OK, as I promised TomasT I shot the mixed JSB MRD and FX cards again. Yesterday was a bit blustery with 3 mph wind with gusts to 6mph. What was a bit different was it was coming at about315 deg relative (my 10:30 more or less). So there was more windage spread than in the first time around for both pellets. Rather than attaching the cards I will just post the spreadsheets.
The first two are from 10/14/22. I shot the FX's first, followed by the JSB's. I shot about 10 rounds on a site in target before each pellets turn at the target. I did not change the scope settings between the pellet groups.
This show that if I had adjusted two clicks down I would have had the mean of the shots nearly at o elevation. The max CTC spread here is 11.9mm with 7 of the shots within 1 MOA.
Much more windage spread with the JSB's. This also shows that I should have gone UP 1 click on the scope. so the center of these shots is .75 MOA lower than the FX's. The chrony said that the ave. Velocity, ES and SD for both groups were nearly identical (about 823 fps, 1.9 SD and 7 ES). Strelok Pro says the FX's (orig JSD Monster 13.43 gr) have a BC of 0.026 while the Redesigns have a BC of 0.03, These results seems to say Strelok might have it backwards. The extreme spread on this group is 22mm and only 5 shots are withing 1 MOA.
Today was better weather with only light wind blowing directly at me from the target. Shot the same card, but the JSB's first and the FX's second. I didn't really shoot much better, but the groups seem to tell the same story.
I again left the scope alone. And once again the JSB group has an average elevation .25 MOA below the bulls. Still has the wide flyers even without much wind. This group had an ES of 17mm and 7 shots in a 1 MOA group.
The FX pellets were once again higher up the target than the JSB's. The average elevation is .25 MOA above the bulls. Smaller windage dispersion than the JSB's but I was going high for some reason. This would have been headed for a 192 8 or 9 X card if I shot all FX's. I haven't done that well in .177 yet. This group had a 15mm ES and 8 shots in a 1 MOA group.
So what do you guys think? Is there any difference between these pellets in this rifle? I think there is. But probably I could eliminate much of that by sorting the JSB's by head size and weight. The FX pellets just appear to be a better selection of pellets (from the JSB factory).
Cheers,
Greg