First load development

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agit-prop

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My wife and I just completed our first attempt at methodical load development. We were using CCI primers, once fired Winchester .223 Rem. brass, neck sized and crimped, with Hornady 60gr soft points (flat base). Each charge of Varget was thrown and trickled to weight on a Hornady digital scale. There was a lot of gusty crosswind, so the loads are being judged on vertical spread in inches. All shots were taken at 300yds with a Remington M700VLS with a 1/12" twist

24.4 gr = 2.72
24.6 gr = 3.1
24.8 gr = 4.45
25.0 gr = 1.96
25.2 gr = 3.55
25.4 gr = 4.3
25.6 gr = 2.92
25.8 gr = 5.2
26.0 gr = 2.7
26.2 gr = 1.92
26.4 gr = 3.63
26.6 gr = 2.8
26.8 gr = 4.6
27.0 gr = 1.04
27.2 gr = 1.7

I'm going to take my 4 best loads from above and make 25 of each for further testing and measurement.

Do the results look normal, or is there too much variance in these results?
 
The variation looks a bit extreme - given that the powder increment is only 0.2 g. The strong, variable wind did nothing to benefit the exercise. For example, a group showing 1.7 in spread may have been stringing badly horizontally, without wind. What caused you to settle on Varget and H60 SP's? Did you do a "scoping" exercise with various bullet weights and powders to get to this combination?
BTW - Good shooting otherwise...
 
cosmic said:
The variation looks a bit extreme - given that the powder increment is only 0.2 g. The strong, variable wind did nothing to benefit the exercise. For example, a group showing 1.7 in spread may have been stringing badly horizontally, without wind. What caused you to settle on Varget and H60 SP's? Did you do a "scoping" exercise with various bullet weights and powders to get to this combination?
BTW - Good shooting otherwise...
Click to expand...

The measurements stated indicate the vertical spread. Horizontal spread was discarded in an attempt to minimize the impact of wind on the results.

The powder choice was based on availability and versatility of the powder. I wanted to choose one powder that I could use for all of my rifle loads; .308, .30-06, .303 British, and .223. The H60 SP's were chosen as I wanted to get as heavy a bullet that would reliably stabilize in a 1/12 twist barrel.
 
Stop crimping and see what happens. There is really no reason to crimp unless you are shooting a gas gun or something with more recoil. Try different bullets. Once you find the load that works, start changing seating depth to see if you can fine tune it a bit more.
Since you have a digital scale, try batching your brass by weight.
 
The direction of the wind would have some influence on where the shot lands on the target and a gusty wind makes the validity of the test questionable. You may also get more reliable test results at 100 yards--pick the better performing loads and refine them at longer range. That being said, some bullets in some barrels will give better groups at 200 yards than they do at 100 yards due to the stability characteristics of the bullet.

all of the above is good advice--especoially the "stop crimping" not needed in a bolt gun.

Good luck, 44Bore
 
I would repeat the above tests on a quiet day. Throwing out the horizontal measurement is not a proper indication of group size. Also, unless the wind was exactly 90deg to you, the gusting wind will also move the bullets up and down somewhat.

Quite frankly, I'll bet on a quiet day, your groups will all be much closer to the results you were getting for the 27.0+gr loads. Then begin your 25round refining.

You needed one more opinion anyway..... :p
 
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