 |  | | | |  |  |  |  | Long Range Shooting 280 Meters / 306 yards |  | |  |  |  |
Posted: Tue Jan 26, 2010 6:23 am |
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| Pars |
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| Location: Izmir (Ephesus), Turkey |
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Posted: Tue Jan 26, 2010 11:00 am |
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| rsterne |
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| Location: Coalmont, BC |
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My only question is.... why do I hear the rifle shot and see the pellet hit almost simultaneously?
Bob |
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_________________ Dominion Marksman Silver Shield - 5890 x 6000 in 1976, and downhill ever since!
Airsonal: Too many to count! |
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Posted: Tue Jan 26, 2010 12:10 pm |
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| Pars |
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| Joined: 26 Apr 2009 |
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| Location: Izmir (Ephesus), Turkey |
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| rsterne wrote: |
My only question is.... why do I hear the rifle shot and see the pellet hit almost simultaneously?
Bob |
Because, high power and high bc ammo... |
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Posted: Tue Jan 26, 2010 7:14 pm |
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| sniper |
| Silver Status Member |

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| Joined: 28 Nov 2008 |
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| Location: Star, Idaho |
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| hmmm. the TIME OF FLIGHT seems more like .22 centerfire....imo... |
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_________________ I believe in gun control,
If there's a gun around I
want to be controlling it....... |
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Posted: Tue Jan 26, 2010 7:55 pm |
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| rsterne |
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| Quote: |
| Because, high power and high bc ammo... |
OK.... here are my thoughts.... with the math to back it up....
306 yards = 918 ft.... The speed of sound is about 1120 fps.... that means that the sound of the rifle will take about 0.82 seconds to travel to the camera, which is obviously placed near the target....
You stated 65 FPE.... I assumed that in order to hit anything at 300 yards, the pellet must be subsonic to avoid tumbling as it slows through the sound barrier.... I used a 28.4 gr. EunJin Domed, which at 65 FPE works out to 1015 fps.... that would be about as fast as you can drive a pellet accurately.... Both pellet databases in ChairGun list the BC at 0.035 which is pretty good.... That gives a travel time at 306 yards of 1.62 sec.... which means the pellet willl strike 0.80 sec after the sound of the rifle reaches the camera....
Let's assume that the BC of your pellet is 0.050.... I've never seen anything listed that high, but let's make that assumption.... At the same velocity, the time of flight is still 1.36 sec.... and the pellet would hit 0.54 sec. after the sound of the rifle.... I'm also making the assumption that the rifle could even be heard at over 300 yards....
I'm not saying you haven't shot at targets at over 300 yards.... and I'm not saying you haven't even hit them (although the drop is over 21 feet, and the wind deflection in just a 4 mph wind is 2.5 feet).... I just find it hard to understand how that video could be evidence of that fact.... just based on what I see and hear on it....
Perhaps if you enlighten us as to the specifications (including BC) of the pellet used and the muzzle velocity it would help us to understand the physics of what you are presenting in the video....
Bob |
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_________________ Dominion Marksman Silver Shield - 5890 x 6000 in 1976, and downhill ever since!
Airsonal: Too many to count! |
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Posted: Tue Jan 26, 2010 8:25 pm |
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| sniper |
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i knew you were gonna do that bob.
i was just waiting for your next post.  |
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_________________ I believe in gun control,
If there's a gun around I
want to be controlling it....... |
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Posted: Tue Jan 26, 2010 10:11 pm |
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| Slavia |
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Bob, how often do the batteries wear out on your slide rule? Only kidding; your reasoning and math are sound.
| Quote: |
| the camera, which is obviously placed near the target |
Has to be - at 0:23 you can see a fly crawling around on the target.
| Quote: |
| I'm also making the assumption that the rifle could even be heard at over 300 yards |
Not only heard, but heard as a clean, single event with no delayed reflections. (Even though they're shooting down a lane that's wooded on both sides.) |
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¡Listo! ¡Apunte! ¡Fuego! |
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Posted: Tue Jan 26, 2010 11:19 pm |
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| rsterne |
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| Location: Coalmont, BC |
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| Quote: |
| how often do the batteries wear out on your slide rule |
I actually had several of those over the years.... never had the batteries die, though....
Did you notice on the shot where the rock moves.... the sound of the shot and the motion are virtually at the same instant?.... In addition, it didn't move like it was hit with 12-15 FPE of residual energy, either....
Bob |
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_________________ Dominion Marksman Silver Shield - 5890 x 6000 in 1976, and downhill ever since!
Airsonal: Too many to count! |
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Posted: Tue Jan 26, 2010 11:52 pm |
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| Mar |
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| I can't wait to see the 400, 500 and 600 yd shots. |
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Posted: Wed Jan 27, 2010 12:17 am |
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| sniper |
| Silver Status Member |

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| Location: Star, Idaho |
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time of flight......
.223/5.56x45mm is my favorite.....burner.....
shouldn't this be moved to the B.S. topic??
and hey! MAR! FYI! i can hit house flys at 200 yards open sights
with my crosman 760.... in the rain!!
though the footage is kinda flakey...
you guys are sooooo negative.  |
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_________________ I believe in gun control,
If there's a gun around I
want to be controlling it....... |
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Posted: Wed Jan 27, 2010 2:06 am |
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| Pars |
| Member |

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| Joined: 26 Apr 2009 |
| Posts: 32 |
| Location: Izmir (Ephesus), Turkey |
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Pellet is 30 grain Wasp Magnum, BC=0.083
Muzzle velocity 985-990 fps...
if you have a good pcp like AA or daystate and 60 fpe or more, you can do this...
Wasp bullet, keep energy on fantastic long ranges...
as you can see in chairgun chart |
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Posted: Wed Jan 27, 2010 9:06 am |
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| Slavia |
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| Location: Waseca, Minnesota, USA |
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| Quote: |
| i can hit house flys at 200 yards open sights |
That's fine for you California guys who have the flies stuck to fly paper. Here in Minnesota we dig a piece of lutefisk out of the trash can at the range (you want to be at least 300 yards upwind of it). Then we hit the flies on final approach. I say this with only the deepest respect for your glorious home and its citizens. |
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¡Listo! ¡Apunte! ¡Fuego! |
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Posted: Wed Jan 27, 2010 10:57 am |
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| rsterne |
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Time of flight 1.16 sec - 0.82 sec = 0.34 sec.... The human ear can detect an echo that is only 0.1 sec from the original sound, so a third of a second is easy....
Residual energy is 26.4 FPE.... Why didn't that rock take off?....
Nice setup, BTW.... I'd love to shoot it sometime....
Bob |
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_________________ Dominion Marksman Silver Shield - 5890 x 6000 in 1976, and downhill ever since!
Airsonal: Too many to count! |
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Posted: Wed Jan 27, 2010 11:56 am |
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| oddtodd |
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| I dunno, after seeing the video my BS meter started buzzing real bad. |
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_________________ Airguns: Two starlings talking "Larry, did you hear that? Larry?? LARRY!!!!" |
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