rifle newb trying to work up a functional/semi-economical load to get me started. Not knowing too much about rifle loading in general, Here's what I'm using:
LC pre-processed brass
Hornady 55 grain FMJBT
Winchester small rifle primers
Lee die set
I'm loading for 2 guns (wife and mine) both chrome lined both 5.56 chamber. I was wondering if you guys might be able to let me know where an acceptably accurate load might generally lie with these components w/ my particular barrels.
18" and 16"
Some data I've collected on a cool, drizzly day ~67 degrees sea level (16" rifle 1/7 twist):
25 gr. 2616 fps
25.5 gr. 2674 fps
26 gr. 2771 fps
26.2 gr. 2801 fps
27.1 gr. 2899 fps
18" rifle 1/8 twist
25 gr. 2685 fps
25.5 gr. 2785 fps
26 gr. 2899 fps
26.2 gr. 2925 fps
27.1 gr. 3010 fps
I had powder gathering in my powder die. . . it didn't seem right to me so I took some sandpaper, twisted it up and sanded the inside of the powder die a bit to smooth it out. Now, I'm getting much more consistent powder throws. My OAL target is 2.235" but I noticed that the bullets themselves vary a lot in length, and my cartridges w/ the lee dies vary up to .01" sometimes. My extreme spreads average around 60 FPS. Is this normal? I don't have one of those comparator do-hickeys.
26.2 fps was the listed max load, so I approached it slowly and then went for ~27 grains (based on others here loading to 27.5) to see what the velocities would be and checked primers for danger signs. It was a cool day, and the velocities were not out of control, so I went ahead and tested. Primers seemed to all be ok. I was hoping for ~3100 ish but didn't get it. I don't even know what power factor I need to have for the game. Given these velocities, where's my range to focus on for a little bit of accuracy testing? What I'd really like to do is just make a bucket load of ammo and work on skills since I don't have any
at 27 grains, the cases were getting pretty much filled all the way up w/ just a little bit of space left it seems.
With these barrel twist rates, i'd assume my more accurate loads would be heavier bullets, but this is where I'm starting from and I'd like to see if I can get a functional load w/ the 55 grain and cheaper powder to build some skills before moving up to 75 or 77 grain bullets.
Edited by chunger, 26 November 2007 - 03:20 AM.