The Dalphon .50 AE AR-15 Conversion

By Jeff W. Zimba

Without a doubt, my favorite rifle is the AR-15. It is arguable that there are many others that perform better for specific tasks, but for an all around gun this brainchild of Eugene Stoner is a hard choice to beat. The number of new caliber conversions manufactured by Dalphon now opens the spectrum even more.

I have enjoyed the versatility of the AR family of rifles for many years. The number of configurations possible have always been limited only to ones imagination. My first one was an original Colt SP-1 with a pencil barrel and beavertail hand-guards. I stopped at a local gunshop with my buddy Tim and he looked it over for me. He started pushing pins and pulling parts, and eventually gave it the stamp of approval. He gave me a crash course in operation, care and maintenance, and the rest is now history.

Before this purchase, most of my firearms were more “traditional”. I grew up in the “gun culture” being surrounded with firearms of all sorts, but the vast majority were hunting rifles or target pistols. I always had an admiration for firearms and learned to shoot in the days before I was old enough to remember. My first exposure to “military style firearms” was when my father purchased a Bushmaster Pistol manufactured by Gwinn Firearms back in the late 70’s. I think this was my first true love. I wasn’t allowed to shoot it right away but I always knew I wanted to. Until that point I was only regularly exposed to firearms where it was common to fire 20 rounds or so, give it a cleaning and retire it until the next trip to the range. With this new addition came the necessity for big magazines and more ammo. This would prove to be the beginning of a life long hobby, and the basis for many future career choices. I know I have said it many times before, but once again, “Thanks Dad.”

In my early days collecting the AR-15 rifles, there were not many caliber conversions being marketed that I was aware of. They were almost all chambered for .223 (5.56x45) with a few 9x19 examples out there. The latter were fairly rare and definitely more expensive. Colt had a .22 Long Rifle sub-caliber unit, and Jon Ciener was marketing the Atchisson kit, but I was never really interested in stepping down in ballistic properties. The original Armalite AR-10’s in .308 (7.62x51) were very rare and expensive and were never a realistic option.

In order to satisfy my desire to study and collect these rifles, I was on a mission to buy every part for every configuration I could find. That poor SP-1 sported almost every stock on the market and the barrel lengths covered all the bases as well. The hand-guards varied from the original beavertails, to the A2 Style round ones, the carbine A2 style on the shorty upper and even sported the M-203 hand-guards when a flare launcher was added to the family. After a while it was just obvious that a new caliber was all that was left.

My quest was a lonely one without many options, but to anyone on this same road today Dalphon Manufacturing is here to assist you. I first met the folks at Dalphon at the Soldier of Fortune Convention a few years back. They had some pretty innovative products on display. I noticed their suppressors first, and after walking past their display a few times I noticed that the bore on a few of their AR barrels was a little “large”. I believe it was a 9mm upper I was looking at, but they had many more in the works. They have an impressive product line and the AR-15 caliber conversions are just a part of their business.

When they introduced their newest upper receiver chambered in .50 Action Express it caught my attention right away. I seem to have this foolish grin that washes over my face whenever I encounter a firearm with a bore of 1/2” or better and it was definitely present again this time. Someone had tried this conversion a few years back and it kind of drifted into the shadows but remained an interest of mine nonetheless. I remember reading about the massive muzzle energy and stopping power, and thinking it should be on my list to someday own one. I contacted Dalphon and they shipped a unit right out.

While waiting for it to come in, I did a little homework on available ammo. Back when the .50AE round was first introduced, it was as expensive as .50 BMG. If we could find it at $1.50 per round it was a good deal. I was pretty impressed this time when I picked up a few boxes of Speer Gold Dot for less than $1.00 per round. There are also many ammunition choices now, as where there were only two originally.

Since I also knew ahead of time that it would arrive in a “flat-top” configuration I started looking around for a suitable test scope. I contacted C-More Systems and they shipped me one of their Tactical Sights. This seemed to be a natural marriage, and when it arrived and was mounted, my suspicions were confirmed. It was perfect for the Dalphon unit.

When the gun arrived, I took it apart to see what made it tick. The most noticeable difference from a standard AR-15 was the barrel assembly. It is a heavy 16” stainless steel bull barrel surrounded by a round hand-guard. It is gas operated and utilizes a unique adjustable gas block. The gas block is moved foreword or rearward to adjust gas pressure. There are 4 allen screws that must be loosened and re-tightened when the block is in its desired position. There are currently 2 settings, one for hot ammo and one for regular loads, and it is my understanding that a fully adjustable gas system is in the development stages.

Some of the .50 AE ammo on the market creates much more pressure than other brands and this has made it necessary to bleed off a little gas to prevent damage to the firearm. Most often the extractor would be the victim of these hot loads and the easing of the gas pressure has evidently corrected the situation. IMI Ammunition is commonly a little hotter than many other commercial brands and the hot setting is actually stamped IMI.

