Charge vs. Velocity vs Accuracy ...

Tikka223

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Folks,

I am loading up some 80gr VLDs to be fired through a 1/7" twist barrel. They will be sitting on Winchester cases with CCI BR-4s. From previous outings I've found some "hot spots" with 23.8 gr of Varget and 24.2 gr of Varget.

My question is this. If the 23.8 gr and 24.2 gr perform more or less the same should I then opt to use the 24.2 gr load for more velocity and thus more range or are there benefits to sticking with the slightly lighter 23.8 gr load?

I plan on testing varying seating depths and my efforts will be doubled if I test for both loads.
 
The velocity difference will be negligible if they are performing the same. To know if there is a real difference you will need to test at ~600 and then vertical issues will be more apparent and you should be able to make a better decision on what load will work best.
 
Once you have a promising load at 100 you can then go to 300 yards with it, you will get more than enough info about vertical stringing at that distance. Just make sure you shoot on a reasonably consitent day, from a good rest. Ignore any wind effects and measure the vertical spread. You want your shots to stay within 1 inch at 300 yards (ideally). For accuracy you want to select the best node at the highest (safe) velocity. You may be able to tune it more as you progress your seating towards the lands. Keep in mind that if you are into the lands, the same load may be hotter (more pressure), and the group may open up requireing you to back down a bit.

I find that overly hot loads are erratic and never really tune well.
 
Test further out. Leave the seating depth alone. The best loads will be very obvious.

When you change the seating depth, you change the effective powder charge so you are duplicating your work.

Jerry
 
My question is this. If the 23.8 gr and 24.2 gr perform more or less the same....

Your load sounds like 24 grains....
I would worry less about gaining a bit of velocity and instead focus on deviation and stringing at distance as mentioned.
 
Look at loading data for 223 Rem with 80gr bullets on Hogdons web page or any good loading book and max will be 25gr get closer to there, and seat bullets just kissing lands not 4 to
15 K into lands, remember a hair is 2k
We tested over 6000 rounds with 223 with 80 & 90gr in 223 with 7, & 7.8 twist barrels.
If this load works in your gun, you might find another problem now and then "flyers" send me a PM and I will explain what you have to do then.
manitou
 
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