Those numbers look pretty good to me, although I have not tested B.S. 14.3 pellets in awhile. I always use 3 pumps for killing cardboard , 5 for small game, & 8 for larger game/longer distance shots. One thing to remember is that the JSB 15.89 are not going to give you those numbers. Expect about 610+-fps with 8 pumps. I prefer JSB 13.73 for accuracy & B.S. 14.3 for hunting, since they give a little more penetration.
The designs of the JSB & B.S. pellets are different . One may seem a tad more snug than the other. The accuracy between the 2 is very different. JSB's 13.73's are just more accurate . B.S. pellets are not horrible , & will shoot as well as most shooters can shoot. That sounds silly, but it is the truth. When you get the heavier pellets, you may see that you need to adjust the sight a tad, due to their heavier weight & slower speed , or you can just mentally compensate for it. I go through a LOT of pellets for my Sheridans & don't have any trouble finding them . Just don't wait til you are out & then look online for them. Put some tins in your cart & pre-order. Your order will get filled when their shipment comes in.
When you get in the new pellets, whether 15.89 or 13.73, shoot 5 shot targets at 10-20 yards with 3 or 5 pumps. Then compare.
I use to have a lot of old Sheridan pellets in steel cans, plastic yellow boxes, etc. Those pellets supplied my family with a lot of meat in my teen years. I compared those with the JSB 13.73 & was amazed ! NOW, the B & S ARE more accurate than the old ones were.
The TEENS ! I would tell you that it is 80 degrees down here, but I better not.
I'm still shooting the lighter JSB pellet. It always impresses me. I use three pumps for the can on a string at 25 yards and five pumps for the plate at 50 yards. I'm sitting here doing that right now. Took a break to see what was up here. 39 with a wind chill of 31, 10 gusting to 19 making the can a challenge today. Have a nice day folks.
Yesterday I received the JSB Heavy .20 Cal 15.89 from PA. Ran 5 shots over the chrono today in the garage. I found conflicting info on the b.c. for these pellets so I went with the lesser b.c. so the energy may not be accurate.I'm happy with this...Created: 01-08-2022 02:03:06 PMDescription: Blue Streak - Resealed 12/2021Notes 1: JSB Heavy .20 15.89Notes 2: 8 pumpsDistance to Chrono (FT): 2.00Ballistic Coefficient: 0.030Bullet Weight (gr): 15.890Altitude (FT): 990.0Temp: N/ABP: N/AShots# FPS FT-LBS PF5 623 13.70 9.90 4 617 13.43 9.80 3 623 13.70 9.90 2 616 13.39 9.79 1 622 13.65 9.88 Average: 620.20StdDev: 3.42Min: 616Max: 623Spread: 7True MV: 624.91Shots/sec: 0.03Group Size (IN): 0.00