Brand new Hatsan 900X in .22... chronoed with FX Radar

H&N FTT 5.53, very hard to push into the breech, 1.5 inch group at 20 yds
FPS
Shot count: 20
Low: 513
Hi: 536
Avg: 523
STD Dev: 5.5
Spread: 23.0

FPE
Shot count: 20
Low: 8.6
Hi: 9.3
Avg: 8.9
STD Dev: 0.2
Spread: 0.8

Webley Accupell 5.50, perfect breech fit, 1.0 inch at 20 yds
FPS
Shot count: 20
Low: 529
Hi: 564
Avg: 555
STD Dev: 8.7
Spread: 35.0

FPE
Shot count: 20
Low: 8.9
Hi: 10.1
Avg: 9.8
STD Dev: 0.3
Spread: 1.2

Falcon Accuracy Plus 5.50, perfect breech fit, 0.5 inch group at 20 yds
FPS
Shot count: 20
Low: 582
Hi: 605
Avg: 600
STD Dev: 6.4
Spread: 23.0
(Those figures are a bit misleading... if I discount the first 3 shots (fired directly after the Accupells), the spread is only 10 fps..)

FPE
Shot count: 20
Low: 10.1
Hi: 10.9
Avg: 10.8
STD Dev: 0.2
Spread: 0.8