Retro CAR-bine

Retro CAR-bine

Posted by Dan Rogers formerly of Guns and Gunsmiths on 6th Aug 2021

Retro CAR-bine

A few months back I wrote an article on a retro AR project where I set out to replicate the M16A1 rifle my dad carried in the Army. In doing so I seem to have opened a can of worms. The project made me debate a retro carbine project. My dad occasionally carried a CAR15, hence the spelling of my title. CAR15 was a catch all term that applied to carbines the military carried before the M4 existed. Since my dad’s carbine was a 10.5-inch barreled carbine, I shelved the project not wanting to obtain the tax stamp needed for the SBR. However; about three months ago my wife brought home a shiny new gunzine for me. I suppose I had been well behaved enough for her to bring me a treat from her outing to the bookstore. On the cover was at what first glance seemed to be an M4 carbine. Closer inspection of the photo revealed something a bit more unique than your standard M4. It seemed eerily familiar with its A1 lower, C7 receiver, XM style stock, and M4 contoured barrel.

I read the article and figured out the carbine was a Colt 723 carbine replica. This carbine was one of the stepping stones in the long line of succession from the earliest carbines to the M4s we know today. I have four of them in a photo for a little clarification. These four are probably the closest to the M4 we know and love today. Starting with the 653 and 654 and spanning to the 727. The 653 and 654 I believe were the last of the all A1 component carbines, and the 727 is virtually a dead ringer for the M4. The 723 falls somewhere in the middle and uses a unique C7 receiver. A C7 receiver is basically an A1 with a shell deflector. I think they have a really unique look combined with the M4 barrel. The 723 is the carbine I remember from photos of special forces guys in different operations spanning the globe from places like Panama, Somalia, and Iraq. After realizing this I knew I had to have one, but my word did this particular company want a lot of money for them!

I thought surely, I can build this thing, and I knew just where to turn. I immediately emailed my buddy Patrick at TNTE Sales. I knew he would know way more about them than I. He informed me that Top Notch Top Ends was going through some changes in their product line. In an effort to find their niche, they were gearing up to offer all retro and mil spec AR parts and uppers. They had already begun the process of lining up different suppliers for specific parts, so my timing on the project was impeccable. After discussing the carbine specs, we found one of their uppers, that will be available after the first of the year, was a dead ringer. They call it an XM4 upper, and it is built on a C7 receiver with a 14.7 inch 1:7 twist barrel that is pinned and welded to satisfy minimum length requirements. Patrick agreed to allow me to buy one of these uppers before its actual release. Along with this I ordered everything I needed to assemble the rest of the rifle. I obtained a lower receiver from McKay enterprises, because NoDak Spud receivers were on back order. My lower parts and stock all came from TNTE Sales. I went with TNTE’s polymer XM stock. I have always been a fan of the XM stock because it simply looks “cooler”. I like the TNTE version of it so much that I put one on my M4! The poly stock costs something like $70, but it comes with the extension housing (tube), spring, buffer, end plate, castle nut, and stock. I think that deal is really hard to beat. The tolerances on the tube and stock are incredibly tight. Anyone who has handled either my M4 or this 723 remarks on how well the stock fits.

Apparently, Santa came early for me this year, and I am beyond pleased with how well the carbine turned out. I assembled my lower and popped on the upper. After function checks and some trigger tuning (AGI 335DVD if you need to know how-to) I rigged up a sling and mounted my scope. I used an old M16 sling and some 550 to rig what is sometimes called a silent sling. I only had my dad’s photos to go by and would welcome any critiques from you vets out there who know how to rig them. The scope is a Barska replica of the old Colt scopes of the era. I know most Delta guys used red dots, but I personally prefer a scope over a red dot, and one like this would have been in military inventory at the time.

Now the true test remained. How does it shoot? I decided on zeroing the irons at 50yds and my scope at 100yds. I made a REALLY quick range trip and was shocked at how well the little carbine shot. All I had on hand was some surplus Israeli 55gr FMJ and 77gr BTHP ammo. After zeroing I fired a .222” center to center 50 yard group with the 55gr FMJs. Moving out to 100yds with the aid of the 4x20 scope the carbine printed a .721” center to center group with the 55gr and an impressive .550” center to center shot group with the 77gr. All are 3 shot groups off a front bag only. Surprisingly the point of impact difference between the 55gr and 77gr at 100 yds was only 2 inches of elevation. The 55gr impacts centered but 2 inches higher than the 77gr. As always, your mileage may vary, but I was pleasantly surprised to say the very least.

This was a fun little assembly gig, and is most certainly a unique piece of black rifle history. If you would like to get your hands on one, they will be available after the first of the year through You can go to their site and click on the retro uppers in the categories column and see a whole host of different options ranging from A1 to A2 carbines and rifles of all sorts. If you do not see a combination you like, then you can buy the C7 upper with rear sight and dust cover and assemble what you want. You can have it your way and not have to worry about the 20 minutes of windage built in to some of the old receivers. All of TNTE’s retro receivers play just fine with new production parts vastly streamlining the assembly process whether they do it or you do. Either way you go I don’t think you can go wrong. They offer a quality product built by knowledgeable people who love what they do. I wonder what they will crank out next.