Differentiating an M1A Rifle from an M14 Rifle
The first thing that you might notice about these two rifles is the striking similarity in appearance. It should be similar because they are essentially the same in almost every feature except that one rifle is used by the army and the other one can be purchased at any reputed gun store.
Like the saying goes, the differences are only skin deep. For beginners, the receivers of the M14 are manufactured using what is known as the drop-forge technique. M1A on the other hand uses an investment cast receiver and may be comprised of a mixture of genuine United States GI military specification parts along with case replica parts, or simply all United States GI parts or even mostly investment cast parts along with smaller military specification parts. The sound created by the two receivers is different and any rifle audiophile can immediately differentiate the two by simply listening to their sound upon discharge.
The selector switch of M1As manufactured post 1990 are different from the ones on the M14. The M14 uses a walnut stock similar to the M21 that is height adjustable. Additionally, the 7.62mm caliber design was also dropped after the 1990 model of the M1A. M1As work only off 7.62x50mm NATO ammunition and not on anything else.
The bayonet lug has been removed from the newer M1A models. This was following the Assaults Weapons Ban of 1994 that prohibited the use of bayonet lugs on civilian weaponry. However, there is a workaround that allows owners to attached a bayonet lug to their M1As since the flash suppressor on the M1As are all identical.
When it comes to disassembly as well, there are minor differences between the two. With the M14, you can simply remove the connector and the operating rod slides out whereas the M1A uses a technique commonly known as “twist and pray” to remove the operating rod.
The M1A is strictly a semi automatic rifle. There is no way that it can be made to operate in a full automatic mode. The M14, on the other hand, is a selective fire military weapon. This translates into it being able to operate in selective automatic fire mode. The military initially hadthe selector switch to operate the M14 in full auto but eventually had it removed to a functionless knob since most of the soldiers were habitually leaving the selector to auto under all conditions. The M14 was infamous for not being very controllable in the auto mode and hence it was decided to drop the switch after a while. Thus, this is the reason why almost 90% of the M14s out there are forcibly semi auto with no option to switch.
The other big difference between the two weapons is the inflated price tag. The M14 is at least $14,000 dearer than the M1A. The high cost is attributed to the costlier fabrication process and the use of costlier military grade materials while making it. Hence, you need to be cautious and use discretion while handling the M14, especially if it is in the auto mode.