.25 JSB Exact Kings 7 groups at 200 yards.
Posted: Thu Feb 11, 2010 1:24 pm
7 successive 5 shot groups shot with the new 25.4 grain JSB .25 Kings.. Average 74.7 mm ctc / 2.94 inches / 1.39 MOA.
These were shot while at the farm to harvest our small lavender crop late January in OZ.
Rifle ; 0.25 cal JB OZ 1B .25 BSA Hornet with John Bowkett regulator .
Sight: Bushnell Elite 6500 AO 2.5-16X set at 16X (30 mm tube 80 MOA elevation range). Sight shimmed to allow for zero settings to beyond 200 yards.
Pellets: JSB 25.4 gr round head King Exacts - unsorted. These are now available from Rob Potter at Potter Firearms Qld.
Velocity: 900 fps MV ; 45.7 fpe.
Bench rested on two sand bags but the rifle still shouldered and held with both hands, front and rear. Four wind flags were placed at 25, 50, 125 and 202 yards. Shots fired when all flags appeared limp. Excellent but not perfect conditions prevailed. (Nothing is perfect Charlie Brown).
7 successive 5 shot groups shot in two sessions ( 4 groups in one session and 3 in the other ).
Sight zeroed to 202 yards ( +192 clicks from 50 yard zero or +51.5 moa ). Apex of trajectory was 41 inches above the sight line at mid-range according to Chairgun..
Note: NO HOLDOVER required excepting for off-setting to separate groups on the first two target cards.
Groups are numbered according to shooting sequence.
Groups #1 ctc 3.20 inches / 81.2 mm and #2 ctc 3.10 inches / 78.8 mm ... Note the aiming circle was drawn around the base of the small JSB pellet tin hence the odd size.
Groups #3 ctc 3.30 inches / 83.8 mm and #4 ctc 2.80 inches / 71.2 mm
Group #5 ctc 2.40 inches / 61 mm. Note first 4 shots in 0.55 inches / 14 mm.
Group #6 ctc 3.45 inches / 87.4 mm ( largest group ).
Group #7 ctc 2.3 inches / 58.4 mm. Note this is just 1.088 MOA ( MOA at 202 yards is 2.1149 inches ) or 54.58 mm.
The overall stats are:
Smallest group 2.30 inches or 1.088 minutes of arc or 58.4 mm.
Largest 3.45 inches or 1.63 minutes of arc.
Average of 7 groups 2.94 inches or 1.39 minutes of arc or 74.70 mm.
Chairgun indicates the remaining energy at 202 yards, at my farm altitude of 3640 ft ASL, as 14+ fpe or over the UK 12 fpe muzzle energy limit
!
The following 3 shot group was put down as an afterthought for comparison with my Brno Hornet centre fire powder rifle roughly sighted-in with a 100 yard zero: Not all that bad for a very light c/f Hornet with the load indicated.
Well, the 5 shot MOA 200+ yd group has still eluded me.
However I can see that it is possible with the .25 cal BSA Hornet and the very well designed JSB Exact King pellets.
Groups # 2, 4, 5, and 7 each had 4 of the 5 shots under the magic minute of arc at the lasered 202 yards range.
These were the first and only 200+ yd groups shot so far with the .25.
I hope some of you find this of interest, especially those with higher power .25 cal air rifles, even though it is outside the square of regular air rifle shooting.
Kind regards, Yrrah.
These were shot while at the farm to harvest our small lavender crop late January in OZ.
Rifle ; 0.25 cal JB OZ 1B .25 BSA Hornet with John Bowkett regulator .
Sight: Bushnell Elite 6500 AO 2.5-16X set at 16X (30 mm tube 80 MOA elevation range). Sight shimmed to allow for zero settings to beyond 200 yards.
Pellets: JSB 25.4 gr round head King Exacts - unsorted. These are now available from Rob Potter at Potter Firearms Qld.
Velocity: 900 fps MV ; 45.7 fpe.
Bench rested on two sand bags but the rifle still shouldered and held with both hands, front and rear. Four wind flags were placed at 25, 50, 125 and 202 yards. Shots fired when all flags appeared limp. Excellent but not perfect conditions prevailed. (Nothing is perfect Charlie Brown).
7 successive 5 shot groups shot in two sessions ( 4 groups in one session and 3 in the other ).
Sight zeroed to 202 yards ( +192 clicks from 50 yard zero or +51.5 moa ). Apex of trajectory was 41 inches above the sight line at mid-range according to Chairgun..
Note: NO HOLDOVER required excepting for off-setting to separate groups on the first two target cards.
Groups are numbered according to shooting sequence.
Groups #1 ctc 3.20 inches / 81.2 mm and #2 ctc 3.10 inches / 78.8 mm ... Note the aiming circle was drawn around the base of the small JSB pellet tin hence the odd size.
Groups #3 ctc 3.30 inches / 83.8 mm and #4 ctc 2.80 inches / 71.2 mm
Group #5 ctc 2.40 inches / 61 mm. Note first 4 shots in 0.55 inches / 14 mm.
Group #6 ctc 3.45 inches / 87.4 mm ( largest group ).
Group #7 ctc 2.3 inches / 58.4 mm. Note this is just 1.088 MOA ( MOA at 202 yards is 2.1149 inches ) or 54.58 mm.
The overall stats are:
Smallest group 2.30 inches or 1.088 minutes of arc or 58.4 mm.
Largest 3.45 inches or 1.63 minutes of arc.
Average of 7 groups 2.94 inches or 1.39 minutes of arc or 74.70 mm.
Chairgun indicates the remaining energy at 202 yards, at my farm altitude of 3640 ft ASL, as 14+ fpe or over the UK 12 fpe muzzle energy limit
!The following 3 shot group was put down as an afterthought for comparison with my Brno Hornet centre fire powder rifle roughly sighted-in with a 100 yard zero: Not all that bad for a very light c/f Hornet with the load indicated.
Well, the 5 shot MOA 200+ yd group has still eluded me.
However I can see that it is possible with the .25 cal BSA Hornet and the very well designed JSB Exact King pellets.
Groups # 2, 4, 5, and 7 each had 4 of the 5 shots under the magic minute of arc at the lasered 202 yards range.
These were the first and only 200+ yd groups shot so far with the .25.
I hope some of you find this of interest, especially those with higher power .25 cal air rifles, even though it is outside the square of regular air rifle shooting.
Kind regards, Yrrah.