So I did some more testing over the weekend and tonight. I found that the MRD (monsters redesigned) shoot well all the way down to about 840 fps. At 70-yards the groups were 0.75" or less considering some wind effects. The breezes did push the pellet around more at the slower speeds. At 800 fps, they started to fall apart accuracy wise at 70 yards. Overall, the 950-940 fps was the most accurate range, I did not go above that speed so far.
I got a few odd pooky-sounding shots during the shooting - so I went about measuring the head sizes - all were over 5.56mm, so that was not helpful. Then I weighed them - weights were from 25.0 to 26 grains. I weight sorted them in some groups and sized a few to 5.53. I shot the groups tonight and did not notice much difference in the speeds over the weight ranges. There was not much breeze tonight, so the groups were all tight. The 5.53 sized pellets weighting around 25.3gr seemed to have the best groups, but my paper was tearing a bunch (have to rebuild my shooting target), so not the best gauge of accuracy tonight. I had to shoot two target for the 25.1 gr, since it tore a big hole after the 3rd shot.
I did notice that my regulator was giving me higher speeds at higher pressure (225 bar) vs lower pressure (130 bar) (regulator set at 122 bar). I am hoping that this is just the new Huma regulator "breaking in", but my speeds started out around 951 and dropped to 937 fps by the end of the 45-shot string and bounced around a bit. POI did not change much until the speed fell into the 930's.
In the other thread on the MRD, I was speculating that the speeds were causing the accuracy issues - I am flipping that around, it was that the gun was shooting different speeds due to either an internal problem (regulator) or a pellet defect. A few 912's were noted, I put these off to a chrony issue, but now believe it was a pellet issue. So accuracy was not the issue - functioning was issue.
Sunday's Speed Test (70 yards) (speeds were lower due to low fill pressure - had to make air in the afternoon):
- Max: - 935 fps
- #5 - 915 fps
- #4 - 880 fps
- #3 - 876 fps
- #2 - 842 fps
- #1 - 800 fps
Monday's Weight Test (70 Yards):