GTA
All Springer/NP/PCP Air Gun Discussion General => Air Gun Gate => Topic started by: Bwalton on July 07, 2014, 11:19:37 AM
-
For some reason I feel that there just is not enough pellet choice out there. I think that .177 has a good selection.....be after that it gets kinda iffy. >22 for example you have JSB a good pellet, but to really tune the gun to its best you might need a 16.13gr pellet or a 17gr pellet or a 19 or 20gr pellets. Example the H&N 19gr is the perfect weight for the AT44-10 short or even a 20gr. I tell you 1 or 2 grains makes a difference.
I just feel that there is a big gap in weights in the JSB pellets.....15.89 to 18.13 to 25.39 there is a lot of room from 18-25?
-
I would agree that one more pellet of about 21 gr. would be a good addition to the JSB lineup in .22 cal, it is too big a jump from 18 to 25, and I have not found the 25 gr. to have the stellar accuracy of the other JSB Exacts.... There is a new .25 cal coming out (rumoured to be about 34 gr.) to address the ever increasing power of modern PCPs, and the need, therefore, for heavier pellets....
Bob
-
Bob have you ever tried the H&N Baracuda Hunter Extreme Pellets? its a perfect weight but lacks the distance accuracy, just one more grain is noticeable @ 900fps
JSB 18.13gr @ 75yards......15.55ftlbs
19.09gr @ 75yards.......16.38ftlbs
20.13gr @ 75yards.........17.27ftlbs
-
Yep, tried all the H&N pellets, none of my rifles will shoot them as well as JSB heavies.... I don't know where you're getting your BC's from that show more retained FPE at 75 yards than the JSB's, either.... did you actually measure the velocity at 75 yards and calculate the FPE?.... If so, I'm surprised that a HP will do that well.... or are you starting them all at 900 fps, (which would not take place without resetting the gun) and just assuming the same BC?.... For your numbers to be correct, you would have to have the exact same velocity at 75 yards for all three pellets....
Bob
-
Yep, tried all the H&N pellets, none of my rifles will shoot them as well as JSB heavies.... I don't know where you're getting your BC's from that show more retained FPE at 75 yards than the JSB's, either.... did you actually measure the velocity at 75 yards and calculate the FPE?.... If so, I'm surprised that a HP will do that well.... or are you starting them all at 900 fps, (which would not take place without resetting the gun) and just assuming the same BC?.... For your numbers to be correct, you would have to have the exact same velocity at 75 yards for all three pellets....
Bob
Oh I just used 900fps in chairgun and used the .0360 B.C that I have in there and just changed the pellet weight and looked at the 75yards results.
-
Kinda figured.... I did some BC measurements on a variety of heavy pellets in .22 cal in my QB79 Ninja recently, as follows (measured weights and velocities at 1 yard and 25 yards):
JSB Exact Express 13.4 gr. - BC 0.026 @ 895 fps MV - 18.9 FPE @ 25 yards
JSB Exact Express 14.3 gr. - BC 0.031 @ 868 fps MV - 19.8 FPE @ 25 yards
JSB Exact Jumbo 15.7 gr. - BC 0.039 @ 841 fps MV - 21.2 FPE @ 25 yards
JSB Exact Heavy 18.1 gr. - BC 0.039 @ 810 fps MV - 22.7 FPE @ 25 yards
H&N Baracuda Hunter 18.2 gr - BC = 0.028 @ 806 fps MV - 21.1 FPE @ 25 yards
H&N Baracuda Hunter Extreme 19.1 gr. - BC 0.033 @ 791 fps MV - 22.2 FPE @ 25 yards
H&N Baracuda 21.0 gr. - BC 0.040 @ 762 fps MV - 23.3 FPE @ 25 yards
Gamo TS-22 21.6 gr. - BC 0.034 @ 751 fps - 22.6 FPE @ 25 yards
JSB Exact Monster 25.3 gr. - BC 0.047 @ 696 fps MV - 24.0 FPE @ 25 yards
None of these velocities are high enough to run into serious transonic effects with the heavier pellets, so you can pretty much figure those are the best BC's you are going to get, they will just get worse as you drive them over 900 fps.... The two lightest pellets are already seeing some slight reduction in BC (eg. if you check the RS at 800 fps MV it is 0.030)....
In conclusion, the JSB Exact Heavy actually has more retained FPE at 25 yards than the H&N Baracuda Hunter and Hunter Extreme, and that difference would increase with distance when fired from the same gun.... The Baracuda has a bit of an edge, but the JSB Monster is even better.... On a weight for weight basis, I've never found any other brand that has as consistently high a BC as the JSBs, and I would really love to see an Exact "Magnum" (or whatever you want to call it) at about 21 gr. with a BC of about 0.042.... Assuming it was accurate, that would make a 40-45 FPE .22 cal, accurate hammer, a reality.... for those guns that don't shoot H&N Baracudas accurately enough (which includes all of mine, unfortunately)....
Bob
-
Oh my! Bob a 21gr JSB ;D one can only wish!
-
Yeah, no kidding.... Maybe they read the GTA?....
Bob
-
Talk to JSB .... they will make whatever there is a true demand for .... new molds and tooling cost a manufacturer a lot of money, but if they can fill a demand and make operating profit, while increasing market share ...... winner. Maybe start a poll, send results to JSB. Be proactive, don't wait for someone at JSB to stumble upon a post.