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After shooting the JSB 18gr and seeing their extreme accuracy, I was eager to try these high energy pellets. The tin only contains 200 pellets, so I have a limited number of chances to find a good setup.

25 yard accuracy
I started with the same setup as the JSB 18gr.

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The first and last group were close to sub moa. Not terrible but I need tiny groups. I shot several more groups at 25 yards with various setups and nothing to beat the above groups.

Chronograph

Created: 05-05-2016 03:13:46 PM
Description: JSB monster PW4:5 2700psi
Notes 1:
Notes 2:
Distance to Chrono (FT): 3.00
Ballistic Coefficient: 1.000
Bullet Weight (gr): 25.390
Temp: N/A
BP: N/A
Shots
#     FPS        FT-LBS     PF
16    908        46.49      23.05    
15    908        46.49      23.05    
14    883        43.96      22.42    
13    899        45.57      22.83    
12    906        46.28      23.00    
11    899        45.57      22.83    
10    880        43.67      22.34    
9     857        41.41      21.76    
8     854        41.12      21.68    
7     835        39.31      21.20    
6     837        39.50      21.25    
5     853        41.03      21.66    
4     872        42.88      22.14    
3     856        41.32      21.73    
2     850        40.74      21.58    
1     816        37.55      20.72    
Average: 869.56
StdDev: 29.07
Min: 816
Max: 908
Spread: 92
True MV: 869.86
Shots/sec: 0.10
Group Size (IN): 0.00
At about 2500psi, the pellets sped way up and gave tight numbers.

50 yard inaccuracy

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I was faithfully optimistic for the 50 yard test. Buzz kill. I was expecting to see the group size shrink as pressure dropped and gave more consistent velocities, but that never happened.

100 yard inaccuracy
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Here is a 12 shot group at 100 yards. Only one managed to hit paper. Most would miss the paper by about 6 inches in any direction.

Terminal ballistics
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Complete penetration through the wax block. The temporary cavity was 1/2″wide almost through the entire block.

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Male cowbird at 30 yards. I was holding on the wingbone, but hit his neck instead. Disclaimer: I pulled the skin back to see the damage. The pre disection damage was not visible.

Conclusion
I was unimpressed with the current performance of this pellet. The pellet impacts at 100 yards indicate to me that the pellets are swirling as they travel downrange. Perhaps if I were to slow them down they’d shoot better.

I feel with more time I could get better results, but only slightly better.

Airforce Condor SS .22
JSB Jumbo Monster 25gr
2700psi PW 4:5
869fps ~42fpe

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