Posted: 6/24/2015 4:46:21 PM EDT
| I'm getting ready to start some load development for a RRA AR-15 with 20in barrel and 1-9 twist. Doesn't it matter which bullet to start with, is one really better than the other? I can get 69 SMK's, Nosler custom comp, or 68 Hornady match. Max range for these will be paper and steel at 600 yards. Will be using LC brass, CCI primers, Varget and RL15. |
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Quoted: Try them all to see which shoots best. Remember, in your load development, change only one thing at a time to see if you get an improvement. Also, make sure your 1-9 barrel will stabilize those bullets. My 1-9 does, but I've heard of some that don't. I thought that was just the 75/77s? Sierra says 1:10 or quicker for theirs. |
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Sierra's 69 grain bullet has performed very well in every rifle I've ever fired them in, 1/9, 1/8 and 1/7.
Start at 24.0 grains of RE-15 or Varget and go up to 25.0 grains. You will find a great load inside that range. Or just load 24.5 grains of either powder and go shoot. Some 1/9 barrels can shoot Hornady 75 grain hpbt bullets but not all. Longer 1/9 barrels have a better chance of shooting them accurately in my experience. A 1/9 will shoot any 68/69 grain bullet on the market. I have a Winchester M70 in .223 with a 26" 1/9 barrel that loves Hornady's 75 grain hpbt match bullet. The A-Max won't work. Every rifle is different so it's impossible to say with any certainty which bullet will shoot best for you. You'll have to try them all and find out for yourself. I use 24.5 grains of Varget as my go to load for any 68/69 grain bullet because it's shot so well for me in so many rifles. I seat them at 2.250" to make sure they don't bind in the magazine. I use 23.5 grains of Varget, N140 or RE-15 when loading 75 grain bullets in .223 |
| The Hornady's are long. They look closer to 77's, and dang if I cant remember which load worked better as far as loading for 77 or 69. I'd shoot the middle and go with the CC's as they are superb and the Hornady's have had mixed results, perhaps it's the length. |
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You're going to find that most 69 grain bullets shoot close to the same unless you use careful methods to measure and study the real differences in precision. In other words, if you use a carpenters tape measure or a coin to define your group size, your choice of bullet won't make much difference. And, your rifle/powder/primer/brass recipe is likely to produce different results from my equipment; in fact, it's practically guaranteed.
However, having said that, I have found that IN MY RIFLE, the Sierra Match King Moly coated 69's shoot best followed (rather closely and in this order) by Barnes Match Burner 69's, Sierra TMK (tipped match kings), Hornady 68gr Match, and Sierra 69gr Match King. The Lapua Scenar 69gr bullets are not as good in my rifle, only occasionally shooting 5-shot groups below 1/2 MOA and averaging 0.749 MOA shooting at both 100 and 200 yards and using the best combination of power and primer. On the other hand, Sierra Match King Moly coated bullets essentially always shoot less than 1/2 MOA and produce an average an MOA of 0.393. The Moly bullets often produce 5-shot groups below 0.300 MOA using my best recipe, which is a surprisingly low 22gr IMR 8208 XBR. That's only 92.4% of Maximum charge weight. That recipe produced my all time best 5 shot 69gr group of .155 MOA. Of course, your mileage may vary. Actually, it WILL vary. By the way, these similar-looking Sierra 69gr bullets are have different shapes so the CBTO seating measurements you make for the Sierra Match King bullets are going to be a little bit different from the Moly Coated versions or the tipped versions. |