Hello, I have a Ruger M77 Mark II in .458 Lott. My problem is that when I close the bolt there is a loud "squeak" that I have not been able to identify. If closed real real slow, no problem. I have oiled, cleaned, etc and it does not appear to be external "metal-on-metal".

When I apply downward pressure on the rear of the fire pin assembly (where the word "SAFE" appears), the squeak dissapears regardless of how fast the bold is turned.

It's driving me nuts, any ideas? Thanks in advance.

If you hold the trigger back as you lower the bolt handle does this squeak shill persist?

There are threads that rotate inside the bolt. You can see them if you remove the firing pin. Are they lubricated?

Lubricants made with a synthetic base stock are good for this.

Are your bolt lugs lubricated?

D, No, when the trigger is held back it does not squeak. What do you think?

Savage, I didn't remove the firing pin from the bolt assembly, I'll check.

Put a dab of grease on the bolt shroud threads (where the shroud screws into the rear of the bolt body).

Hello,
Would suggest that you not put oil anywhere on the bolt or action per se, but rather a good quality grease w/ extreme temperature ranges. There are numerous commercial brands on the market, but many use disc brake grease, synthetic, found in auto parts stores. Economical and has very broad range for temps. Place on back side of bolt lugs, both ways in action, cam surface on rear of action/bolt area, and yes in your case, on the threads of the striker/bolt shroud. Sparingly!! None to be on bolt face and that is one reason oil should be avoided for it is easy to get in the wrong place.

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dsiteman

Don't use grease or oil at all. Clean everything down as much as possible and then heat it up with your hairdryer or put the parts in the oven on a cookie sheet to get them up to about 150 degrees F, and then put some microlon gun juice or Bore Tech tef dri on all the bearing surfaces. I have done most all of my rifles this way and they work smooth and quiet and don't attract/hold dust, dirt etc.

Having said that, D Humbarger is right a little lube should kill your squeak.