Far from a firearm, a person probably will not immediately understand how the Adams Arms P3 differs so much from conventional AR-15 rifles. Yes, her equipment is richer, but she looks very similar to many others, and there are practically no conspicuous differences. For an experienced shooter, it will be enough to see the barrel and gas block. They are fundamentally different from those of standard rifles, and behind them are serious developments and technologies.
First, let's understand the traditional AR-15 operation scheme, as well as related terminology. Eugene Stoner, the creator of this rifle, decided to use the Direct Impingement gas system in his brainchild. In it, after a shot, part of the powder gases is removed from the bore and through the gas block is sent through a thin gas tube to the receiver, where it acts on the bolt group, pushing it back. After that, the exhaust gases go outside through two special holes.
Anyone who has fired an AR-15 rifle and then cleaned it knows firsthand how powder gases escape from the receiver and also pollute everything inside. Carbon deposits accumulate on the bolt carrier, which then have to be carefully scraped off. The features of the DI system usually do not cause difficulties or problems, and AR-15s with the original vapor system are more than reliable, no matter what anyone says - it’s not for nothing that their military versions are still in service in the US and other countries. However, with large shots, contamination of the bolt group by combustion products of gunpowder can still lead to delays in firing - especially if the firearm is not sufficiently lubricated.
Short stroke piston system
Despite the fact that the DI system is quite reliable, designers have always been interested in improving it. This has given rise to various interesting developments, one of which is the short stroke piston system. In it, in simple words, the powder gases do not push the bolt frame, getting inside it, but a separate gas piston, which already transmits momentum to the bolt frame. And since this gas piston is located inside the expansion chamber, which is placed outside the rifle receivers, the powder gases no longer enter the bolt carrier, which fundamentally reduces the heating of its elements during intensive shooting and pollution by the combustion products of gunpowder.
The presence of an adjustable gas block can be called another advantage of the short stroke system. Adjustable gas block allows you to customize the operation of the rifle's automation to the requirements of the owner. This possibility is extremely important, for example, when firing with a silencer, when it is necessary to reduce the pressure of gases in the system.
Adams Arms tested two similar AR-15 rifles, one of which had a classic DI gas outlet, and the second was equipped with a gas piston system. After firing 450 rounds with temperature pauses after every 90 shots, the result was interesting, although expected. The temperature of the barrel, gas block and bolt carrier was measured. And if the temperature of the barrel and the gas block was approximately the same, then the bolt group of the rifle with the DI gas system heated up almost three times stronger - up to 147 ° C (against 50 ° C for a rifle with a piston system).
Also, the expected soot on the bolt group of a rifle with a gas piston turned out to be much less - and solid carbon deposits formed on the bolt head of a rifle with a DI system were not found at all. The same can be said about the bolt handle and the receiver - there was practically no soot there. Just as important, the action group of the AR-15 piston was still in oil, but on the standard rifle, all the oil burned out, and the action group turned out to be dry.
Advantages and disadvantages
Every system has its pros and cons. What does the piston system give us? The internals are cleaner and don't get as hot, which means increased reliability. Gases do not fly in the face, but, on the contrary, are vented forward. But more parts and moving parts mean more complexity and cost. Fortunately, Adams Arms has been on the market since 2007, so it has perfected its product, and users have no problems.
Adams Arms offers both ready-made rifles and kits for converting a DI system to a short stroke system.
Rifles from Adams Arms are above average, but you can install the piston system itself on any AR-15 rifle. The cost of such a kit is at the level of another tuning; say, a good trigger mechanism. But we will get much more - a completely different rifle operation system. The kit from Adams Arms includes a bolt carrier, piston and gas block. You can make a replacement both in the workshop and on your own. According to reviews, the installation should not take more than an hour; the biggest difficulty is usually the dismantling of the old gas block.
Base model - Adams Arms P1
This is the simplest and most affordable modification of the "piston" rifle. A free-floating 16" barrel, a simple yet comfortable Magpul handguard. For resistance to corrosion and increase the resource, the barrel is subjected to a carbonitriding process. Additional accessories include an adjustable Defiance stock, a Magpul grip and a simple Bird Cage flash suppressor. The rifle is supplied without sights.
Improved model - Adams Arms P2
This variant differs from the basic P1 rifle in a richer package. A long aluminum handguard with an M-LOK interface is already installed here. The gas piston has five adjustment positions - against three in the basic version. Also, the rifle is equipped with mechanical sights.
Top model - Adams Arms P3
The main difference between the Adams Arms P3 rifle is the barrel from PROOF Research, made of stainless steel in a carbon fiber braid. The profile of such a barrel is made thinner, removing excess metal. The barrel blank is then wrapped in high-strength carbon fiber. This material is used in the aerospace industry, but for firearms applications, the fiber is additionally impregnated with a proprietary matrix resin. The barrel twist of the P3 rifle is 1:7", so even heavy match bullets will not be a problem for him. And the .223 Wylde standard hybrid chamber will allow the use of both civilian .223 Remington and military 5.56 × 45 cartridges. The muzzle brake compensator Jet Comp is mounted on the barrel. It does a pretty good job of picking up recoil and toss. If desired, it can be replaced, for example, with a sound moderator.
The main advantage of the Adams Arms P3 is, of course, the barrel used. However, there are other bonuses as well. Pleasant additions will be a double-sided enlarged cocking handle and a double-sided safety. They facilitate the manipulation of firearms, make them more comfortable and confident.
Despite the fact that “piston” rifles get less dirty, you still have to clean them. And here, a nickel-plated shutter will come in handy. Cleaning it is much easier - sometimes just wiping is enough. Plus, nickel plating significantly reduces friction, which means that the operation of the rifle will become even more reliable.
The P3's trigger mechanism is also not quite ordinary - instead of a cheap-angry army-type descent, a CMC Triggers trigger with a flat trigger is installed here. This descent is pleasant enough to work with, so it is unlikely that you will want to change it. The long handguard with M-LOK interface is equipped with a Picatinny rail along the entire length - this is enough to install any necessary equipment. Mechanical sights are immediately installed on the bar, which are never superfluous.
The AR-15 family of rifles from Adams Arms is very different from others. The "piston" system has enough advantages and has a large number of fans around the world. We hope this article was useful to you and when you see such a rifle in the store, you will definitely know the difference between this model and many others.