GTA
All Springer/NP/PCP Air Gun Discussion General => PCP/CO2/HPA Air Gun Gates "The Darkside" => Topic started by: wll2506 on September 03, 2016, 01:32:38 PM
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Went out this am, with the wind blowing at 12mph at 8am (just a total PITA) ... anyway fired off a few shots before my chronograph blew off my truck bed.
Monsters (25gr) were averaging ~945 fps and the Beasts (34gr) were coming in around 885 fps. I have a new 22 cal 24" barrel on the way which I think should give these pellets another 50 fps. PW was at 6 for the Monsters and 7 for the Beast, 7 is pretty high but did not have a chance to do much testing because I was busy trying to shoot in between wind gust. Getting another 50fps with these heavy pellets starts to make these into heavy hitters for sure. When I get the 24" barrel and shroud I will test for accuracy at 60 yds, and the winner will be the pellet I use ... I'm not going to stock both these two weights .. I will test in my Career 707 .22 also ;- )
I did some calculation on ChairGun but I have no idea the BC of these two pellets ... so I just took the BC of a 22 cal Kodiak at .0360 and gave both of these a BC of .0380 to be conservative. I'm assuming the BC is better than the .22 cal Kodiak ?
If anyone has a rough BC please post as I would really like to get an idea of what it is ?
Thanks Guys.
wll2506
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I came up with a BC of .053 when I tested the Beasts.
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I came up with a BC of .053 when I tested the Beasts.
Great, thank you very much, that helps a lot. What gun did you shoot them out of ?
wll2506
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I got those numbers from my Rainstorm-I.
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You may want to calculate the BC yourself. Some of the data you see on-line is estimated BC; think of it as the "lab-BC" as it asumes a dead stable flight without the rough-edges of rifling.
Also lots of evidence that the BC changes with distance, normally showing the lowest BC at the closest ranges (lets say using 10 yards and 40 yards as your two points) and showing higher BC's when measured at longer ranges (lets say 40 and 70 yards).
Of course, the longer the range, the more likely you are to shoot the chronograph and the harder it is to get a pellet across the screens dead center.
Not hard to do, just be exacting in your measurements. Need a short range velocity reading, a longer range velocity reading, and work it though this on-line calculator.
https://www.pyramydair.com/air-gunsresources/widgets/convert.php?BCalc&u=17 (https://www.pyramydair.com/air-gunsresources/widgets/convert.php?BCalc&u=17)
Do need to measure as exatly as you can (try to get it right to the inch). Distances would be from the MUZZLE (rather than where you are standing) to the MIDDLE of the chronograph. Really need to try to shoot dead middle of the sensor area.
Problem is, darned few of us have two working chronographs (but an embarring number of use have a working and a "dead" chronograph) so we can't get simultanious readings of a shot. So we've got to use one chronograph and shoot recorded strings of shots.
So to be fair, once you get your chrono-data, would pair up the fastest close range with the slowest long range, the slowest close range with the fastest long range, rather than just the average to the average.
Hints:
WAY easier to set up the chronograph and measure back to where the rifle muzzle will be. Just a whole lot easier to fiddle around with where you are than to have to keep resetting the chronograph.
If using two chronographs, find a laser. I'm not so hot on laser sights for sighting, but it certainly does make lineing up two chronographs a lot easier.
It's an on-line caculator, so it doesn't mind working with odd numbers. So if I end up with 39.75 yards rather than 40, just enter 39.75.
Borrow or buy a 100 foot steel tape (get the fishing reel type, where you crank it in by hand...can be had for $14-$18). Over the years, you'll find more uses for it than you expect.
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You may want to calculate the BC yourself. Some of the data you see on-line is estimated BC; think of it as the "lab-BC" as it asumes a dead stable flight without the rough-edges of rifling - etc, etc.
Ribbonstone:
You are correct, but where I shoot I have wind just about all the time, and it makes setting up two chronographs a real pain for me. If I had the $$ for a LabRadar machine I would get it for sure, would make this process real easy. As an example yesterday my Chrono was blown of my truck, and today at 7:30 in the am there were 12-26+ winds .... this is not a fluke ... this kind of wind happens all the time out here (pretty much the norm), and I'm WAAAAY to impatient to deal with it !
wll2506
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Just for the record, my readings were taken at 1yd & 25yds.
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As it is right now I'm sort of re thinking my Beast heavy weight 22 caliber pellet thing with my Condor SS (I can't shoot because of the wind, so I think ... in general a bad thing;- ).
I have .25 cal Condors for anything I want serious power for, not including my .257 Condor, my 22 cal 707 Careers or my 25 Sumatra ! I have a Hatsan 44QE Long that sends 18.1 gr JSB's out at 975fps+ .... is that OK for pigeons, GS and the like ..... Yes - DUH !, and it is a multi shot gun, fine for pest birding IMHO with plenty of power !! Show me a Starling that can take a direct hit with 18.1 JSB at 60 yds with 23fpe and I'll show you a 30 lb starling ;- )
Right now my Condor SS as of yesterday is shooting Monsters in the 940fps area with a PW setting at the 6 spot (and is very, very quiet). I wonder if a little heavier hammer or hammer weight would enable me to re-set the PW down to maybe in the 5ish area, making the gun a little easier cocking and still get the same or a bit more velocity ?, ----- making this gun a short powerful .22 for hunting without the extra length, weight and expense of a new barrel shroud and the new barrel ? ---- I'm trying to talk myself out of installing my new to me very lightly used 24" 22 barrel and then buying a new shroud, and then a extra long case that I will need to store this 48" gun in !. A 25gr .22 pellet going out in the 950fps area is a very powerful airgun by any ones standards, I'm thinking I really don't need this gun to do more ! .
Wish the wind would stop so I could stop thinking and do some shooting ;- )
Continued: 9-4-16
Went back out and touched off 5 shots, I was surprised at how quiet this gun is shooting those Monster heavies in the 930fps ish range. My shots at 66 yds were only about 2 inches to the left because of the wind ... that is not very much drift, again I was surprised, and surprised at how quite the pellet was flying to the target ... I did not hear the usual hiss ... meaning the pellet is flying through the air without much disturbance ;- )
These may be a real good pellet for this gun, without redoing the gun .... a brass hammer weight instead of the steel on may be all that is needed and not a brass 100g hammer.
wll2506