Keep Your Bolt Running Right

Replacing mainspring retaining pin with bolt block.
Replacing mainspring retaining pin with bolt block.

Next is taking the firing pin assembly apart. This can be done without the tool but is really not much fun and can be dangerous to the eyes should the spring get away from you. This is a good time to mention that any time you are taking apart a compressed spring (with or without a tool) eye protection is a must.

The mainspring tool is a tube that the firing pin assembly fits into and uses a thumbscrew to compress the spring and push the block out the top of the shroud far enough to push out the retaining pin. The spring and firing pin remain trapped in the tube so they can’t be launched. Once the retaining pin is removed, the mainspring tension can be removed by loosening the thumbscrew and the spring and firing pin come out for cleaning. Again, mine was wet with residual solvent, which could cause a build up because of grit and fouling sticking to it. Worse, if there were no solvents on the pin, it could become victim to rust and pitting.

Once the retaining pin is exposed it can be removed by placing the bolt on the bench block and tapped out with a small hammer and punch. When replacing the pin, if it is a little tight, a brass hammer will keep from deforming the pin due to the hammering. A good wiping and a light coat of lube was all my firing pin assembly needed. Don’t leave the parts wet with lube; use only a light coat. We want to inhibit corrosion not collect grit and dirt. The tool really shines putting the firing pin assembly back together. God didn’t give a man enough hands to compress the spring, line up the holes, and get the pin back in. The tool does all the holding, you just put in the pin.

Firing pin mainspring retaining pin.
Firing pin mainspring retaining pin.

The final part that needs attention — and can cause problems if it sticks from fouling — is the ejector. This is the little spring-loaded plunger that protrudes from the bolt face. It is retained with a small pin and if it sticks down flush with the face of the bolt it will not push on the base of the fired case and throw the brass clear of the rifle. I have had this happen and it is a pain. The difference between this spring-loaded part and the firing pin mainspring is its size. It is a lot harder to find when launched to parts unknown around the shop. The Sinclair ejector spring tool traps the plunger and spring and holds it until the retaining pin is punched out. It can then be controlled while releasing the spring tension and all the parts remain on the bench. It can then be wiped and lubed and the hole it lives in cleaned with a Q-Tip. It doesn’t take much fouling to freeze this part in the cave.

The ejector spring tool fits over the end of the bolt and is tightened against the spring by pushing it in and turning it to lock it on the bolt lugs. It comes with two bolt face fittings for small bolts like .223 and larger bolt faces from .308 to the magnums. This is invaluable for replacing, maintaining, or shortening the ejector spring. Once the spring is trapped the bolt is placed on the bench block and the pin tapped out. The extractor can then be cleaned in the bolt. There is no reason to remove the extractor unless it is broken, which doesn’t happen very often on a Remington bolt.

After everything is cleaned and lubed it goes back together quickly and the rifle is ready for the next mission. Many believe bolt maintenance can be neglected for a very long time, as they will function for years before any problem arises and are quite reliable. I can’t abide by that philosophy. The bolt should be taken apart periodically and cleaned and also inspected for any upcoming problems that would be better addressed prior to that hunt of a lifetime or important mission. Sinclair’s bolt tools make the job quick and painless.

Recommended Resources for Gunsmithing


Gunsmithing with Patrick SweeneyGunsmithing with Patrick Sweeney CD

Gunsmithing Semi-Automatic Pistols CD

Gunsmithing the AR-15

Shop All Gunsmithing Books/CDs »


Please enter your comment!
Please enter your name here

This site uses Akismet to reduce spam. Learn how your comment data is processed.