In the European space, there are several manufacturers offering AR15 rifles. First Oberland Arms as one of the first, then followed by Schmeisser, Sig Sauer, and Dynamic Arms Research - just to name a few. The weapons come in various designs depending on the manufacturer. Some custom models are also offered, but generally you have to work with the parts the manufacturer offers, and are limited to a few parts, especially the basic components like the Upper and Lower.

Horner Arms from Heubach, under the leadership of Matthias Horner, specializes in building AR15 weapons themselves and importing sought-after parts from the United States.

Today in the first part - the second part is HERE - we give you an insight into the assembly and construction of an AR15 - from A like Trigger to Z like Feeder. Know your gun!

But to whet your appetite, here's a video of the finished weapon:

The AR15 is essentially divided into Handguard, Buttstock, Upper, and Lower.

First, we show you the lower part of the rifle (graphic: click to enlarge).

The Lower is the home of the trigger and other controls. Additionally, the buffer tube with the buttstock and the upper are attached to it - all parts positioned on top. The choice of Lower fell on Aero Precision. The company is based in the USA and produces excellent AR components - and that at incredibly affordable prices with first-class workmanship and quality. The following components are installed in the Lower:

• Trigger group

The trigger group consists of trigger, trigger spring, hammer, hammer spring, disconnector, disconnector spring, and the corresponding hammer and trigger pins for attachment in the Lower.

The trigger was chosen to be the Geissele Super Semi Automatic Trigger (SSA), already introduced here.

• Safety

The safety of an AR is typically only found on the left side of the rifle. It consists of the lever, the middle section, and a spring with a bolt, held by the grip frame. For the custom build, we chose a Battle Arms Development Bad-Ass Ambi Safety Selector, which is operable from both sides. With this model, the sizes of the levers are selectable, allowing for a short lever on the left side for right-hand use, and a long lever for the right side, or vice versa. This safety selector needs to be rotated 90° to switch from Safe to Fire and back.

• Bolt catch lever

The standard bolt catch lever consists of the bolt catch, roll pin, spring, and plunger. This can only be operated from the left side and requires a right-handed shooter to switch hands to hold the bolt back. To counteract this, and make the bolt catch operable from both sides, a Phase V EBR V2 extended bolt release has been installed. This allows for operation from the left side (like the original) and additionally, with the L-shape, it enables operation by the trigger finger in the front trigger area. The Phase V has the advantage over the more well-known Magpul BAD Lever in that it doesn't screw a component onto the existing standard bolt catch lever, but replaces the entire part.

• Magazine release

The magazine release consists of the release button, a spring, and the magazine catch lever. The button is usually operated from the right side and has been extended here with a Norgeon Ambi Catch, replacing the standard magazine catch lever. This allows for the magazine to be released from the left side as well.

• Trigger Guard Assembly

This is the part that closes around the trigger guard. It is held at the front and back by pins. A BCM Triggerguard made of Polymer was used.

• Take Down Pin

The Take Down Pin is the part that holds the Upper and Lower together at the back. It is held in place by a spring and a small pin. Removing this pin allows for the Upper to be flipped up and the bolt carrier group to be removed.

• Pivot Pin

The counterpart to the Take Down Pin is located in the front area of the Lowers. It is also held by a small pin with a spring and allows for complete separation of the Upper from the Lower when it AND the Take Down Pin are removed.

The Lower also directly attaches the pistol grip and buffer tube.

The pistol grip includes, as mentioned, the spring and pins for the safety. It is fastened to the Lower with a screw. For this weapon, a BCM Gunfighter Grip Mod 1 was chosen. In contrast to many available grips, it is less angled, providing a more comfortable grip. It also has a compartment for storing small parts and is very grippy due to its texturing.

The buffer tube is screwed into the Lower. The castle nut holds everything together, while the receiver end plate secures the tube from twisting. Inside the tube are the large spring and the buffer assembly that moves the bolt carrier group. The assembly is held at the back by the buffer retention spring with pin. The tube with its components and the extension ring are standard MilSpec parts that are always in stock at Horner Arms. The Endplate is also from BCM and has a QD Swivel mount on the underside.

On the buffer tube - as shown in the graphic (click to enlarge) - a collapsible stock is attached to modern M4 and AR15 variants. Here you'll find the Mission First Battlelink Minimalist Stock, one of the lightest and most adjustable collapsible stocks on the market. This stock omits the usual reinforcement in the lower area and has a hook-like appearance. It is made of high-strength material, and the shoulder area is padded with a rubber plate. Additionally, there is a QD swivel attachment point for a sling in front of the adjustment knob. The stock fits securely and doesn't wobble at all.

With all these parts, you have what is called a complete Lower - a "filled" Lower with buffer tube and stock. This can also be purchased ready-made and is completely freely available in Germany.

If you want to know what happens next, here you can see everything laid out.

Coming soon on SPARTANAT: the