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My thoughts on the 6940

Yesterday Shawn posted about how the Colt 6940 series has been out for 10 years.

I remember reading about the 1040, seeing pictures of the prototypes, wanting a SCW, etc. But when the 6940 finally came out, I had thoughts similar to most. Why bother? Proprietary barrel, m4 profile, carbine length handguard. It seemed kinda silly. Even back then people were leaning toward longer handguards, different gas systems and barrel profiles. Colt came out with a product that didn’t match what the market was wanting.

Some years later I decided I wanted to get a factory Colt Short Barreled Rifle. The nice thing about SBR AR15s is that you can easily swap uppers to make it do what ever you want it to do. I was looking at buying a Colt 6933, when I found that I could get a Colt 6945 for far cheaper. So I did that instead. I am really glad I did.

Factory Stock Colt LE6945

I have long been a fan of the MK18MOD0 style AR15 configuration. I used similar setups long before I ever heard the name MK18. The 6945 is simply a better MK18MOD0. Lighter, with a monolithic upper and free floating barrel. Along with a folding front sight that is part of the gas block.

I really think it is one of these cases where something is better than the sum of its’ parts. Over a little time I ended up setting up the 6945 similarly to how Shawn had his 6940 set up.

I really love the simplicity and elegance of 6945. So when I got the chance I picked up the 6940 pictured above and set that up similarly as well.

It just works.

10 Years Of The Colt 6940

It’s hard to believe to me now but its been ten years since the Colt 6940 came out officially for sell. It was a pretty big deal at the time because it had been a long time since Colt had come out with a new variant of the AR15. The monolithic rail and flip up front site were something colt teased for years before it got in peoples hands.

You can see the gun above has a lot in common with the final version of the 6940. The gun pictured was submitted to the military for a possible future adoption. The early versions had a much inferior sling mounting system for the rail. You can see the stud on the side of the rail at the 3 o’clock position.

Various versions of this gun was shown at SHOT shows over the next years and scuttlebutt always claimed it would be out “later this year.” That was optimistic to put it mildly.

One of the models shown along side of those was the Colt “M5” pictured below. We never saw that. Thanks God for small favors.

Around 07, word was let out that the Colt “LE1020” was about to come out. It was so sure that some distributors and dealers started taking pre-orders. The 1020 was essentially the early version of the Colt 6940Piston. It seems at the last minute it was cancelled and refunds issued. The reasons and story will have to wait for another day.

One of the curious things of the history is this tantalizing model that many wish would be brought out even to this day. The Colt 6945 it was called at the time. Though it never came out and the colt model number was resused for another model, the 10.3 inch barreled 6940.

I am sure most of you reading this will immediately see this and wonder why it was not sold. No idea. It can be ordered this way if you are a LE org or the military, but so far that’s it. You can see the older style sling stud. As I said, the 6945 name went to another gun. Which Howard, lucky bastard that he is, owns an example of. Pictured below in all its glory.

Of course it is not the only SBR 6940 based gun. There is a 11.5 inch barrel and a 15.5 inch barrel. Also there was this little gem. The Colt SCW with a side folding stock.

In 2009 the LE6940 we now know came out and of course I got one nearly immediately. I was not let down. Since then I have been a 100 percent convert on the Colt monolithic upper. I think it is a major improvement to the gun and its accuracy is outstanding.

The 6940 in its stock form with match quality ammo and an optic makes an amazing and handy small precision rifle. I used this combo to shoot crows all summer out to 300 yards. There is just something immensely fun about shooting a carbine with a high magnification precision optic.

Over the next few years I used the 6940 constantly.

A few years later the 6940P finally came out after years of waiting. Below are the DI and Piston uppers compared. It is a very nifty design. The P comes with a SOCOM profile barrel and H2 buffer along with the piston operating system.

A full look and review of the 6940Piston can be found here on the site already so I won’t cover that again.

Since then a few other versions have come out. Noticeably the 7.62×39 variants for other countries who prefer to use an inferior service round.

You may have noticed the top picture shows a version that takes an AK magazine. That has been a foreign military sold model only at this point and it’s likely to stay that way.

Most significant to the spin off monolithic upper series is of course the 308/7.62NATO carbine 901.

Now after all this time. How does the regular old DI gun shoot? Still great. The free floated barrel and the unique system that attaches the barrel is incredibly accurate for a gun with a milspec barrel. Not to say they aren’t already more accurate than most people realize, but the free float monolithic upper brings it all out with match ammo. I placed 10X optic on my 6940 and shot some groups with it at 100 yards to show a general idea of just what they are capable of .

The carbine was shot from the bench off of bags. The leupold 10X was used and the SSA match trigger were able to make shooting a breeze. Really there is not much difference in accuracy between this and my MK12.

a selection of handloads and the more high end factory ammo

“flyer” is zeroing shot not part of group

The Colt 6940 is a real classic in my opinion and I have turned a lot of people on to them. No one I know has regretted buying these excellent carbine once they get them in their hands. It is a great gun now 10 years old and going and I highly recommend them.

A look at the Rail Scales LDAG

A while back I picked up a LDAG from Railscales. I had seen a couple of great reviews about it so I decided I wanted to try one.

It is bigger than your average handstop, but smaller than the stubby vertical grips. One side is 90 degrees from the rail and the other angled at 70 degrees. One of the major draws of this is that texturing on it.

The LDAG has a very grippy texture with out being sharp.

I’ve seen people claim that the LDAG (and similar) are not vertical grips because of the angle and that they are designed to be hand stops. Because of that some people will mount them to pistols, like this photo taken from the internet.

Photo was posted on AR15.com

Personally, I wouldn’t want to be the test case for the legality of that.

The LDAG is a very nice piece of kit. The only downside I can find with it is the cost. List price is $129.

