The AR15 Lower Spring Kit (also known as the Oops Spring Kit) includes all the small lower receiver springs needed for your AR-15 build or repair. Whether you’re replacing worn parts or keeping spares on hand, this kit ensures you’ll never get stuck mid-build.
👉 Pair this spring kit with our AR-15 Lower Parts Kits for a complete setup.
Includes the Following Springs:
- Trigger Spring
- Hammer Spring
- Disconnector Spring
- Bolt Catch Spring
- Takedown/Pivot Detent Springs ×2
- Safety Detent Spring (Ejector Spring)
- Buffer Retainer Detent Spring
- Magazine Catch/Release Spring
⚠️ Note: This kit does not include the large buffer spring. For full buffer assemblies, check out our AR-15 Buffer Kits.
Why Choose Midstate Firearms?
- Trusted source for AR-15 Parts & Accessories
- Affordable replacement kits for builders & enthusiasts
- Perfect backup for gunsmiths and range bags
sound of freedom – This was a great set up. I loved being able to customize the set up. Only issue I had was my own fault as a newb to building these. I used a heavy barrel in a slim hand guard. It makes adding attachments tough with clearances. Hoping someday to also get an AR10 from here.