I have a beautiful #1 in 7x57. While walking across a field to my stand, gun slung across my shoulder, I noticed the lever had a noticeable rattle. That normal? Don't care for that. Fix for it?

Some worse than others.
The lever latch does wear.
Ruger says its a factory fitted part.

Doesn't appear to have been used enough to wear.

Common to the breed. I have owned a dozen and they all did it to one extent or another.

I have a stainless/walnut No.1A in 30/30 that has the same problem. It is noisy enough to scare deer away. As of now it is still unfired. I’m assuming someone missed the sloppy fitting in quality control. I have left it unfired and will ship it back. Ruger said ship it back, I’ve just been procrastinating to do so. I’ve checked many no.1’s for this and all the others are much better fitted.
The wood on mine is nothing special so if the rifle were to be damaged in shipping I’m sure Ruger would make it right.

The very early No. Ones did not rattle. Newer issues do. They also do not always lift the breechblock all the way up, so the firing pin strikes low. On my latest Ruger, I drilled the lever, forward of the trigger guard, and inserted two pins, one on either side, and silver soldered them in place. I cut them down until the lever would just close and the block was centered on the bore. Now I have no rattle and feel good about the fit.
If one is happy with the breech block location, there are other ways to fix the loose lever issue as well. GD

Strange, mine is nice and tight. But something I'll keep an eye on..

My late brother’s 200th Year (or whatever) .270 had that. Drove him nuts. He cut a little piece of black polyethylene to fit the recess and glued it in place.

I've only hunted with it a few times, but it was definitely noticeable

That sucks. That is always when I find the little quirks that bother me about a rifle as well. Sometimes you don't see stuff like that at the range. When sneaking around like an indian in the quiet woods, that is a different story. Hopefully you can get it figured out. Maybe tighten something up, and quieten it down somehow.. I know I shoe goo my metal sling swivels and stuff like that, to make them quiet. Good luck with it blair..

My .45-70 did. I put a small bit of duct tape in the lever recess. Classy, no. Works, yes and not visible unless you look for it.

Seems like an easy fix. I'd probably be using black shoe goo, and then cuss as I did it!!!!!

I was originally going to put a dab of silicone glue in there to provide a little cushion. I put the tape in to test the idea, worked well so I just left it there. Forgot about it until I read this thread lol! Now it’s got me thinking about it again, I’d probably degrease the lever recess and put a dab of silicone in, coat the trigger guard with Pam and close it up just till it latches and let it cure. Orrrrrr just leave the tape in

Well dang....I was wrong above.

I recently got a No 1 back from SSK that I had re-barreled to 375 Flanged and the entire rifle cerakoted.

I don't know if the cerakote did it...but that lever does not make a peep. It is immobile as can be when locked up.