Thread: Frustrating arvo at the range. Powder charges.

I’ve been looking at loading using Eric Cortina’s method. @dannyb went down the same line I think.

I’m starting with the .223 as it’s more economical given the cost and availability of everything at the moment.

So a few weeks ago I set up a loading length of 1.923” and starting charge of 22gr of 2206H going up in .4gr increments. 5 shot strings with the crony to see what the speeds are and not worrying about group sizes. Crony is a Magneto V3.
SDs were probably averaging 30 and ES of 34 to 86 as I was going through the charge groups. Hit 24.0gr and SD drops to 2.8 and ES of 8. Bingo! Average speed 3021.

So today I thought I’d load for seating depth with 24.0gr 2206H and all going well I should fine a good node. I loaded 10 at the original length of 1.923”, the first 5 were to confirm speeds and SD and the second 5 to see if there was a change of group sizes after taking the V3 off. The seating depths were then adjusted at 3 thou increments for the remaining 7x 5 shot lots.

Well fuck. First 5 shot speeds ranged from 2947 to 3030 (initial 5 from the previous range day at 24gr were 3017-3025). So I chucked all 10 down and the average was 2975, SD 31 and ES 83.

So I’m thinking that the charge weight hasn’t been consistent between my two case loading sessions and going off the speeds it’s probably light of the 24gr load I shot previously. (Last time 23.6gr was averaging 2960 and SD of 27.7). I’m using Ohaus 5-10 beam scales and it is possible to have to weight on the beam sit in slightly different positions in the same notch. Also when it’s zeroed the fixed ‘0’ doesn’t line up with the ‘0’ on the screw weight which is annoying but doesn’t affect functionality.

So….
Is it worth looking at some decent electronic scales? I see @Bos has just asked that question so will keep an eye on that thread too.
I also didn’t shoot the remaining 35 rounds as wasn’t sure whether I’d be wasting my time. Also the bloody wind started getting up. So even though the powder weight appears to be slightly light, is it worth shooting the loaded rounds and seeing if there is a good node? Then increase the charge until the average is around that original 3021? Will a small powder charge change move the node much? Only other option being to pull all the projectiles and start again.

Ironically, after the first shot foulers it shot an 8 shot group at 100m just under .300”. I should just be happy with that but it would be good to achieve the total consistency as I’ll do the same with the .284 next.