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PCP - HPA - C02 Gate => PCP DarkSiders Forum => : PelletPaul February 21, 2009, 11:55:24 PM

: 100 Yard challenge/Cyclone
: PelletPaul February 21, 2009, 11:55:24 PM
Went to the range finally yesterday.  Wanted to shoot both Diana 54 and Cyclone, however the 54 blew a seal the night before.  Send it off to my tuner for repair.  So there I was with the Cyclone.  Windy day 5-15mph wind.  I really should not have shot these long distances and you will see why.  I'am embarrassed by these results.  Shows how critical the wind has effected pellet projection.  A few weeks ago there were claims that a springer could do 2" groups at 100 yards with something like a 2 to 4" holdover.  The Cyclone shoots 29.7FPE and was sighted in at 25 yards.  Holdover for 100 yards was more than 20 inches!  I didn't believe it at the time and now I call BULL.  There are others on these forum that said the same thing. I shot 50 and 100 yards repectfully:
(http://i549.photobucket.com/albums/ii361/akszfizk/PIC00007.jpg) (http://s549.photobucket.com/albums/ii361/akszfizk/?action=view¤t=PIC00007.jpg)
(http://i549.photobucket.com/albums/ii361/akszfizk/PIC00008.jpg) (http://s549.photobucket.com/albums/ii361/akszfizk/?action=view¤t=PIC00008.jpg)
(http://i549.photobucket.com/albums/ii361/akszfizk/PIC00009.jpg) (http://s549.photobucket.com/albums/ii361/akszfizk/?action=view¤t=PIC00009.jpg)
: Re: 100 Yard challenge/Cyclone
: Gene_SC February 22, 2009, 01:41:31 AM
At least you hit the paper on the 100 yard shot Paul. Very nice group at 50 yards though.  Was it the same size BULL for the 100 yard target as the 50 yard target.

Thanks for sharing and now I know my FX Cyclone can do as good at those ranges...
: Re: 100 Yard challenge/Cyclone
: melloroadman February 22, 2009, 03:40:12 AM
You just got done saying it was way to windy and you should not have done it . Then you turn around and call the man a lair . I find no credibility in this post . Sorry Marvin
: Re: 100 Yard challenge/Cyclone
: PelletPaul February 22, 2009, 04:08:31 AM
We'll see what the final results were from other forum members.  I'am just asking to be realistic.    Paul
: Re: 100 Yard challenge/Cyclone
: melloroadman February 22, 2009, 04:19:15 AM
Then give it another try another day when things are right . Marvin
: Re: 100 Yard challenge/Cyclone
: PelletPaul February 22, 2009, 05:47:52 AM
I agree with that.  I'll wait until I get back my 54 from the tuner, then will do it again.  Meanwhile I would like to see pictures not stories about 2" groups at 100 yards with a springer, any springer...............Paul
: Re: 100 Yard challenge/Cyclone
: melloroadman February 22, 2009, 05:58:09 AM
http://www.gatewaytoairguns.com/airguns/forums/thread-view.asp?tid=14592&mid=117891#M117891
: Re: 100 Yard challenge/Cyclone
: PelletPaul February 22, 2009, 07:54:52 AM
http://www.arld1.com/
I should just leave this one alone.  Check out the holdover for a pellet weighing 14.5 from a velocity of 850.  Around 22-24 inches above target at 100 yards, not 4 or 8 inches.  The pellet would have to be traveling at 1300fps to achieve a 4-8 inch holdover.  I checked this calculation on another ballistic chart with same results.  Please explain this melloman?
: Re: 100 Yard challenge/Cyclone
: melloroadman February 22, 2009, 08:06:25 AM
I live in a real world not a chart world . Once the maps of the word showed this world as flat but now we know it is not . Once the charts showed a air plane could not get off the ground but know we know it can . Once  the charts showed man could not get to the moon but now we know he can . I also know my father taught me two things 1 Just because I can not do some thing does not mean the person next in line can not . And second thing is don't kick a dead dog it might just be sleeping and get up and bit you . Marvin
: Okay, guys, enough...
: daved February 22, 2009, 08:21:18 AM
Neither of you is going to change the other ones mind, so let it go.  Next stop, Non-productive Posts.  Later.

