Customizing an AR15 into a Side Charging Piston Operated Rifle

The “Before” pic

U.S.A.-( Last year, Palmetto State Armory sent me one of their PSA-15 MOE Freedom rifles chambered in 5.56, and between my initial testing and a few range sessions I found this rifle to be an exceptional bargain. However, ARs have a curse on them: They simply beg to be modified.

This goes with their ease of use and their design being “open source” at this point. The AR-pattern rifle is like the Chevy small block of black rifles.

I decided to turn my good rifle into a great one. There were no problems with the PSA-15 MOE, but I wanted to experiment with a few enhancements.

The first item on my “to do list” for the PSA-15 was to convert from direct impingement to a short-stroke piston system. I went with the Osprey Defense 416 piston kit. This particular kit is intended for a carbine length gas system and will accommodate 11.5″ -16″ barrels up to 1.00″ in diameter. The company literature claims that installation takes 5 minutes. As experienced as I am with building ARs and M16s, I found it took a bit longer than that. Closer to 20 minutes.

Osprey Defense 416 piston kit

One thing to ponder if you are considering this for an existing rifle is that the piston system is not friendly with most hand guards beyond the original M4 types or MagPul MOE like I had on the PSA rifle. Sometimes it’s the piston chamber that attaches to the gas block and sometimes it has to do with the barrel nut in question. Most often, these will require a different operating rod. A few companies now make rails that will work but check with your hand guard manufacturer beforehand.

With the upper receiver separated from the lower, you will need to remove the hand guards and then drive out the roll pin that holds the gas tube in place on the gas block. If you shoot your rifle a lot, you will need to clean the hole in the gas block. The piston chamber is pinned to the gas block and then you need to install the piston and operating rod.

This is easily the most time-consuming part of the conversion. The operating rod must be rotated flat-side-up and is secured to the piston via a retaining clip. Fitting is very tight, and I suspect my lack of familiarity with the piston system compared to DI rifles is why it took me a bit longer than the company claimed.

PSA-15 MOE Improved

Included in the kit is a new bolt carrier and I used the rifle’s existing bolt after I removed the gas rings. With this installed, I replaced the handguards and took off to the range.

Osprey’s piston kit is said to increase reliability, keep the rifle cooler and cleaner and will function in all adverse conditions: dirty, wet, cold, full-auto, semi-auto, suppressed, or unsuppressed and the rifle can now go for 10,000+ rounds without cleaning or failure.

I didn’t have 10,000 rounds to spare on this one but after 400-500 I could not believe how clean it remained. All that carbon was no longer blowing back into my receiver.

If you are interested in an Osprey Defense piston kit, they are now owned by Franklin Armory of Minden, Nevada. The kits can be purchased here or from retailers like Brownells. MSRP is around $300.

With that complete, I turned to my second order of business. I wanted a side-charger.

The debate for and against side chargers is not as heated as the direct impingement vs. piston battle, but some folks don’t seem to get it. While I do not have one on every rifle, I do have a few. I saw no reason to swap out my upper receiver, so I went with a Hard Charger conversion from Devil Dog Concepts.

Devil Dog Concepts Hard Charger

It simply mounts to your rail and you replace your existing charging handle with the one provided by DDC. This truly took about three minutes to install. Since I was not using optics, I went with the standard version. They make a “Tactical” version that uses the third rail from the rear to get out of the way of most scope mounting systems.

In addition to helping eliminate excessive gas from a suppressor, the side charging conversion gives you a non-reciprocating left-side charging handle to allow you to clear malfunctions easier and some shooters prefer the placement of the charging handle on the side as opposed to the rear. Back to the range with about 200 more rounds, I tried it out and again, I suffered no malfunctions of any type.

Devil Dog Concepts was founded by a Marine, hence the name, and a lot of former Active Duty guys work in the shop, using their real-world experience to make better gear.

The price on the Hard Chargers has come way down in recent years and they can be had for as low as $126. You can find more information here.

One last thing I wanted to change was the flash hider.

I have nothing against the A2 birdcage and think it is great for what it brings to the table. However, many of my guns end up as testing platforms for gear such as optics and silencers. I wanted a muzzle device that would perform well, but could be removed and reinstalled quickly. This way I could use other mounting systems, etc.

Triumvir by Franklin Armory

I installed a neat flash hider that I have grown fond of called the Triumvir by Franklin Armory. It allows for a reduced dust signature when shooting prone and acts as a compensator to keep you on target. It propels the muzzle report forward and makes shooting unsuppressed rather enjoyable.

Some may think that this is pouring a lot of money into a budget-priced rifle. Maybe it is and maybe a bit of time, money and effort could be saved by starting a rifle build with these components or even buying a factory-made rifle with these features. However,  as the AR begs for customization, you can have a fully functioning rifle and add parts like this as you go.

PSA-15 MOE Improved

At the end of the day, I had a spare bolt carrier, gas tube, A2 flash hider and charging handle.

That’s enough to get rolling on another build!

About Mike Searson

Mike Searson
Mike Searson

Mike Searson’s career as a shooter began as a Marine Rifleman at age 17. He has worked in the firearms industry his entire adult life as a Gunsmith, Ballistician, Consultant, Salesman, Author and was first certified to teach firearms safety in 1989.

Mike has written over 2000 articles for a number of magazines, websites and newsletters including Blade, RECOIL, OFF-GRID, Tactical Officer, SWAT, Tactical World, Gun Digest, and the US Concealed Carry Association as well as AmmoLand Shooting Sports News.

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