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Looking for a load map for .308; RE-15 & Sierra MK MOLY

fnbrowning

Sergeant
Full Member
Minuteman
Feb 16, 2007
244
17
St. Louis Missouri
In .308, I’ve been shooting the 175gr SMK Moly out of a 20” Armalite AR10. After years of faithful service, I’m having the upper rebarreled with a JP Rifles Supermatch barrel. Of course, I will have to start over with my load testing this summer. I had a great load for the Armalite Chrome/CM barrel, but it took a while, because load data is not readily available for the different pressure curve of moly coated bullets.

Oh, I know there's a program out there that does a great job, but please understand I just need one cartridge/powder/bullet. If your software does Sierra Matchking Moly bullets, it would be ever so helpful to see just one powder, Reloder-15. I understand we're not supposed to use the name of the program with a load request, so I'm hoping someone can read between the lines here, and email me an Excel file? ;)

So if you feel inclined, here are the inputs for that barrel.
Cartridge: .308 (7.62mm NATO)
Bullet: 175gr Sierra Matchking Moly Sierra #2275M
Usable Case Capacity: Winchester Average Grains ~57.32
Cartridge O.A.L = 2.800
Barrel Length = 22" length ● 1:10 twist
Just one powder, Reloder-15

Thank you for your consideration request.
 
Sounds like you did it right the first time, you need to do the same thing for the new barrel. Use the knowledge you gained in developing the first load to cut out the unnecessary minuita that may have existed while you were learning.
Is there really a computer smart enough to tell you the exact load you should use with a rifle without load development? I wish, but I do love burning powder anyway.
 
Why is it that some people disparage computer data simulations so? You ask for a data set, and they immediately assume that you are demanding a "computer (program) smart enough to tell you the exact load" etc. Hey, it's just a data set. Doesn't mean the solution, only that the more data you have, the clearer the road you are traveling. :)

Anyway, thank you to the member that sent me the (redacted)load Excel file. One look at the pressure data and I've found I was far too conservative; I have more pressure headroom to work with than I originally thought years back.

That's why you can never have too much data.
 
OCW handles this also, as you load up to your desired max and the next increment that takes you over that max. If still no pressure signs, you can go up step by step. One step will not go from no pressure signs to dangerous.