.22 Zero

[matt_hooks 188]

Ahhh ok, thought so. Look at your right hand chart. You're near zero point is more like 18 yards than 12.

 

Also somehow your velocity is staying constant, which is giving you a significant error.

Edited January 12, 2012 by matt_hooks

[Simonrees 45]

Heres the info plotted on a graph, so you can see the trajectory. at The light Blue line is Zeroed at 12yds the dark Blue at 75yds, I don't know why the velocity is remaining the same.

 

 

Edited January 12, 2012 by Simonrees

[matt_hooks 188]

Yeah. Look how far below the line of site the dark blue line is at 12 yards. The first zero is definitely more like 18 yards than 12 yards.

[Simonrees 45]

Yeah. Look how far below the line of site the dark blue line is at 12 yards. The first zero is definitely more like 18 yards than 12 yards.

 

I agree but there is still a significant difference between them at 75yds. The issue was that a scope zeroed at 12yds would be "about right" at 75yds, but as this shows it wouldn't be, it would be nearly 3" high. where as if it was zeroed at 75yds it would be a lot closer at 12 and bang on at 18yds. (At least I think I'm reading it correct)

[tegater 789]

I love threads like this, because it is proper constructive discussion. The answer is simple ballistics and has already been raised.

[matt_hooks 188]

Indeed Simon, zeroing at 12 yards will put you a way over at 75 yards. Zeroing at 18 yards would put you bang on at 75 yards. Unfortunately because the effect of drag has been ignored, the calcs are not very reliable.

[paulus 26]

never mind balistic calculations stick some targets up and try it

[thursodog 353]

Paulus hit the nail on the heed.

I also agree the graphs are poop as the velocity at different ranges has not been catered for.

Had a sare heed for a minute or two on this one.

I'm going to have a go at this on the permission and report my findings, great read guys.

 

Cheers Chris.

[Simonrees 45]

Paulus hit the nail on the heed.

I also agree the graphs are poop as the velocity at different ranges has not been catered for.

Had a sare heed for a minute or two on this one.

I'm going to have a go at this on the permission and report my findings, great read guys.

 

Cheers Chris.

 

Nice one Chris, its an interesting subject, If I can get out over the weekend I'll do the same and we can compare results, I would imagine different rounds would produce different results so it would indeed be interesting. I'm aware the software I used doesn't appear to alter the Velocity, but I've run the data through different software, and the results have been almost identical albeit the velocity has changed. I think the data above is correct but the velocity figure hasn't been changed if that makes sense.

[thursodog 353]

Oh crap i'm confused again pal.

Do you know for certain that the sofware caters for air drag on the bullet?

Another important factor is the measurement between the centre of the barrel and the centre of the objective lens.

This will change things too.

Hypothetically speaking for example if i were to shoot Win Super X at 75 yards zero with an objective lens of 50mm with a centre to centre size of say 50mm and you were to shoot the same rimmy with the same gun but a smaller objective lens at say 40mm Centre to centre between obj lens and the centre of the bore also with a 75 yard zero we would get different short distance zero.

Something else to take into account.

Time for a stress relieving beer.

 

Atb Chris.

[paulus 26]

Oh crap i'm confused again pal.

Do you know for certain that the sofware caters for air drag on the bullet?

Another important factor is the measurement between the centre of the barrel and the centre of the objective lens.

This will change things too.

Hypothetically speaking for example if i were to shoot Win Super X at 75 yards zero with an objective lens of 50mm with a centre to centre size of say 50mm and you were to shoot the same rimmy with the same gun but a smaller objective lens at say 40mm Centre to centre between obj lens and the centre of the bore also with a 75 yard zero we would get different short distance zero.

Something else to take into account.

Time for a stress relieving beer.

 

Atb Chris.

only as difficult as you want to make it, take your outfit out stick some targets up and enjoy the winter sunshine

[thursodog 353]

Yer right pal,

Thats the only way to get a proper result for sure, good chewing some fat though, its either that or sit and watch Emerdale with the missis.

Sunshine, fit the feck is that min? ;-)

[Simonrees 45]

Oh crap i'm confused again pal.

Do you know for certain that the sofware caters for air drag on the bullet?

Another important factor is the measurement between the centre of the barrel and the centre of the objective lens.

This will change things too.

Hypothetically speaking for example if i were to shoot Win Super X at 75 yards zero with an objective lens of 50mm with a centre to centre size of say 50mm and you were to shoot the same rimmy with the same gun but a smaller objective lens at say 40mm Centre to centre between obj lens and the centre of the bore also with a 75 yard zero we would get different short distance zero.

Something else to take into account.

Time for a stress relieving beer.

 

Atb Chris.

only as difficult as you want to make it, take your outfit out stick some targets up and enjoy the winter sunshine

 

I've measured my scope to barrel alignment and it comes in a 2". There are so many factors that can change the ballistic figures, but as paulus says nothing proves anything like a round down range!!

[andyf 144]

Hello:

I zero at 50 yards, as that's pretty much the actual 'Rabbit' range' near me?

The .22 drop 6" at 100 yds so I can compensate fairly easily!

Good Luck!