200yards

[Skoll]

Surely something not quite right about that? The flight time was faster than my HMR!

That assumes the audio and visual are completely in sync, and that doesn't always happen on Youtube.

[flims]

According to my Ballistics program the flight time should be around 1.5 seconds, using BC 0.020 and muzzle velocity 280 mps (919fps). He would have to have a holdover of 20ft and the pellet would have 2.2ft-lbs when hitting the bottle.

And by the way speed of sound is 343mps(1129fps)

Im getting realy curious if it can be done though. 200m…
Doing the same calculation on a barracuda cal .25 at 1050 fps one would need a 10ft hold over and the pellet would hit with 12ft-lbs. Flight time would be 1 second and the pellet would travel 4.5ft over the sight line at its highest point.

I will have to test this

hi johan glad you are going for it, we are using the same gun after all.

it will probably take more than a second to get there, even 150meters seems a long way when i squeeze the trigger. i'll bet it will be close to 2 sec for 200m. at 924ft/s 145m is running my elevation turret at 8.5mils(from 35m zero) if i remember well off hand. dat is 1.23m hold over. however im sure that you will break the glass bottle at 200m. im still going through .75" chipboard at that distance i wont run out of elevation this time, i've got 21Mils on my elevation in theory enough to 220meters but havent enough space available for that.

[baz]

speed of sound is 1153feet per second bud thats why rimfire fires at 1050fps to be below speed of sound

Er I know that "bud" But a S410E will only run to around `1000fps max in .22

My subsonic Eley plus .22 rimfire bullets shoot at 1080fps as do all the Match bullets from the best makers

[snock]

Enjoy those eggs, Baz.

[baz]

The speed of sound changes with altitude I am told

Usint a .25 with heavy pellets at 1130fps you have a LOT more chance of achieving reasonable accuracy at 200yds and enough energy to smash a bottle than the one in the film

I think hes a max of 120yds from the target, still pretty good but a LOT different to 200yds as the pellet will be dropping like a mortar after 100yds, as it does on a .22 rimfire

I have shot tin cans at 300yds using .22 rimfire and subsonics, but it was on a dry field so bullet splash was easy to see (and richocets!) the holdover was quite a few feet but I cant remember how many as it was years ago

All good fun though

[baz]

Enjoy those eggs, Baz.

If they want to argue firearm ballistics I am quite happy to get going

[johan_portin]

The speed of sound changes with altitude I am told

Who ever told you that need to do some reading, cuz its bull. Sound is not dependent on pressure, just temperature!

But it’s a common miss conception since its normally colder at higher altitude! Doing the math on this, the post Robert .22 posted earlier is not wrong if he shoots at 35 degrees Celsius. The speed of sound increases with temperature.

[Ka-Boom!]

Yah boo we don't believe YOOOOOOO! Are you sure the witness didn't have a white stick and a labrador with him?
Go on admit it! You were using a 17HMR bipod rested and in perfect weather!!

I realise that you're pulling his leg Nick, but I KNOW Lionel is telling the truth as I've hit that same 300 yard stone too with that (Ian Collins' own) rifle shooting from his back garden across the adjacent field in Bedfordshire.
Yes, it was like hurling mortars (or more precisely, 22LR subs), but it was surprisingly, no, amazingly accurate. I would not have thought it possible for an air rifle, albeit a rather extreme one, to perform like that had I not actually seen it for myself.

Incidentally, the previous poster is correct in his assertion that the speed of sound in air is only linked to temperature.
IIRC, the equation to calculate is:

38.94*Root K = Speed of sound in Kts

Where K = temp in Kelvin.

[baz]

I am sure I read somewhere its to do with altitude and density, however that isnt my particular "thing" I prefer ballistics, and I dont shoot from mountains anyway

[baz]

The discussion I am interested in is the one about a S410E shooting bottles at 200yds with no supersonic crack apparent, I just think it is closer than 200yds

[Gary C]

Who ever told you that need to do some reading, cuz its bull. Sound is not dependent on pressure, just temperature!

But it’s a common miss conception since its normally colder at higher altitude! Doing the math on this, the post Robert .22 posted earlier is not wrong if he shoots at 35 degrees Celsius. The speed of sound increases with temperature.

SoS through a medium is dependent of Density. Greater the density the faster the SoS. My first degree, plus post grad qualifications, was in surveying and this is one of the basic concepts of underwater survey. In terms of air, unless I am mistaken, Air is less dense at higher altitudes therefore SoS will be slower, therefore Baz is right and you are wrong.

A cursory glance shows:

http://en.wikipedia.org/wiki/Speed_of_sound

[baz]

SoS through a medium is dependent of Density. Greater the density the faster the SoS. My first degree, plus post grad qualifications, was in surveying and this is one of the basic concepts of underwater survey. In terms of air, unless I am mistaken, Air is less dense at higher altitudes therefore SoS will be slower, therefore Baz is right and you are wrong.
[/URL]

Aint as daft as I look then

[Ka-Boom!]

Aint as daft as I look then

Actually, you might be...

Speed of sound in air is only linked to temperature. Speed of sound in other mediums is a whole load more complicated!

[Gary C]

Actually, you might be...

Speed of sound in air is only linked to temperature. Speed of sound in other mediums is a whole load more complicated!

Interesting but superficial. Just because the author of this piece says ignore altitude doesn't mean he is literally correct. You ignore altitude because you are using Rho, air pressure. The reason that altitude has an effect is because of the change it has on Rho. If you have already measure Rho then the altitude that Rho is measured at is irrelevent.

If you don't have Rho, and are making a calculation, then you will need the altitude to be able to make it.

http://en.wikipedia.org/wiki/Density_of_air

[baz]

What Gary said