Required parts for building a rifle
These are the most required parts :-
- AR-15 lower receiver.
- AR-15 upper receiver.
- Lower receiver parts kit.
- Upper receiver parts kit.
- Lower receiver extension (aka: the buffer tube).
- Buffer.
- Buffer spring.
- Barrel & gas block/gas system (a carbine length gas system would be typical for this build).
- Handguards (length will depend on what length gas system you chose on your barrel: carbine, mid-length, or rifle).
- Bolt carrier group (carrier, bolt, firing pin, cam, extractor, ejector and spring).
- Collapsible (or fixed, if you prefer) buttstock.
- At least one magazine (be sure to check your state laws for magazine capacity limits).