered by hand does not always shoot to the same point of as the rest of the group cycled by the guns action during recoil etc.   Not too bad I think for an old Garand with a well used barrel and military ammo from the 40s.