Please help ID a US made 7.62x51mm cartridge. Brass case, “RA + 59” headstamp, red tipped projectile. There is an extra cannelure above the one at the case mouth. I am assuming that this is an “M-62 (overhead fire)” tracer cartridge, but the extra cannelure has me stumped. I have not seen a picture of this cartridge to verify that it is not a reload, only received a written description of it.