Quote from: HectorMedina on March 08, 2022, 11:06:51 AMI would test the Crosman 10.5's in Dome and HP configuration. Doesn't the recentish quality crash of Crosman pellets apply to these? A tin of the .22 cal Premiers that I tested showed extreme spread in pellet head size, and I have heard nothing good about these from anyone, after the boxed, selected pellet option was killed.Also, aren't the .177 cal Crosmans made from the same, high-antimony lead that fouls barrels like no other, especially in a high-velocity context? These are the two dealbreakers that make me steer clear of the Crosman option, lest contradictory evidence comes to light. A look at my usual sources tells me that providing ammo for a high-power .177 cal is not unlike hunting for .20 cal pellets, or high-quality .25 pellets. There really aren't many options around, in the 10 - 11 gr. quality dome sector. The prices per pellet also match or exceed the prices for quality .22 cal ammo.
I would test the Crosman 10.5's in Dome and HP configuration.
It's well established that JSB's in general are relatively undersized and have a low release pressure. This is a benefit in some guns, and a detriment in others. In most of my guns, but not all, Exacts shoot substantially slower (even taking their higher weight into account) than H&N or RWS pellets. In some of my guns, they are the top pellets, as per ME. In the present case the Exacts were below par even against the general expectation. Loose cones and bores are not JSB friendly.
Hector, Thanks for the heads up and the properly detailed instructions for catching pellets for analysis! Yet another rabbit hole I must squeeze myself into, when I get the chance!Re: super-magnums at >17 fpe / >23J. Huh? To date, I have chronoed and shot in about a half-dozen springers above that curiously low super-mag limit*; this 350 Mag with its new barrel exhibits far greater differences between pellets than any of the others. I know some have chronoed 100's (of at least low-power spring guns), they have a wider base for making conclusions. My ~20J HW95 .22 cal didn't shoot any pellets I had with great accuracy (I didn't have the reported magic bullet for these, or the FTT 5.55's for testing then). That's the definition of pellet pickiness. Overall, I seem to hear pellet woes quite a bit from the lower-power crowd. Off the top of my head, I have heard of individual H135's (c. 43J) and Hurricane 1250's (c. 39J) that aren't pellet picky at all. Yet, in the end, one pellet that's accurate, and also of a high-BC design, and of a high consistency quality, and available (heh) is enough. *from my perspective, which is of course forged out of discussions, comparisons and observations among the higher power springer community c. 2000 - 2022 (REAL yields):sub-12 fpe: low power12 - 17 fpe: mid-power (HW77-98, AA's, D34, LGV / LGU, FWB Sport, basic Gamo, Cometa 400 etc.)18 - 24 fpe: magnum, or high-power (HW80, HW90, D48-56, 350 Mag, D460, H80-105, Walther Parrus, SIG ASP, FAC Cometa 400 etc.)25 - 34 fpe: super magnum (Webley Patriot, H125-155, Theoben Eliminator, Gamo Magnum, Whiscombe JW80, Beeman 12.5 etc.)35 - 44 fpe: hyper magnum (Theoben Dual Magnum, heavily modded, overpressurised gasrams such as HW90, H135)
Quote from: Ilimakko on July 08, 2022, 04:41:41 AMIt's well established that JSB's in general are relatively undersized and have a low release pressure. This is a benefit in some guns, and a detriment in others. In most of my guns, but not all, Exacts shoot substantially slower (even taking their higher weight into account) than H&N or RWS pellets. In some of my guns, they are the top pellets, as per ME. In the present case the Exacts were below par even against the general expectation. Loose cones and bores are not JSB friendly.This is a good generalization. Typically JSBs are looser fitting. All my 177 Weihrauchs make noticeably better power with JSBs. On the other hand any 22 Weihrauch I've owned or worked on made much more power with H&Ns and RWS than the JSBs.. I can't explain the difference in 20 caliber. There's not a lot of choices but my older 20 caliber makes the same power between the 11.42 FTTs and 13.73 Exacts and my R1 with a new barrel makes almost one fpe less with the JSBs. Uncharacteristically the JSBs fit tighter than the FTTs.I think what you said is correct about the fit as well as weight affecting the start pressure and overall efficiency. Apparently nothing should be assumed and extensive testing with a chronograph like you're doing is necessary. One thing I have learned from testing is that the most efficient pellet with lowest extreme spread may not be the most accurate. One thing I've noticed is that JSBs typically have very thin skirts. When I only had 177, I used to believe that they made more power than others because the skirts ballooned under pressure and sealed better to the bore. Now my experience with 22 and possibly 20 is opposite. Perhaps the lower start pressure of the larger caliber doesn't effectively balloon the skirt?? I'm very impressed with the amount of power you're getting from your 350. Keep going with your test I like reading them. Be well Ron
Quote from: Bayman on July 08, 2022, 09:13:14 AMQuote from: Ilimakko on July 08, 2022, 04:41:41 AMIt's well established that JSB's in general are relatively undersized and have a low release pressure. This is a benefit in some guns, and a detriment in others. In most of my guns, but not all, Exacts shoot substantially slower (even taking their higher weight into account) than H&N or RWS pellets. In some of my guns, they are the top pellets, as per ME. In the present case the Exacts were below par even against the general expectation. Loose cones and bores are not JSB friendly.This is a good generalization. Typically JSBs are looser fitting. All my 177 Weihrauchs make noticeably better power with JSBs. On the other hand any 22 Weihrauch I've owned or worked on made much more power with H&Ns and RWS than the JSBs.. I can't explain the difference in 20 caliber. There's not a lot of choices but my older 20 caliber makes the same power between the 11.42 FTTs and 13.73 Exacts and my R1 with a new barrel makes almost one fpe less with the JSBs. Uncharacteristically the JSBs fit tighter than the FTTs.I think what you said is correct about the fit as well as weight affecting the start pressure and overall efficiency. Apparently nothing should be assumed and extensive testing with a chronograph like you're doing is necessary. One thing I have learned from testing is that the most efficient pellet with lowest extreme spread may not be the most accurate. One thing I've noticed is that JSBs typically have very thin skirts. When I only had 177, I used to believe that they made more power than others because the skirts ballooned under pressure and sealed better to the bore. Now my experience with 22 and possibly 20 is opposite. Perhaps the lower start pressure of the larger caliber doesn't effectively balloon the skirt?? I'm very impressed with the amount of power you're getting from your 350. Keep going with your test I like reading them. Be well RonFunny you mentioned the .20 cal. Yesterday at the range I crony's my .20 HW 50 with botht he JSB 13's and the H&N 11's. Both worked out to 12.08 fpe EXACTLY. -YWish my .177 HW 50's were putting out that!
Hector,Yes, in 1973 (when Dark Side of the Moon was a new album) the FWB 124/127 was a MAGNUM! But things have gone to places unimaginable since then. Many countries have atrociously restrictive airgun laws, where the intent seems to be that nothing but 10M target type airgun shooting is acceptable. But many more countries have no such limitations. The latter places have heartily embraced the full-power HW80 & 90, the D48-56, the 350 & 460, the Patriot, the Eliminator, the big Hatsans etc., in the past 42 years and counting. Heck, someone who as a late teen bought a Magnum HW80 when it was a new model turns 60 this year. The concept of the 30J+ magnum springer has matured, indeed.