JSB Heavy pellets
Lets do some background on the pellets first. They are produced by JSB in the Czech Republic and the current version is the second design. The first design if I remember correctly looked pretty much like a regular dome pellet. They were also a bit heavier at 10.33 grains, the current ones that I weight came to 10.1 on the average. I used an electronic scale. This current design has a pronounced cylinder body which separates the dome head from the skirt. This design makes the pellet rather long giving it a better ballistic coefficient (B.C.). Someone on one of the forums posted the B.C. to be .034. In my articles I do not post the B.C. for pellets as a general rule . That is for several reasons, the B.C. changes with velocity, temperature, humidity and several other criteria. B.C is useful for computers to approximate trajectory for a given velocity. That is great, however; like I said there are too many factors to bring a print out to the range and expect to be sighted in. You may be relatively close depending how accurate the information you fed into the calculations. But it in no way guarantees a zero. And here is the main reason why I donít bother with it. When choosing a bullet for a firearm and for long range shooting I would look at the B.C. Since I have a large variety to choose from the B.C. is a good way to pick couple to test at the range. When the selection comes down to pellets it is rather poor and I am talking about the .177 heavy pellets. Lets see, we have the CPH, JSB, FTS and I think there is a Korean pellet even heavier. OH, and a pointed pellet that comes in at about 12 grains and some change. I am sure I missed some but the supply is spotty at best so I do not include them. I found some 10.7 pellets that looked good and I purchased some but I cant get them on a regular basis so I donít much bother with them. I simply test the pellets I can get on a regular basis, so the B.C. to me is not that important. If I find couple of the pellets that shoot close I simply shoot more groups at different ranges to determine which one my rifle likes. Some may shoot great close but become unstable at longer ranges. Now that I offended the proponents of the B.C. this is how I did my testing.
I used three rifles a S200, Falcon FN19 and a S410H custom. The reason for the S410H Custom, it came out of T.G.A.G. custom shop. Air Arms makes this version in .177 but only 12 foot pounds (fpd). The .22 S410H I believe will generate over 22 fpd. My .177 version will generate 18.5 fpd with the JSB heavies.
All shooting was done from sandbags and off a steady bench. First I shot all groups at 25 yards since I have regular access to that range. Also I have to point out I do not have the same scope on all the rifles. The S410H has a Leupold 12x power fixed. S200 has a T.G.A.G. brand 4-12 x 40, and the Falcon 6-18 x 40 Bushnell. All shooting was done with the scopes set to maximum power. Groups were five shots per target and a total of 20 groups were shot out of each rifle. 100 shots from each rifle, I thought that was good to at least determine which rifle likes this pellet or dislikes for that matter. All groups are measured center to center (c.t.c.) Each rifle was refilled after 20 shots no matter how far the bar meter went. All were filled to 190 bar for the set of 20.
First up was the S200 set to shoot 11.59 fpd with this pellet. I was interested if the English 12 fpd limit would like this pellet. I believe most of the English shooters shoot the 8.44 JSB pellets or something in that weight class. I was very pleasantly surprised how accurate this pellet is.
Largest group .284 c.t.c
Average for 20 groups .201 c.t.c
I would not feel a bit at a disadvantage with the heavy pellet in this rifle. But if I was to use this combination in any match I would have to shoot in some cross winds. Just to see if I have an advantage over the 8.44 JSB which I know my S200 likes.
Next up was the Falcon FN-19, rifle shot at 18.69 fps with this pellet. I believe most shooters in the States shoot at this level. Velocity was at 913 fps and I think this is the best for the heavy pellets as far as accuracy is concerned. This rifle does not have the match trigger and I donít shoot it that much so that could explain some of the larger groups. But overall I was very pleased, in fact this pellet is designated for this rifle.
Largest group ..443 ctc
Average for 20 groups .275 ctc
The last rifle on the bench was the S410H, with this pellet I was getting 18.25 fpd. That is slightly less velocity then the Falcon but nothing significant. With this rifle I also tested the 8.44 JSB for couple of reasons. The rifle is brand new to me and I wanted to determine which pellet to use. And I just wanted to get more shooting in to familiarize myself with it. As usual I tried some CPH but I just did not like how hard they went into chamber. Besides this rifle did not like them. After only 10 groups I could see the S410H did not care for them. The average group for the CPH was .282 ctc. One large group was as much as .608 and the smallest .195 ctc. So I did not test any further with this pellet.
pellet: 10.1 grains
Lighter pellet: 8.44 grains
Smallest group .060 ctc Smallest group .180 ctc
Largest group .358 ctc Largest group .343 ctc
Average for 20 groups .216 ctc Average for 20 groups .248 ctc
Right now I think almost all dealers that carry the JSB line have the heavy pellets in stock. A pellet worth testing in any rifle as long as the rifle is capable of delivering more then 12 fpd. I believe the less powerful rifles have little or nothing to benefit from this particular weight. But looking at all the tiny groups I shot with my rifles I like what I see.
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