Dave
: Re: 100 Yard challenge/Cyclone
: PelletPaul February 22, 2009, 09:00:52 AM
Dave - I'am just trying to learn something.  Apparantly melloman knows something I don't?
: Re: 100 Yard challenge/Cyclone
: MEHavey February 22, 2009, 01:17:10 PM
Sorry guys,... but wind has nothing to do w/ pellet drop, and Paul is correct.
: Follow-up
: MEHavey February 22, 2009, 01:36:45 PM
Sorry guys,... but wind has nothing to do w/ pellet drop, and the rest is pure ballistics.
An 830fps (muzzle) pellet reaches the target w/ ~430fps remaining,for an average velocity of ~615ps over the 100 yards

That means a half second flight time to target w/ a resulting 4-ft drop by pure 1/2aT(sq) math.Tilting the barrel up to compensate for a scope 1-1/2 inches above the boreline when sighting at 25yrds reduces the net drop to ~28 inches, not four. Ain't no way around the simple physics

Paul is correct.
: Re: 100 Yard challenge/Cyclone
: PelletPaul February 22, 2009, 01:47:43 PM
Thanks Mike.  I guess you can't call physics a Liar.
: Re: 100 Yard challenge/Cyclone
: gamo2hammerli February 22, 2009, 09:08:34 PM
Whatever the hold-over.....that's still great shooting with your FX Cyclone!!!!
: Re: 100 Yard challenge/Cyclone
: PelletPaul February 22, 2009, 09:33:01 PM
Thanks Stan.  Try again in a few weeks.           Paul
: RE: Follow-up
: SAVAGESAM February 23, 2009, 12:53:26 AM
MEHavey - 2/22/2009  6:36 PM

Sorry guys,... but wind has nothing to do w/ pellet drop, and the rest is pure ballistics.
An 830fps (muzzle) pellet reaches the target w/ ~430fps remaining,for an average velocity of ~615ps over the 100 yards

That means a half second flight time to target w/ a resulting 4-ft drop by pure 1/2aT(sq) math.Tilting the barrel up to compensate for a scope 1-1/2 inches above the boreline when sighting at 25yrds reduces the net drop to ~28 inches, not four. Ain't no way around the simple physics

Paul is correct.
IMHO, I think you need to be more specific. There are variables that come into play here. A super light weight pellet may leave the muzzle @ 830 fps  but might not be close to 430 fps  after 100 yards. Where as, a heavier projectile (say a 21.1 Gr. .22 Cal. Beeman Kodiak) leaving the muzzle @ 830 fps might arrive at 100 yards with more than 430 fps.  What do you think?
: RE: Follow-up
: MEHavey February 23, 2009, 01:20:20 AM
Good point.  Here's the data...

The case above was the old standard/Crossman Premier 14.3gr/0.0190BC being kicked out at 21.8ftlbs (which is what the/my RWS460 family produces by direct comparison with the 350 in question)

The 21-22 ft lbs is the constant.  Heavy or light, you get roughly the same energy out of the RWS springer.

The heavier 21.1gr Kodiak at pushed out with that 21.8ftlbs starts at 683fps (0.0360BC) and reaches the target at 485fps -- faster than the lighter CP.  But it started slower so average speed is lower and it actualll takes slightly *longer* to reach the target.  As a result, the Kodiak zeroed at 25 hits 33" low at 100.

My personal favorite, the JSB Exact Heavy at 18.0gr/0.0310BC, goes out at at 739fps for that 21.8ftlbs, and reaches the target with 508fps remaining for roughly the same average flight time as the Crosman Premier -- and has the same drop of ~28 inches at 100 yards.
: RE: Follow-up (to the follow-up)
: MEHavey February 23, 2009, 01:25:33 AM
The  really light 12.5gr Super Bear (12.5gr) does go out approaching 900fps for 21.8ftlbs.  But its lousy BC means that its down to 285fps (!) at 100 yards -- making it slowest of them all over the course -- with almost a 40" drop.
: Re: 100 Yard challenge/Cyclone
: melloroadman February 23, 2009, 03:58:38 PM
http://www.uslink.net/~tom1/WindVector.htm
: Re: 100 Yard challenge/Cyclone
: MEHavey February 23, 2009, 04:12:50 PM
A pellet always starts at a speed relative to the stationary muzzle.  But reference the air around it, it quickly adopts different groundspeeds.

