If you are planning to buy an AR15 for home security or your shooting practice, you have come to the right place. In this post, we will discuss the different types of the weapon to help you make the right choice. The upper and lower receivers are the two main parts of the firearm in the AR 15 models.
In this two-piece firearm, the upper receiver contains the bolt and the barrel that helps carry the bullet. The lower receiver, on the other hand, has the firing mechanism and the magazine. The upper receiver directly impacts the accuracy of the AR 15 weapon. Plus, you can convert a long-range weapon into close-quality combat (CQC) by changing the upper receiver.
Federally licensed firearms dealers need to sell the lower receivers with a serial number. You can combine various upper receivers with a lower and improve the weapon performance without any extra paperwork.
Different Types of AR15 Upper Receivers
There are two kinds of upper receivers by design:
- Flat top upper receivers
- Carry-handle upper receivers
The flat-top upper receivers have a Picatinny rail, and you get a fixed rear sight assembly of the weapon. The carry handle, on the other hand, is an actual carry handle you can find on top of the rear end that has a built-in rear sight.
A1, A2, A3, and A4 are the different models of upper receiver you will find when looking for an AR15 weapon. But, first, you should know that the A1 and A2 feature a built-in carry handle while the A3 and A4 use more modern picatinny rails for ease of attaching optics.
Forward Assist Button
The forward assist button can make a major difference that you should know before you choose an upper receiver. You may find this forward assist button on your AR-15 rifle, and it plays a vital role in the gun. The military-grade M4 and M16 rifles have these buttons to ensure that the bolt is fully seated as soon as you press this button.
Upper Receiver Construction
You will find upper receivers made of various metals, but manufacturers commonly use aluminum for manufacturing AR15. Following are the types of upper receivers according to their construction.
These differences depend on their construction methods, and we will discuss the details below.
Forged Upper Receivers
The forged receivers have the ideal grain structure and orientation, which helps develop the right hardness and specific weights in these upper receivers. However, these forged upper receivers are heavier in weight as manufacturers make them by forging (hammering) and completing them by the CNC lathe.
Billet Upper Receivers
The billet upper receivers require a solid metal piece with CNC until it forms a proper shape. These billets have similar properties to the forged upper receivers but have lower density and are lighter in weight. However, these billet upper receivers are not as durable as the forged ones.
Cast Upper Receivers
Cast metal is lightweight and also offers the least amount of durability amongst all other options. These cast upper receivers require pouring liquid metal to get their shape (called die-casting). The constructors use some CNC metal to finish the work.
Stripped and Complete Uppers
A stripped upper receiver is just the upper part and is only a solid piece of metal. The complete uppers include a few extra parts, which eliminates the need to make any other purchases. However, you need to invest in an upper parts kit that includes a dust cover and a forward assist. You can easily add these parts to the main assembly of the upper receiver and complete it.
Now, let’s look at the different types of AR15 upper receivers you can buy.
The A-1 Receivers
The A-1 Upper receivers are the original weapon designs from the 1960s, and the Vietnam soldiers first used these upper receivers on their M-16A1 rifles. These A-1 receivers have a light profile barrel and a forward assist for the users with a fixed carry handle. You can also find a flip rear sight that helps shooters adjust the windage but not the elevation of the weapon. These upper receivers have short sight and long sight apertures. This way, you can get a 1:2 twist rate and accurate firing within 450 yards.
The A-2 Upper Receivers
The A-2, introduced in the 1980s, has the fixed handle forward assist as the A-1 upper receiver. However, this upper receiver provides better performance since it has a more adjustable elevation (up to 600 yards) and windage. It also has a heavier barrel than the previous variant. You can also find left-handed brass and rounded handguards as compared to the triangle-shaped handguard that the A1 had.
A-3 Upper Receivers
The A-3 upper receivers have a flat top configuration with a detachable handle for carrying. You can either equip the A-3 upper receivers with a Picatinny or Weaver rail that serves as a mounting platform if you need to add scopes or other accessories. The A3 receivers also have forward assist with rifle cuts in the freed ramp. Some of the A-3 models also have a high-rise configuration with an extended base for a higher scope positioning.
A-4 Upper Receivers
The A3 and A4 upper receivers are quite similar. But there is one difference, which is the A4 has M4-style ramps, which complement the barrel in the design.
Understanding the difference between AR15 upper receiver types not only helps know the different variations the receivers have gone through, but it also helps learn more about the AR-15 weapon too. Adding the right upper receiver to your gun will let you improve your aim, boost firepower and enhance the overall performance of your rifles. So, make sure that you choose the right upper receiver according to its design and construction, and you will surely have a better AR-15 shooting experience. Also, make sure to choose a credible firearms dealer and discuss your requirements when buying an AR15 upper receiver.