Best Indication of Potential

[TPB12335]

I finally found a load that my Weatherby 223 really seems to like

40 grn match varmint from Berger
Rem Brass
Rem 6 1/2 primer
28 grn of H335
COAL of 2.260

I want to tweak 1/2 grain either way and see what happens. I only had a few of a box left and hope to hit the range again tomorrow so I loaded up 9 of 27.5, 28, and 28.5 grain loads, enough for 3-3 shot groups. I had the gun out today trying some V-Max bullets. My question is should I leave the gun fouled and shoot all 3 loads that way, or clean it before each 3 shot group?

I have noticed that the first few rounds out of a clean barrell is always a bigger group then after, its usually the 3 group where it really tightens up.

So how should I proceed?

 

[sunray]

"...want to tweak 1/2 grain either way..." Try the next load up from your original test loads. If that does get better or gets worse, go back to 27.5 and work up in tenths. As in 27.1, .2, etc. Doesn't always make a lot of difference though. You can fiddle with the OAL to find the distance off the lands your rifle likes.
Clean it first.

 

[TPB12335]

26 is min and 29 is max load, i have tried all of 26, 27, 28 and 29. 28 was the best out of all 4. With that load the best group was a 4 round group of .544" and the total average for the 5 groups shot (all others were 3 shots) was .785, and that was because of a 1.587" where i didn't let the barell cool enough. I just want to tweak the 28grn to see if it makes any difference.

 

[IMagius]

I was jsut reading an older loading manual last night in prep for developing my own 223 loads, and a few lessons that they had there about testing the developed loads ... one of the things they recommended was to have two "known" rounds ... ie: store bought ... fire one of them at the start, then the other as your last round. Mark which one was which. Use the same brand (manufacturer) brass for the "known" rounds as you are using for your reloaded ones.

This apparently "preheats" the barrel and "fouls" it for all the following test loads so that all things are equal for all test loads. Also, the cases from those two rounds can be used as your baseline for measuring for signs of overpressure, etc.. Theoretically, your test loads should measure (within tolerance) of the last Known round that was fired.

 

[mmattockx]

You need to step up in smaller increments with the small powder charge the .223 uses. I would use 0.2gr increments at the most. You could easily miss a node completely with the 0.5gr steps.


Mark