As some of you know, I recently purchased an A4 upper for my Colt lower. Here are some results that I got when I was load testing... working up a good shooting load for my AR.
Nosler 60 grain Ballistic Tip (using "accuracy load" (22.5 grains Benchmark) as described by Nosler)
Group Size: 2.63"
Hornady V-Max 60 grain (using "accuracy load" (22.5 grains Benchmark) as described by Nosler)
Group Size: 1.66"
Nosler 60 grain Ballistic Tip (using 22.9 grains Benchmark)
Group Size: 1.43"
Hornady 60 grain Ballistic Tip (using 22.9 grains Benchmark)
Group Size: 1.47"
All 55 grain loads where using 1.76cc of Benchmark (based upon best accuracy achieved with 55 grain bullets in general in previous testing sessions.)
Nosler 55 grain Ballisitc Tip
Group Size: 1.91"
Sierra 55 grain Blitz King
Group Size: .725"
Hornady 55 grain V-Max
Group Size: .651"
For all groups subtract .223" inches for "center" group size
My AR is a 1:8 stainless barrel with a wylde chamber. No matter what I did, I couldn't get the Nosler 60 grain bullets to group consistently at all. The Hornady 60 V-Max's grouped more consistently than the Nosler, but still not tight groups like I desired. I worked up additional loads for the Nosler 60 Ballistic Tip, and none would group well at all. I think the Hornady 60 grain V-Max could be worked with a little more to get a good grouping, but I decided I wanted to go to the 55 grain bullets.
The Nosler 55 grain Ballistic Tips didn't group well either, as compared to either the Hornady 55 grain V-Max or the Sierra Blitz Kings in 55 grain.
The best group was achieved with the Hornady V-Max 55 grain using 1.76cc of Benchmark powder.
In summary, I found that the Hornady's grouped best of all the bullets, especially in the 55 grain weight. The Sierra's came in a close second, but Hornady is the clear winner... well, at least for my rifle!
Has anyone had good results with the 60 grain bullets? I'm actually surprised I didn't get good results with the 60 grain bullets in my 1 in 8 twist barrel.