If ???
Possible ?
Epoxy and a wood screw ?
I don't know.
Just simply guessing.

 

Got a picture of the crack ?

 

Need a picture.

While I think the Nylon 66 is a half step above garbage, I must admit I own several and have never heard of one cracking.

Oh and go easy on Remington. How could you possibly expect them to have parts for a rifle 45+ years out of production?

 

It's a .22 lr, I wouldn't have any hesitation about shooting it at all.

 

The vast majority of them have a crack some where. If it runs I would shoot it.

 

If it runs you can just shoot it. The receiver cover will stabilize the receiver enough to use the gun. There is a good chance that the crack will spread and new ones will appear though. I repaired a Black Diamond that was cracked all the way through on one side and most of the way on the other. I used Devcon HP250, an epoxy designed for high density polymers like Nylon. I inletted a piece of aluminum into each side to help support the repair. I've only put about 150 rounds through it since. So far so good.

 

i wont recommend shooting till its checked out as safe but ive never heard of a metal failure only the nylon stocks - that is quite common ,