In perspective, a stubby Tango Down grip is lighter, and half the cost.

Continuing with that example, if you take the cap off the TD Stubby grip, it is similar in length, and even lighter still. So if you don’t need the angle and form of the LDAG, there are far cheaper options to achieve the same goal.

Frankly, the LDAG falls into the “gucci gear” category of stuff. It is something you could live without, and the type of thing someone would buy mainly as a status symbol. For example, you guys all can see how awesome I am because I have one.

So if you want one, get it. If cost is a concern, there are plenty of cheaper options.

PSA EPT SBA3 Pistol Lower

PSA Part (1)

This is Part One, of a several part Palmetto State Armory (PSA) 10.5″ pistol build. This part will focus on the PSA lower, other articles will focus on the 10.5″ upper, parts kit and the completed build. This is my first experience with PSA products, so let’s jump right into the PSA AR-15 lower.

PSA 10.5″ 5.56mm Slant Rail w/ Flash-can Pistol


I purchased the PSA EPT SBA3 Pistol Lower while it was on sale. The sale was for 199.00 and had free shipping. Considering the SB Tactical SBA3 adjustable brace is about 150.00 dollars if you purchase it by itself, this is a screaming deal for a complete assembled pistol lower. The PSA Lower can be found here: (
https://palmettostatearmory.com/psa-ar15-complete-moe-ept-sba3-lower-5165448150.html). The lower also came with PSA’s Enhanced Polished Trigger (EPT) which is a slight upgrade on the trigger.  Of course Magpul grip and trigger guard also come on the lower and is pretty much standard with most manufacturers now.


PSA Lower Box

The PSA lower came in very simple and nice packaging. A padded box and a PSA sticker. Simple, no extras and straight to the point.  The small PSA box is nice if you want to store your lower for whatever reason.

PSA Lower in Box

Specs/Attention to Detail:

Over all the lower seems to be mil-spec in quality and materials and finish.  A few things stuck out to me when I first looked over the PSA lower. I was surprised to see, in a lower priced this affordably, STAKING. The end plate is staked into the castle nut. This is a minor thing but I think it is important and a sign of quality. There are several manufacturers that sell lowers far more expensive than the PSA’s and they do not stake the castle nut in place.

Castle Nut Staking (left)

Castel Nut Staking (right)

The next thing I noticed was the beveled magazine well. Another nice touch that makes feeding the magazine into the lower quick, smooth and easy.  The lower receiver is a low shelf receiver, so if you are someone who is lucky enough to have a drop in Registered Auto Sear (RAS), you should be good to go.

Beveled Magazine Well
Low Shelf

The last thing I thought was a nice touch is the Palmetto State Armory logo on the SBA3 brace itself. In the future PSA articles this will tie in nicely on other parts.  A small marking that shows PSA is tying in all the small details for the purchaser. This has no functional use but makes the buyers experience enjoyable in small matching details.  For someone who checks to make sure every part on a Colt rifle or other manufacturer firearm is marked or stamped properly, it is a nice touch.  Clearly PSA took the time to have  a conversation with SB Tactical to ensure this happened.

PSA SBA3 Marking


So let’s get down to what really matters, how does it function. Well the simple fact is 100%.  I have had absolutely no issues with the PSA lower. I have run approximately 750 rounds with the lower, which is not a lot, but a proper built and spec’ed  lower will probably never have issues.  I did change a few things with the lower. I replaced the PSA carbine buffer with an H buffer as I run an H buffer at the minimum on all lowers I have.  I also changed the MOE grip to a Magpul K-Grip as I like the angle better. The safety selector is audible, tactile & smooth when flipping from safe to fire and back.

I used several different AR-15 uppers on the PSA lower. All uppers function 100% with the PSA and I had no issues on the fit or function. The PSA upper I used can be found here: (https://palmettostatearmory.com/psa-10-5-carbine-length-5-56-nato-1-7-nitride-12-slant-m-lok-upper-with-bcg-ch-mbus-sight-set-5165449684.html).

EPT Trigger:

The EPT trigger is a mil-spec trigger but has PSA’s enhanced polishing and a Nickel Teflon finish. Both the hammer and trigger is polished and coated in PSA’s Nickel Teflon finish. Can you tell a huge difference from a stock mil-spec trigger? That is for you to decide. I compared the EPT PSA trigger to several Colt mil-spec triggers.  I could maybe feel a slight difference but all of the Colt’s had thousands of rounds through them. The PSA was smooth right out of the box, very little creep and the break was very nice. I have no complaints and because it was included in the price of the lower, I think it was worth it.  Fast and clean follow up shots felt like a well used, broken in trigger.


PSA EPT Components


At this price point, I see absolutely no reason why you should not pick up a PSA lower. Especially if you are looking for a Pistol lower with the SBA3 brace. Hell, pick up a few at this price. I am very happy with this purchase and it should serve me and you well if you choose the PSA lower. If you are in the market for a rifle lower the PSA rifle lowers are cheaper than the PSA pistol lowers. I have seen them as low as 120.00 dollars, depending on stock and grip. If you are building a pistol or rifle I would say you should give PSA a look, especially if you are on a budget.


Don’t over charge your mags

Saw someone mentioning about how they could stuff an extra round in their mags. This is bad thing to do.

Let us use the AR15 as an example. If you load 30 rounds into a USGI mag it can be a little more difficult to insert that fully loaded mag when the action is closed. In some newer magazine designs, like the PMag, extra space is given so that it will be easier to insert that mag when fully loaded.

The problem becomes when you stuff that extra round in, you not only use up that extra space, but can cause binding or other issues. For another example, I found I could stuff an extra round in the Beretta 21A magazines, which would cause the pistol to not feed correctly.

If you want more rounds, buy a bigger mag.