I had done enough fondling and it was time to test it out. I mounted the C-More Sight and it surprisingly set almost dead center from the factory. The detail and quality of the C-More was amazing. Not only was it very functional and comfortable, but the aesthetics were incredible. They incorporate an E2 style “rear sight” into their design that looks just like a factory Colt unit. Everyone who examined the scope thought the “rear sight” portion of the scope was part of the rifle itself. The C-More Tactical Sight is a red-dot sight that also utilizes the iron sight for superior accuracy. Having used a number of red-dot sights over the years, and seeing few real improvements, I set my expectations low. I am pleased to report here that I was not disappointed, but actually very impressed with this system. Target acquisition is fast, and by using the dot in conjunction with the rear sight it is much more consistent than any I have used in the past. Thumbs up to C-More.

Due to all the stories I had heard about this particular caliber being fired in a 16” barrel as opposed to the much shorter barrel of the Desert Eagle pistol, I wanted to run it through a chronograph and alleviate some fact from a little fiction right away. We set up a Dillon chronograph and I loaded a magazine with Speer 325 grain Gold Dots. We wanted a string of five rounds to get an average reading. As soon as I squeezed the trigger the first time I knew this was not your typical AR. The average bullet speed was over 1,760 feet per second, and the recoil was very noticeable.

I had expectations of light to moderate recoil due to the very efficient buffer system, but these expectations were soon quelled. This bad boy has some thump! Now don’t get me wrong, it is not anywhere near severe enough to discourage you from shooting it again (and again...and again...), but you definitely know it is there. The sound is moderate, and the heavy barrel assists you in keeping the muzzle down a little bit when firing rounds close together.

There was a private shoot that would be attended by many seasoned Emma-gees coming up and I thought it would be the perfect place to get the “man-on-the-street” opinion of the Dalphon conversion. This was a shoot for the members of the Hiram Maxim group that work at the big Military Firearms Shoot & Expo every year, and was an opportunity for the crew to get a little shooting in. I had mentioned to a few of the guys that I may be bringing the Dalphon and when I pulled in I was asked right away of its whereabouts. When I pulled it out and started loading a magazine, an instant line began to form. When I set the rifle down and the bore diameter was visible, the line got longer.

I gave everyone interested a few rounds to fire at the appliance or automobile of their choice, and almost all the reactions were the same. After firing a couple rounds, they would typically rotate their shoulder or make some type of signal that they were aware of the recoil, and a big smile would wash over their face. When the line would quiet down, the first question I would get was “How much are these?”

When asked about their opinion of this combo everyone liked the C-More Tactical Sight, and all were intrigued by the massive bore of the rifle. When I asked about the recoil, almost everyone compared it to shooting a shotgun, and no one thought it was too excessive. The unanimous decision was it was certainly different than any other AR-15 family rifle they had ever encountered and all liked it.

I was very impressed with the quality and the craftsmanship of the Dalphon system. The unit functioned almost flawlessly. The only stoppage I encountered was a short cycle due to the fact that I started out with the gas system in the hot ammo setting when it was not necessary. I returned the gas block to the correct position and it continued to function great.

The finish on the upper receiver as well as the Dalphon lower receiver I tested it on was nice and dark. It was not shiny at all, and actually resembled a very desirable, early Colt finish. I have seen many different colored receivers in the past, that seemed to cover the spectrum from gray, to purple, to gloss black and this is definitely one of the best finishes I have encountered.

The necessary modifications to the bolt and the magazine were very professionally done and it is obvious that Dalphon did a lot of R&D before marketing this conversion. The bolt was opened up to accommodate the much larger base of the .50AE round and the extractor also needed to be modified. Specially modified extractors are available for your spare parts kits.

The magazine utilizes a standard 30-round magazine body with a modified follower and a built in spacer / feed ramp to accommodate the shorter cartridge. I experienced no malfunctions due to the design of the magazine. Just like the remainder of the conversion, it was very well made.

The bolt carrier and lower receiver remain original and unmodified. For some of you this statement may be the answer to a burning question you have had all along. Without a doubt, the most commonly asked question I have encountered with this conversion was not “How is the recoil?” but rather “Can you shoot it in full auto on a registered lower?” Well, yes Virginia, there is a Santa Claus, and yes, now you can shoot the massive .50 Action Express in full auto.

Dalphon is currently manufacturing upper receivers in 45ACP, 40S&W, 9mm, 10mm and 7.62x39. Others coming soon include 44 Mag, 440 Corbon and 357. If the quality of their .50AE upper receiver is a reflection of the quality of these others, I am sure you will be impressed.

P.O. Box 2215
Shelton, WA 98584
E-Mail: info@dalphon.com
Website: www.dalphon.com

C-More Systems
P.O. Box 1750
Manassas, VA 20108
E-Mail: headsup@cmore.com
Website: www.cmore.com

This article first appeared in Small Arms Review V4N7 (April 2001)
and was posted online on July 11, 2014


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