LYMAN 311291--A little help, please

[lathesmith]

Hello all,
I need to make a Star die for the Lyman 311291, and I don't have access to either a sample or mold. I need the center-to-center lube groove measurements. This slug appears to have 3 lube grooves. Some help and clarification would be greatly appreciated.
Thanks,
lathesmith

[AnthonyB]

I wouldn't trust my measurements but would be happy to send a sample. PM me and I'll get it out.
Tony

[Rockydog]

Lathesmith, I have a 311291. It has what I would call 2 lube grooves and a crimp groove. (Although I usually lightly crimp on the 3rd band just under that groove.) I've only got a caliper to measure with right now. Near as I can see the first groove is .225 from the base of the checked bullet to the center of the groove. The second groove appears to be .125 center to center from the first. The center of the third groove (what I'd call a crimp groove) appears to be .10 Center to center from the second groove. Bottom and 2nd Driving bands themselves measure .10, third band .075. Top driving band back to .10. I'm not staking my life on these measurements the eyes are getting a little fuzzy once in a while. But I hope this helps. RD

[RayinNH]

Lathesmith 311291 has two lube grooves and a crimp groove. The gas check shank is fairly long so you end up with about a half lube groove above the gas check. To answer the question you asked though my boolit's lube grooves are .135 center to center...Ray

[lathesmith]

That's just the info I needed guys, thanks. When setting up a Star die, especially for a slug that has 2-3 lube grooves, getting close is good enough; in this case, 3 rows of holes, spaced .125-130 apart, will do nicely, and will allow a user to lube the space above the gas check, which some guys like to do.

Thanks again guys, and good shooting...

lathesmith