jgalar - NRAJOE is right, ammo is available now at reasonable prices.
Years ago we used to make our own brass for that cartridge, or rather we would just use 32-20 brass, as I recall, but seat the bullet flush or slightly below the case mouth to allow for a proper seal when the cylinder on those nagants moved forward into firing position. But, with new brass and ammo available, it's much easier and safer to shoot the correct ammo from that old revolver. HTH. Mikey.