The Evolution of an AR15


Bartholomew Roberts
April 23, 2007, 07:07 PM
The first AR15 I owned was an Olympic AR15 Carbine with a 11.5" stainless steel barrel and a 5" flashhider. I bought it in 1989 mostly because I thought it looked cool. Unfortunately, I was forced to part with it to pay the bills as a poor college student.

When I did eventually have the money, I purchased a Bushmaster 16" HBAR carbine. I was a little older and wiser by then and more interested in having a fully functional barrel than the looks.

I liked this rifle a lot and it was accurate and reliable. I changed the A2 sights to the improved battle zero, replaced the older carbine stock with a new M4 Enhanced telestock (shown in picture) and in an effort to spare my hands from the heat generated by semi-autos in the Texas summer, I added genuine Colt M4 handguards. I took my first course of formal instruction where I paid someone to teach me about a rifle at Texas Pistol Academy.

We shot in a variety of scenarios and I encountered some limitations of irons in practical use. I soon purchased a TA11 and mounted it to the carry handle. I also changed the grip to a more palm-filling Sierra Precision grip. It actually worked suprisingly well; but part of me still wanted a flattop to see if it was better... so I went to this:

It was better in some ways, so I kept it. I added an ARMS #40 rear sight to make sure I could use irons when I wanted to and and ARMS #19S mount so I could remove and replace the ACOG easily without changing the zero (a big pain for the carry handle mount). After taking a course from Chris Grollnek, I realized that a more substantial charging handle would be a big help, so I added the PRI Gasbuster.

The course with Grollnek (where we shot 800rds in a day) convinced me there had to be a better way to deal with the heat the barrel generated. The M4 handguards insulated the hand; but they trapped the heat next to the barrel and kept it warmer. Reading up on the subject, I became convinced a Knight's free-float rail system would give me cooling, better accuracy and a place to attach a light. I also was looking at a new experimental stock from a company called Magpul. The cost was enough to make me want to gag; but the prototype was getting good reviews so I bit the bullet and bought one, fully expecting to return it soon.

As it turns out, both purchases were good ones. The Magpul M93 turned out to be one of my favorite AR15 accessories (the TA11 is THE favorite). Also, I immediately noticed an improvement in group size (about 0.5" at 100yds) and cooling after the Knight's free-float rail was installed.

This was about everything I wanted in a rifle. I started shooting in informal 3-gun competitions and soon was working the rifle out at ranges from contact to 600yds. I was amazed at how versatile it was. However, as work claimed more time, my skills fell off and it soon became time to polish them up, this time with Primary Carbine ( at Tac-Pro Shooting Center ( ).

Even with my skills honed, I wasn't getting the results I used to at longer ranges. The fact that this coincided with a burning desire to get a new barrel was purely coincidence (seriously, the barrel was having some problems at range). I had recently shot a friend's Armalite midlength and was impressed at the handling. I really wanted a midlength barrel; but that would mean changing the rail system too and that was just too much money. I decided to go with a carbine gas system on the new barrel. However, when the barrel maker shipped a midlength barrel by mistake, I took it as a sign and went ahead and replaced the Knight's free-float with the even lighter Daniel Defense rail. While I was at it, I also went with a PRI folding front sight. I didn't really need the folding front sight; but I really liked the MP5 style front sight with circle hood.

Sadly, that barrel didn't work out as well as I had hoped; but the manufacturer stood behind his product and fully refunded my money. I used some of that to upgrade the rear sight to a Troy and change the ACOG mount to a Larue. Both were still doing their jobs well; but at this point I had seen enough ARMS products fail that I just didn't feel comfortable with them anymore. I decided to go with a more traditional barrel and turned to MSTN which had never failed me in the past for this rig:

This rifle has been as close to perfect as I could want. There have only been a few things I can think of that would make it better. This is one of them:

You can find more on the suppressor here ( That is how the rifle looks as of April 22, 2007 - almost 10 years after I started modifying it. There are still a few additional things I would like to add - a Magpul UBR stock is high on the list; but it really is to a point where there isn't much more I would do to it.

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April 23, 2007, 07:47 PM
It's like watching a child grow up :)
Good looking bangstick! That's how I want mine to turn out when it grows up.

Man With A Gun
April 23, 2007, 08:26 PM
I am a lawyer and loved your pics of the AR.

I have a left handed STAG ARMS AR which is hell of a lot better than what I was issued in 1964.

April 23, 2007, 10:50 PM
They sure do evolve don't they. I don't think I have one that's in the same exact condition as they were when I first acquired them.

However, I found a few of mine have started to move back to simple again. The rails have been taken off and sold, the fixed carry handles returned, and even fixed stocks(albeit shorter ones) found their way back on there.

Just today I was considering turning one of my 20" ARs back into a flattop because I have a scope with an AR mount and nothing to mount it on except my 7.62x39 carbine. :(

Bartholomew Roberts
April 23, 2007, 11:10 PM
However, I found a few of mine have started to move back to simple again.

I'm actually going the other way right now. I have a few basic ARs that I built using the leftover parts (like the original A2 receiver) from the AR I am modifying.

I rarely shoot them though. I always end up bringing the modular ARs because if I want to do simple, I just pull all the stuff off and flip up the irons. You can always go simple with a modular rifle; but you can't always easily add stuff to the non-railed rifles.

This rifle is nice, simple and lightweight. With an SOtech light buckle, you have just about everything you need. However, if I strip off everything but the light from the rifle above, it too is nice and lightweight; but it also has a better sight picture, better stock, better accuracy and better cooling.

Bartholomew Roberts
April 25, 2007, 02:29 PM
O yes, the parts list on the flattop:

Bushmaster lower and fire control group
Bushmaster flattop upper
Lilja midlength 16" "Recce" barrel from MSTN
CMT bolt carrier group w/ "matched" bolt
Sierra Precision grip
PRI Gasbuster charging handle
Magpul M93 (first production version) stock
Magpul trigger guard
Ops Inc. two-port gas brake and 16th Model suppressor
Daniel Defense 9.0 (first generation)
PRI folding front sight/gas block
Troy same-plane folding rear sight
Surefire G2 in 1" Millet low-mount rings (That's right a $40 flashlight setup on an otherwise overpriced rifle ;))
Larue ACOG mount and TA11 ACOG 3.5x35 (donut)
Blue Force VCAS sling attached to Magpul sling plate and Knight's QD rail mount.

The slings (from oldest to newest pics) are: Boonie Packer/JP Patrol Sling, Specter Gear SOP 3-point, Specter Gear MOUT single-point, Blue Force VCAS. The only two I still have are the VCAS and MOUT. I like the VCAS better for most things; but the MOUT is superior for transitions to pistol and weakside shooting.

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