Sig Classic Pistol Function Checks

Sig Classic Pistol

Sig P229


The Sig Classic Pistol Function Checks are used to verify the working order of an unloaded firearm and are important to complete after doing any work on a pistol or troubleshooting an issue. However, safety is the first and most important priority when performing any function check on a firearm.


All firearm safety rules apply when doing safety checks. However, before beginning make sure that all ammunition has been removed from the area, visually and physically inspect the firearm is unloaded (then check again) and finally always make sure that the firearm is pointed in a safe direction when performing any safety check.


Sig Classic Pistol Function Checks – combined function testing


The following magazine, frame and slide can be check at the same time. If applicable, the magazine should be inspected as previously described for serviceability. 


  1. Insert the unloaded magazine into the firearm and ensure that it locks into place.
  2. The slide is then moved to the rear while the empty magazine is in place. The slide should lock to the rear.
  3. The magazine catch is depressed and the magazine should fall free from the firearm of its own weight. This verifies the correct relationship of the magazine, magazine catch, and action.
  4. Press the slide catch lever, “the slide should spring forward.
  5. On double action guns or DAK trigger guns, the hammer should follow the side forward. On DA/SA or single action guns, the hammer should remain in the cocked position.
  6. On Single action or DA/SA guns, forward pressure should be exerted on the spur of the hammer The hammer should remain cocked. This verifies the hammer/sear engagement functions properly. 
  7. To check the double action function of the hammer on double -action or DA/SA guns, press the trigger to the rear, the hammer should cock and release for every press of the trigger.
  8. The disconnector is tested by pulling the trigger and holding it to the rear while retracting and re eas ng the slide, this proves that the trigger has to be reset to fire the next cartridge. The side is then pulled back slightly out of battery, and the trigger is pressed, when the trigger s pressed the hammer should not move if the disconnector is working properly.
  9. on single action guns, the single action trigger function is tested by cycling the slide which cocks the hammer, then pressing the trigger to release the hammer.
  10. On all pistols except those with the DAK trigger and early production P220, the trigger should be held to the rear and the hammer pushed forward to verify that the hammer reset spring pushes the hammer rearward.


The ultimate function test is to live fire the pistol.


Sig Classic Pistol Function Checks – Slide Specific Checks


After disassembling and reassembling any classic line slide a function check should be performed on the extractor, firing pin and firing pin safety.


  1. Using a punch, pull outward on the extractor. Spring tension pulling the extractor back towards the center of the breech face should be felt.
  2. Press in on the rear of the firing pin, it should not extend out through the breach face.
  3. While pressing in on the firing pin, press in on the firing pin safety lock. This should allow the firing pin to extend through the breach face of the slide. Release the firing pin safety lock and as the firing pin is allowed to return to the rear, the safety lock should lock back into place preventing the firing pin from coming through the breach face.


Inspection of the slide and slide components should be completed while you have the slide disassembled.


  1. Inspect the side for cracks and deformities. Wear of the finish is to expected and will vary depending on use and handling.
  2. Inspect the barrel for bulges. cracks and deforming and ensure the lands and grooves are intact. 
  3. Inspect the firing pin for chips and cracks, ensure that the firing pin moves freely in the firing pin well. 
  4. Inspect the extractor to ensure the extractor hook is in good working order and has not been chipped or broken. All surfaces should be inspected for corrosion and should be lubricated prior to reassembly.