Not sure if this is the case. Won't the bullet pass through the line of sight at 25-30m and then drop back low again after 100? (If zeroed at 100)
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Most medium calibres zeroed at 200 will be plus or minus no more than 2" out to about 240 metres, 200 is my zero for the .30/06. To me bush shooting is below 100 metres so I like a 100 zero and just hold over for longer shots.
I always sighted my bush rifle which in those days was a 243 in at 50 yrds and from memory it was still a fraction high at 100 .
Whatever it was it worked well ( just had think that was over 20 years ago ) and accounted for many a Deer and Goat from zero to 150 yrds , most were 60 and in .
PS - A fixed 3 power Leupold was the optic of choice for that rifle.
Yes. Most centre fire rifles shoot flat enough that with a 100m zero the line of sight through the optic has not yet cut below the trajectory of the projectile (if it will cut below). With a 200m zero this first point of crossover comes sooner therefor your line of sight is closer to the line of trajectory at those closer bush ranges.
visualise if you will that red line connecting at hundy and you will se it HAS to climb from muzzle to connect at hundy.... make it slightly high at hundy and it will cross before and somewhere after....so on average be closer to where you want it to be...the theory being my projectile will not be outside of the magic/theoritical 8'' vital area with a centre of vitals aim untill.....250 yards....and the above is a fat,heavy for calibre round nose......
Moved from 2-7 to 3.5-10 due to aging eyes struggling a bit. If I have the money at some point I'd swap it for a VX5 or 6 with 2-10 or 2-12 but happy enough with what I've got now.
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First off 300m is a long shot for me.
1.5-8 x 32 on 308
1-4 x 20 on 30-30
4 x 32 or red dot on .22rf
2-7 x 32 on .22WMR
3-9 x 40 on only CF bolt action tomato stick :ORLY:
I know high mag has its place but my eyes are not to bad yet, and until then I will resist the trend.
Firmly believe its about bolting a scope to a gun, not a gun to a scope. Those big 50+ objective telescopes leave me cold.
Ok. So the graph @Micky Duck has put up shows (a 30-06 maybe?) cutting the line of sight at about 25m? when sighted in at 200m. Where do you think it will cut the line of sight when sighted in at 100m?
Ok, being honest, this shit confuses me at times, so, going off that chart, would I assume a 25m zero sight in crosses back over at 200.
So anything between 25-100 I could expect up to a 3inch high hit, where as past 100 I can expect the opp ?
I have a 3-9x40 on my 30-30, if I don’t dial it down to 3 or 4 I lose sight when I fire as she kicks like a mule.
Should I just be keeping it down to 3x, sight it in at 25 yards, as most my goats have been around 60-150 yard range ?
A ballistic calculator can help clearly show these cross over points and how high/low the trajectory is in relation to the line of sight at each distance etc for specific rifle setups.
Ok. Still not convinced a typical bush rifle (say a 308win shooting a 150gn bullet at 2700fps) or any rifle/bullet combination for that matter, can make the bullet leave the barrel and only rise 1.5"(about the mounting height of your average scope) to get to 100m, and not cross the line of sight well before that). I was hoping a ballistics expert would enter the thread with another graph.:) I would be happy to be proved wrong.
@Shearer I put you slightly wrong. The example photos below are a rough 308 shooting a 150gr soft point at 2800fps. First photo is a 100 zero and shows the point at which trajectory meets LOS is about 70. You will see however that it doesn't really cross over and they stay together to 100 until the trajectory falls away again below LOS.
Second photo is at 200 zero and shows a very clear cross over for a period of time.
Hopefully that makes it clear enough. Also note that this is yards not metres, just a very simple ballistic app I have on my phone for mucking around with numbers.
https://i.ibb.co/Q8zP4Rm/IMG-1798.png
https://i.ibb.co/JrQj2xk/IMG-1799.png
Thanks for that. With 100 yard zero it does meet LOS later than I would have expected. Still, it is never more than an inch low between about 20-140 yards.
Personally I have my 308win zeroed for 150 yards and dial for anything I feel I need to use my range finder for.
PS. Best charge the battery on your phone.:)
the projectile FOLLOWS the line.......thats WHY the graph works for me better than numbers,you can see where its going.... but if yo udo sight in at 25 yards please check it at hundy and again at 150...the programme I use to get that graph is on huntingnut... free for all to use and you just keep tootooing till you work out what works best for you and your style of hunting.....eg my .223 is not 1.5 inches high at hundy..cause it makes sence when 99% of my shots are under 250yards...
the trajectory for your .308 will be a flyshit over top of line of sight at 50 yards..still working on getting graph.
and sorry you are correct I have cut that bit off to shrink it LOL.
yip that worked..... @Survy go and have a play with the numbers...your typical 30/30 load 150grn at 2200fps BC of .220
or 170 grn BC of .242 at 2000fps
also to answer shearers question better. your line of sight is (0 line) on the graph..as thats centre of your scope if bore is 1.5" below it....
As others have said
It depends what you are doing
Some hunters require 15+ Magnification for longer shots
The typical hunter a 3-9 or 2-10 perfect
If you are going for light waight compact and all your shooting is inside 10-50m then a1-4x is ideal
Personally my hunting is typically no closer than 50m and no Further than 300m
I have a vx3 2-10x40
Which I typically carry on 4-6 depending I don’t typically use lower than that but I like having the slight extra power for the longer 300m type shots definitely a bit of a Difference between 9 and 10 more than you would think
I have a 2.5-10x56 illuminated S&B scope on my 308 bush rifle, yes a 56 size bell is big BUT it really pulls the light in when in dark places set on 2.5 it helps my 65-year-old eyes see things again but for years all I had before that was a fixed power 4x36 m8 Leupold scope on it. on my 6.5 I have a 2.5-15x50 scope and a 5-20x50 illuminated scope on my 204 varment rifle and a 3-9x40 on the 22 it's a bit of an overkill for a 22 but it works ok so it stays it came on a rifle I got 25 years ago. but for young eyes a3-9x40 is fine? for a bush hunting rifle that my 2 sents forth.
Looking through all the responses here is very interesting.
One aspect that is obvious is that physical size of the scope is as important as magnification to some .
This got me thinking.
I used fixed 3 and 4 power scopes for years and putting the magnification aspect aside for a minute , the physical size and dimensions of those scopes were a joy to use/carry/ manoeuvre when out and about.
Some how big scopes ( size not magnification) have sneaked their way onto my rifles , and even then my scopes aren’t that big physically compared to some of the modern offerings that people use .
This may end up being more expensive than I thought because a new purchase may be required :)
What would be the most physically compact variable scope with a max of 10 power with good glass and performance ?
I know exactly how far above LOS my 308 is at 50 yards (0.4") and 0.9" high at 100 yards. I have been using ballistic apps and programs for quite a while now and know how to plot a ballistic trajectory. I just preferred someone else do it to show that even with a 100 yard zero the bullet path WILL cross LOS at some point before reaching zero. (Assuming you scope is not mounted a foot above your bore).
I have bought a 4-14 scope for my rabbit gun
must be my age showing.
I want my best, highest magnification scope on the rabbit gun!
I’m a bit confused with the ageing eyes needing more magnification .
I’m in my fifties and over the last 10 years my eyes have deteriorated to the point where I need prescription glasses.
I don’t need more magnification to do/see what I’ve always been doing .
The rifle scope is an optical instrument that when setup/adjusted properly mitigates any eyesight degradation.
3 power is 3 power and 12 power is 12 power no matter what isn’t it ?