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Posted: 4/12/2009 2:13:36 PM EDT
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Seems the links to Ammo Oracle are dead.
Almost done with my first build (first AR). I currently reload. Want to select bullet brand and wieght, so i can get started reloading, and have some ammo for when I get the barrel on my gun. Interested in long range match type shooting, and staying close as I can to actual military rounds. I am bldg a SDM-r with barrel from CLE. 1:8 twist, 20". I do not even know how to start a search on this. Seems the Ammo Oracle had useful info when I researched this about a month ago. |
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I perfer the "old" one...........
http://www.razoreye.net/mirror/ammo-oracle/AR15_com_Ammo_Oracle_Mirror.htm Anyway, I suggest that you keep it in your favorites. Aloha, Mark |
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Indeed, the SMK 77 gr HPBT is the Mk262 projectile. That's the Sierra Matchking HPBT Cannelure #9378. It flys well out of 1:8 twists. Seats within the 2.260 mag. length limit. The cannelure is almost just window dressing, almost painted on. So, many just seat for best jump to lands and ignore the crimping operation. Go to Sierra's website. Sierra Bullets - The Bulletsmiths:
http://www.sierrabullets.com/index.cfm?section=techservice&page=xring&volume=6&iss... Find good load data there. |
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Thanks CCW,
I looked up the data on the link. I will start at the min. This brings me to another question about general reloading. The "accuracy" load in the Sierra article with the loads has the max RE15 load. I have always obtained best accuracy with max listed loads. In your opinion is the barrel wear over the starting load significant? Maybe I should practice with min loads and pull out the "max load" mag when I my shooting skills are questioned. |
| I always start at the minimum and load 15 rounds. Then I increase 1/10th of a grain and load 15 more. For example I might start at 23.5 grains and load 15 then I load 15 more at 23.6 then 15 at 23.7 and so on. Then I go outside and record all data such as temp, humidity, altitude, time and so on. Then I shoot 3 (5) round groups and record group size of each and velocity. I do this with every load and this allows me to figure out what my rifle likes to shoot and which load is most accurate from my rifle. You'll be amazed at the differences in group size with just a 1/10th of a grain difference. |
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Barrel wear in the .223 is not a major problem, like say the 22-250 or .223 super duper uber magnums, etc. And the chrome plated barrels are even better at resisting wear.
Best accuracy loads are seldom Max. loads. Everything else being equal (not much barrel whip) the tightest velocity group (lowest SD and ES) is going to be the best accuracy operating point, not the max. velocity or max. load. Some folks on here have had great success with Varget and the 77 gr SMK in the .223 |
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The Ammo Oracle
Unfortunately, I can't edit the link in the FAQ's. I added a link under my post in the Gateway thread. |
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