A 15 mph headwind will subtract 22fps from the effective muzzle velocity (reference the ground speed)
A 15 mph tailwind will *add* 22fps reference the groundspeed

These are maximum figures, and practical effect is somewhat less that this in both cases, but no matter.  We'll analyze using max effect.

The standard 20ft-lb Crosman Premier start outs at 830fps, and when zeroed at 25 yards strikes 28" low at 100 (no wind).
With the 15mph headwind, it will find itself adopting an apparent 808fps initial groundspeed, and impact 30" low at 100.
The 15mph tailwind will cause an apparent increase in groundspeed to 852fps at the muzzle, and hit 26" low at 100.

: Re: 100 Yard challenge/Cyclone
: melloroadman February 23, 2009, 04:18:16 PM
http://www.gatewaytoairguns.com/airguns/forums/thread-view.asp?tid=14829&mid=120095#M120095
: Re: 100 Yard challenge/Cyclone
: MEHavey February 23, 2009, 04:26:32 PM
Pellets are usually shot with crosswind, which DOES affect lateral dispersion.  But the headwind/tailwind component has little relative effect.  (See above)
: Re: 100 Yard challenge/Cyclone
: MEHavey February 23, 2009, 04:27:29 PM
Pellets are usually shot with crosswind, which DOES affect lateral dispersion. But the headwind/tailwind component has little relative effect on drop. (See above)
: Re: 100 Yard challenge/Cyclone
: MEHavey February 23, 2009, 04:28:15 PM
Pellets are usually shot with crosswind, which DOES affect lateral dispersion. But the headwind/tailwind component has little relative effect on drop. (See above)
: Re: 100 Yard challenge/Cyclone
: MEHavey February 23, 2009, 04:30:30 PM
Pellets are usually shot with crosswind, which DOES affect lateral dispersion. But the headwind/tailwind component has little relative effect on drop. (See above)

(Don't know why this is posting in the wrong sequence)
: Re: 100 Yard challenge/Cyclone
: MEHavey February 23, 2009, 04:31:02 PM
test
: Re: 100 Yard challenge/Cyclone
: PelletPaul February 23, 2009, 09:40:00 PM
Marvin - Good looking chart you sent there.  I need to study the format and try and understand what it is saying.  Wonder what the FT shooters do when the wind is blowing hard?  Bigger targets I guess.       Paul
: Re: 100 Yard challenge/Cyclone
: DanoInTx February 25, 2009, 12:07:19 PM
Thanks Marvin, I had read about the "S" ballistics due to wind a long while ago, but never could find the link again.  This isn't the same link, but is the same info.  Great stuff!!!
: Re: 100 Yard challenge/Cyclone
: MEHavey February 25, 2009, 01:21:15 PM
The resulting 'S' curve, however, is greatly exagerated left and right -- as much as +/- 12 feet left & right at a 1,000 yards for a mere 10mpg wind at right angles for a 200gr 30 caliber bullet starting at 2,800fps.

But as that 15 mph wind swings around to be a headwind or tailwind, however, the rise and fall of the impact point changes only +/- five inches
: RE: 100 Yard challenge/Cyclone
: erskine February 25, 2009, 02:35:56 PM


If you zero a .22 Crossman Premier at 850 FPS for 83 yards. It will never rise more than 5" above line of sight and at 100 yds it will be 6.2" low.



Physics are physics..



... oh and it will still be carrying about 11 FPE on impact.



In a 10 mph full value crosswind (3 or 9 o'clock) it will drive about 13" that means that your group will string +/- 6.5" if your hold is perfect and the wind is variable, so from the looks of your pictures, you had a ten MPH cross wind and you held center.



