Mr. Single Shot's book of rifle plans

[Grizzly Adams]

Machining the concave support shoulders on a lathe. Notice the heavy vibrations from the interrupted cut!

Machining the convex support shoulders.

I am wondering if there is another way to do the support shoulders not requiring a faceplate setup?

Grind the radius ?

Grizz

 

[fat tony]

Grind the radius ?

Grizz

From memory & some net browsing, he showed pics of an ersatz grinding set up in a large old school floor drill press with oversized table which almost certainly had low speed(s) available. If a tribesman in Waziristan sitting on the deck in front of a 6" bench vise can turn out lmg parts, the C. F.Chicopee surely must be in closer reach. The problem would be getting equal surface finish & equal bearing on the faces. Without scaling it up, I think they reccomend no bigger than .22 Hornet or .25/20. Maybe something like .32/20?