Just throw it...
Personally, I believe that my rifle has shown sufficient accuracy with thrown loads (after spending considerable time learning how to throw well) such that I need to spend my time on other issues that I know are enlarging my groups, flag reading, condition that a group is started in, proper use of the sighter target, gun handling....etc.
IMO the best place to do the test that you have suggested would be a top quality shooting tunnel.
Boyd
And..... Yes, yes, yes and yes...
Today I was shooting some new J4 .790 jacketed bullets @ Luther my home range @ 100yds... 10 - 18mph from WSW, SW, SSW, S, SE, SSE, SE, ESE...... Switch and vel change in a hart beat... After serious frustration... Either starting right and finishing wrong OR starting wrong and well once started wrong....Ouch..!
In the end, last 5-shot group went a .280..... Pretty "OK".. But I was happy as I started correctly an finished it... Lotta picking and
only the S, SSE condition did I dare shoot, took all 7min to finish...
Powder measure, was just fine.... It's as Boyd said....
Oh, BTW...
The new J4 .790's are make'n
GOOD bullets.
I'd rather be watch'n flags as opposed to futzing with a scale to get the last .09 throw across the cases... A tunnel may be..
Long range, may be...
But real deal SR Benchrest... Throw it.
cale