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The SPAS 12 Project LLC 2020

Special thanks to contributors Alexander H.,  Cole C.,  Zach G., Alex G., Paul S., Craige H., Neil Z., Rick J. Mark M., Tom S., Ben O., Taylor S., Joseph D., Anthony D., Steve P. and David B.

Receiver Buffer Install

(Fixed Stock)

Special thanks to Cole C. for providing this write-up!

Tools Needed

- Phillips #1 Screwdriver


- 1/4" or 3/8" Drive Ratchet


- 10-Inch Extension - 10mm Socket (Yes. We are using a Metric Socket. The SPAS 12 is made in Italy. Metric fittings are used.)


- Engineering Hammer / Mallet with thermoplastic, Polyurethane, or Nylon tip for soft metal applications (These are impact cushioned and non-marking and good for a delicate aluminum receiver)

Step 1

Remove the buttplate of the SPAS-12 stock using the Phillips #1 Screwdriver. This will give you access to the internal portion of the stock and the stock mounting bolt that attaches the stock to the receiver.

STEP 2 is optional. If you want more space to work with your ratchet and extension, removing the internal stock brace that is recessed slightly inside the stock. Use the Phillips #1 Screwdriver to remove the top and bottom Phillips head screws that hold the internal stock brace in place and remove it from the stock.

- Assemble your 1/4 or 3/8 ratchet with 10 inch extension and 10mm Socket

- LOOK inside the stock assembly and locate the black oxide coated 10mm bolt that holds the stock to the SPAS-12's receiver (You may need a flash light to locate the bolt, but it is located towards the bottom of the stock)

- Remove this bolt using the ratchet, extension, and 10mm Socket (You will rotate the bolt to the left (Counter-Clockwise) to remove it)

Step 2

With the new receiver recoil buffer on place, you are ready to re-assemble.Re-assembly is in reverse order.Make sure the SPAS-12 Project Receiver Recoil Buffer has snapped firmly into place.Attach the trigger plate and gently punch the two pins in place.Next, re-assemble the stock by attaching the stock to the receiver with the mounting bolt. Tighten the mounting bolt clockwise (to the right) using the ratchet, extension, and 10mm socket. Complete the installation by attaching the internal stock brace if necessary and finally, the stock buttplate/end cap using the Phillips #1 screwdriver.

Step 5

Step 3

Use a Pin Punch and the Engineer's Hammer to GENTLY hammer out the two trigger pins. GENTLY pull the trigger plate assembly out of the bottom of the receiver. This assembly is very easy to remove once both pins have been punched out from the receiver.

With the trigger plate removed, now is a good time to clean up the inside of your receiver.I elected to use non-chlorinated brake parts cleaner to hose out the debris and residue. I then sprayed in Amsoil Metal Protector to oil and lubricate the receiver internals. 
Locate the receiver buffer towards the upper rear of the SPAS-12's receiver.From the outside of the back of the receiver, locate the small, circular hole in the receiver that retains the factory receiver recoil buffer. Use an Engineer's Hammer and Punch. Gently punch out the receiver recoil buffer so that it falls off inside the receiver. Check the retaining hole for any debris and remove the debris if necessary. Press in the new receiver recoil buffer from SPAS-12 Project.

Step 4