Good shooting, now hold off for wind and see what you can do.



(http://../jscripts/tiny_mce/plugins/emotions/images/smiley-wink.gif)



: RE: 100 Yard challenge/Cyclone
: MEHavey February 25, 2009, 02:53:54 PM
What did you use for a BC and scope height?
: Re: 100 Yard challenge/Cyclone
: PelletPaul February 25, 2009, 09:43:50 PM
Scope height:  Center to center: 1.5"  BC .033.  
If I were to sight in at 80 plus yards why not just sight in at 100 yards. Then there would be no drop.  But realistically my shots on game are fifty yards and under so sighting in at 25 yards covers anything 50 and under.
Next time I will be going to the desert for test and not that range you see.  Last time a person was shooting a H&H 416 next to me and when he shot he rattled my teeth.  I thought there was a earthquake.         Paul
: Re: 100 Yard challenge/Cyclone
: MEHavey February 25, 2009, 10:43:10 PM

That .416 Rigby's muzzle blast may have rattled your teeth, but I guarentee it rattled more that that on the shooter's end.

 :-)
: Re: 100 Yard challenge/Cyclone
: erskine March 01, 2009, 01:32:56 PM


MEHavey - 2/22/2009  9:17 PM  Sorry guys,... but wind has nothing to do w/ pellet drop, and Paul is correct.



Head winds will cause your pellet to fall short, tail winds will tend to keep it up. I understand that gravity is the primary influence here but anyone that has studied mil dot ranging on big bullets over very long ranges will understand that wind *does* have some influence.



: RE: 100 Yard challenge/Cyclone
: erskine March 01, 2009, 01:39:42 PM


The BC that I have been using is 0.0323 for Crossman Premiers (14.3 gr .22). This is what I measured last year during mild weather at sea level. It is close enough for my poor shooting skills.



Scope height was at 1.5".



If you want me to run you a custom chart for your specific rifle, I can do that. I've done it for other's. If you have a chronograph, I can do a better job for you after you make a couple of measurements for me.







: Re: 100 Yard challenge/Cyclone
: PelletPaul March 01, 2009, 01:48:46 PM
Thanks Mike.  So you can figure the exact BC of my pellet going through a Chrony?  I' am all ears.  Let me know what you want me to measure on my prochrony.
: Re: 100 Yard challenge/Cyclone
: MEHavey March 01, 2009, 05:02:29 PM
You have to set the chrony at different ranges, Paul, and measure the drop in velocity over those distances.  
The further apart the better, but make sure you have that famous "4-inch drop" measure correctly.  
: Re: 100 Yard challenge/Cyclone
: PelletPaul March 01, 2009, 09:31:28 PM
So, if I zero at 25 yards then go 50 yards, that's a 2 1/2" drop.  Then to 60 yards?  Measuring velocity with the chrony?  My wife calls it the famous "6" drop.  HaHa
: Re: 100 Yard challenge/Cyclone
: erskine March 05, 2009, 04:02:12 PM


PelletPaul - 3/1/2009  9:48 PM  Thanks Mike.  So you can figure the exact BC of my pellet going through a Chrony?  I' am all ears.  Let me know what you want me to measure on my prochrony.





Yep, all you need to do is shoot a ten shot string at one distance and then a second ten shot string at any other distance. Probably ten and thirty yards would be best, if that is available. Just give me averages. The average velocity at ten yards and the average velocity at thirty. I can extrapolate the muzzle velocity from those numbers.



Also tell me what pellet you are shooting so I can put save that data.



Then I can calculate BC and generate you a ballistics chart for that pellet at that velocity.

: Re: 100 Yard challenge/Cyclone
: PelletPaul March 05, 2009, 09:50:16 PM
Would 10 & 20 yards work?  My back yard is only 20 yards across.    Thanks  MIke
Paul
: Re: 100 Yard challenge/Cyclone
: erskine March 06, 2009, 03:09:09 PM
Ten and twenty will work fine.