Stable pellet video for a change

Stable pellet video for a change

Joined: April 23rd, 2010, 8:52 pm

April 10th, 2012, 11:04 pm #1

Here is a JSB 18.1gn shot to 100yards at about 950fps.
DAn
http://www.youtube.com/watch?v=pgptrRNC ... e=youtu.be
Last edited by Obturate on April 10th, 2012, 11:04 pm, edited 1 time in total.
Quote
Share

Joined: December 25th, 2011, 9:31 am

April 10th, 2012, 11:14 pm #2

there is some slight wobble in the pellet? (not caused by the wobble of the crosshair)

Are the rifling all at the same direction? If not, could someone make two gun with different rifling shooting hot and comparing the direction of the precession of the pellets? (To see if there is any correlation between the direction of the rifling and the direction of the corkscrew)

Cheers,
Yang
Last edited by fanofairguns on April 10th, 2012, 11:16 pm, edited 1 time in total.
Quote
Share

Joined: April 23rd, 2010, 8:52 pm

April 10th, 2012, 11:55 pm #3

I have a smooth twist barrel with left hand twist. I have altered my receiver and will have to refit the barrel before I can try it. I do remember the st barrel having more instability than the barrel used in this video at 100y.
Dan
Quote
Share

Joined: April 23rd, 2010, 8:52 pm

April 10th, 2012, 11:59 pm #4

Here is a JSB 18.1gn shot to 100yards at about 950fps.
DAn
http://www.youtube.com/watch?v=pgptrRNC ... e=youtu.be
The image is rotated 90 degrees clockwise.
Dan
http://www.youtube.com/watch?v=kateiybv ... e=youtu.be
Quote
Share

Joined: April 23rd, 2010, 8:52 pm

April 11th, 2012, 12:03 am #5

Quote
Share

Joined: December 25th, 2011, 9:31 am

April 11th, 2012, 2:33 am #6

The image is rotated 90 degrees clockwise.
Dan
http://www.youtube.com/watch?v=kateiybv ... e=youtu.be
Cheers,
Yang
Quote
Share

Joined: September 15th, 2000, 3:23 pm

April 11th, 2012, 2:40 am #7

Here is a JSB 18.1gn shot to 100yards at about 950fps.
DAn
http://www.youtube.com/watch?v=pgptrRNC ... e=youtu.be
There was a program on TV earlier this evening about snipers, and long range shooting that made mention of quite a few ballistic terms that we as airgunners tend to overlook. They had one guy analizing what it took him to connect on a shot that ranged a mile and half.

We tend to think of projectiles flying straight, and the truth of the matter is that they just don't. Whether they are being pulled down by gravity, drifted right or left by the wind, spiraling through changing air densities, etc, it becomes even more mind blowing that we can hit anything at all... really.

Between your videos Dan, and the one that Ted posted the other day with the HW100, and some of Harry's that show some pretty drastic instability, I wonder how those same videos would look on days with varying air densities?

I've got an action set up now that I added an external adjuster to. I have it shooting what appears to be some pretty nice little groups, and the first couple of cards I set up at 27 yards look to be promising, if the breeze will die down a little in the next couple of days. I want to try shooting it not only at cards, but at varying distances (measured and repeatable - close to far)) while adjusting the power up and down over a series of shots. I don't have the ability to video and watch what is happening, but am hoping that the targets will help to indicate where the pellets are the most stable.

Regards,
DaveG
See more picts @http://davegcustomstocks.com
Quote
Share

Joined: April 23rd, 2010, 8:52 pm

April 11th, 2012, 11:36 am #8

Examining pellet holes in paper will show a spiraling pellet too. Crosman Premier Heavies in .177 spiral in every barrel that I used. The holes punched in paper always are slightly keyholed. The keyholing is in different positions too, that tells me that a spiraling pellet doesn't necessarily spiral consistently. Here is a vid of one shot through my kid's gun.
Dan
http://www.youtube.com/watch?v=uZ9M47Cn ... ure=relmfu
Quote
Share

Joined: September 15th, 2000, 3:23 pm

April 11th, 2012, 12:58 pm #9

The day before yesterday I was out back doing the 27 yard thing, and watched a BIG, fat fly land on the paper that looked just like that pellet. Spiraling through space till he parked it on the paper. He became little more than a splat pretty quick there after, hehehehe

My plan when shooting is gonna be not only to examine the holes, but look for particular patterns that may arise. Using the 27 yard as the base line, I want to see what is happening on target at closer, and further ranges. Holes moving left or right as a majority, or dead center, etc. Shoot enough, and eventually a pattern will emerge.

Regards,
DaveG
See more picts @http://davegcustomstocks.com
Quote
Share

Joined: April 23rd, 2010, 8:52 pm

April 11th, 2012, 1:51 pm #10

The crazy thing is that the cph even though they spiral horribly still have the best BC that I've tested. My goal is to figure out how to shoot them stabilized, I suspect the BC will be even higher if I succeed.
Dan
Quote
Share