Make sure you can work on air guns! I love to hate this gun. Then I look at what it cost, and the work I (and Mike Mellick at Flying Dragon Air Rifles) did to make it right, and has become a labor of love. Bottom line if you don't want to read further, for $250, you can go wrong. If your mechanically inclined, this will become your new favorite toy, and it will reward you for your TLC.
Took delivery. Packed quite well and the stock is adequately finished. A rough fit around the trigger housing was taken care of with a small file when I removed the action. If you wanted to take the time to do handwork on the stock, the wood is nice enough to reward you.
Right out of the box the gun shot to the left and it was difficult to bring it in. Removed forearm and shroud and shot gun with floated barrel. Scattered results. Replaced shroud only, gun calmed down but groups were still poor. Was using a less than premium pellet, that is to say NOT a JSB or H&N. Purchased JSB Exact 8.44 gn, and H&N Baracuda Match 10.65 gn. Gun immediately started to group 1.5 inches at 20 yards, with two to three fliers out of every mag. H&N performed the best at distance (45 yds). But still shooting way left. Removed receiver/barrel assembly (four screws). Upon reassembly I noticed rear, left hole on air tube/hammer valve assembly was misdrilled. Reamed out lower left corner of hole on receiver assembly and did not have to torque the barrel to reassemble. Barrel lined up well after that by snugging the two screws on the left side of the barrel first and then making up all screws evenly after that. Note: Be sure to remove the small screw and take off the plastic safety tab, out the stock will not separate from the action!!!
Gun came with a 1.98 mm transfer port.
SHOT STRING ONE - Benjamin Hollowpoint 7.90 gn
Fill 3000 psi - Finish 1400psi
FPS Hi 917 Low 791
Avg 855 AVG ft-lbs 12.83
Shot string data lost
Note: Out of box no bell curve. Shot started at 917 fps and consistently dropped to 791. However, POI held around 1.5 inches for 4 mags before shots became erratic and vertical stringing kicked in.
I received three delrin transer ports from MM at Flying Dragon.
I chose the 2.38 mm port and decided to back off the hammer spring tension. The results were encouraging with the speeds inreasing
As can be seen in Shot String Two
SHOT STRING TWO - Crossman Premier Destroyer 7.4 gn
Fill 2800 psi Finish 2200 psi
FPS Hi 957 Low 866
ES 91 SD 29
Avg 913 AVG ft-lbs 13.7
Tried the largest 3.0 mm and the smallest trnasfer port 1.5 mm. Gun shot in the 1050 fps with the 3.0 mm, but the groups were over 1 inch at 10 m. Used two shims under end of shroud/air tube gap and brought groups to 1/2inch. Changed to small TP but not enough power to group well and gun shot low at 10 m. Note: Barrel likes to be supported. Barrel is "whippy" and supports help with resonance.
Started using JSB and H&N pellets. Replaced 1.5mm TP with 2.5 mm and shot an 8 round group 7/16 inch at 10 meters with shroud unshimmed. Ran test over chrony and logged results.
SHOT STRING FOUR -JSB Exact 7.87 at 10 meters. Set hammer spring to 2.5
Fill 2900 psi Finish 2000 psi
FPS Hi 988 Low 907
ES 77 SD 21
Avg 952 AVG ft-lbs 15.84
After about 250 shots the bolt came right out of the back of the action! Back in again to discover that BOTH bolt and hammer actuating screws were loose. Cleaned and assembled with Loktite blue. Loose again after 50 shots. repeat process, but I know they are screwing out gradually! Might use Loktite red next time in.
After rotating and resetting the silencer a couple of times, making up the shroud and forearm at different torques, I found a combination that would shoot well without the shim. I'm now sighted in at 35 yards and grouping 1/2 inch or better off my Caldwell bags. I usually throw one pellet out of ten, and I think this has to do with??
I'm hitting my field target with 1 1/2 inch diameter rings over 95% of the time out to 50 yards with the JSB Exact or the H&N FTT 10.13 gn pellet. I'm using a Sun Optics Air a Tac 4x16x50mm scope (discontinued model). Will try to set targets at 1 inch next time out. The gun is now quite fun to shoot, reliable and accurate enough, and gets about 4 magazines of decent shooting (36) target worthy shots on a full charge.
Next review and pics will be on my new Taipan Veteran .25 cal. It the OTHER end of the quality, fit, finish, accuracy, and power. Its EVERYTHING the Sentry isn't, and its 10 times the price too!!! Money CAN buy love!