For what it is worth, I have finished about six months of testing with my Air Arms S510 rifles in .177, .22, and .25 calibers. I have shot thousands of rounds of nearly every brand and type of pellet, using my indoor 18 yard range in a very controlled environment, testing through a chronograph, measuring penetration using reams of 20 lb paper (not sure how conclusive this really is as paper stacked is much harder than flesh and tissue), and finishing up outside at 35 and 50 yards. Three ten shot groups of every pellet were shot against each other for best grouping, narrowing in each caliber down to the top 10 pellets, then again to establish the top three pellets, and then the very best pellet performance (accuracy consistency and grouping). In my rifles, the best pellets were:
.177 = (1) JSB Heavy. 10.34 grains, @ 996 fps avg, punching through 107 pieces of paper @ 18 yards
.177 = (2) Air Arms Diablo Heavy Field, 10.30 grains, @ 994 fps avg, punching through 96 pieces of paper @ 18 yards
.177 = (3) Beeman Kodiak Copper Plated, 10.19 grains, @ 955 fps avg, punching through 96 pieces of paper @ 18 yards
All three of the above shot - -.375" groups @ 18 yards and -1" groups @ 50 yards with the JSB Heavy's averaging just over 1/2"
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.22 = (1) H & N Baracuda Hunter, 18.21 grains, @ 794 fps avg, punching through 69 pieces of paper (this is a hollowpoint and was the real surprise of the bunch)
.22 = (2) JSB Exact Match Jumbo Heavy, 18.13 grains, @ 818 fps avg, punching through 91 pieces of paper
18 yard groups were nearly single hole with 50 yard groups averaging of 3/4" or less
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.25 = (1) JSB Match King, 25 .39 grains, @ 746 fps avg, punching through 88 pieces of paper
.25 = (2) JSB Match King Heavy, 33.95 grains, @ 622 fps, punching through 111 pieces of paper
.25= (3) Air Arms Falcon Diablo Field, 25.40 grains, @ 712 FPS avg, punching through 61 pieces of paper
All three were deadly accurate with both #1 & #2 producing 18 yard nearly single hole groups of +/- .375 and 50 yard groups of +/- 1/2"
I hope this helps all or you in some way or another.
.177 = (1) JSB Heavy. 10.34 grains, @ 996 fps avg, punching through 107 pieces of paper @ 18 yards
.177 = (2) Air Arms Diablo Heavy Field, 10.30 grains, @ 994 fps avg, punching through 96 pieces of paper @ 18 yards
.177 = (3) Beeman Kodiak Copper Plated, 10.19 grains, @ 955 fps avg, punching through 96 pieces of paper @ 18 yards
All three of the above shot - -.375" groups @ 18 yards and -1" groups @ 50 yards with the JSB Heavy's averaging just over 1/2"
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.22 = (1) H & N Baracuda Hunter, 18.21 grains, @ 794 fps avg, punching through 69 pieces of paper (this is a hollowpoint and was the real surprise of the bunch)
.22 = (2) JSB Exact Match Jumbo Heavy, 18.13 grains, @ 818 fps avg, punching through 91 pieces of paper
18 yard groups were nearly single hole with 50 yard groups averaging of 3/4" or less
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.25 = (1) JSB Match King, 25 .39 grains, @ 746 fps avg, punching through 88 pieces of paper
.25 = (2) JSB Match King Heavy, 33.95 grains, @ 622 fps, punching through 111 pieces of paper
.25= (3) Air Arms Falcon Diablo Field, 25.40 grains, @ 712 FPS avg, punching through 61 pieces of paper
All three were deadly accurate with both #1 & #2 producing 18 yard nearly single hole groups of +/- .375 and 50 yard groups of +/- 1/2"
I hope this helps all or you in some way or another.
