scope size & line of sight

[wastrel]

was gonna put this in a reply to my other post & Raj`s answer, but I think it could generate another debate, it`s what this place is all about for me.
I`ve always used the smallest mounts for my scopes I can get away with, my thinking is, the closer the line of sight through the scope, to the barrel ergo flight path of the pellet, the less adjustments I`d have to make for distance changes, so my old smartie tube sight in the 80`s on my Airsporter would require less adjustment (holdover) than my x50 Nikko Stirling or x40 Hawke once sighted.
now, the debate bit, looking at FT/HFT shoots, there`s all manner of sights & sizes of objective lenses, on each gun, but surely a large, or huge, as I`ve seen on some rifles, OL, will mean more compensation over different distances, ergo, you`d be making a FT/HFT more difficult unless you know for certain what your aim points are for the distance you`ve estimated?
put this another way, wouldn`t a scopes line of sight, sitting lower on your gun, being closer to the flight of the pellet, be as advantatious as the flatter flight path of a .177 pellet, compared to a .22?

[Raj]

The lenses on FT are huge by definition because it is all about ranging and clicks. The high magnification is essential to be able to score the way they do. With our hunting smartie tube scopes, we would be left at the bottom of the league if we tried FT

[raygun]

If you have your scope mounted high on your rifle you will "flatten" the trajectory curve at further distances.
If you have your scope mounted low on your rifle you will "flatten" the trajectory curve at shorter distances.
This will mean that you will need more holdover with high mounts at shorter distances and more holdover with low mounts at longer distances.

ATB
Ray.

[devonhunter]

If you have your scope mounted high on your rifle you will "flatten" the trajectory curve at further distances.
If you have your scope mounted low on your rifle you will "flatten" the trajectory curve at shorter distances.
This will mean that you will need more holdover with high mounts at shorter distances and more holdover with low mounts at longer distances.

ATB
Ray.

You learn something everyday. I thought that low mounts just meant a "flatter" trajectory at close and long ranges altogether.

[wastrel]

If you have your scope mounted high on your rifle you will "flatten" the trajectory curve at further distances.
If you have your scope mounted low on your rifle you will "flatten" the trajectory curve at shorter distances.
This will mean that you will need more holdover with high mounts at shorter distances and more holdover with low mounts at longer distances.

ATB
Ray.

AHA! BUT, (I've never shot ft/hft) don`t these shoots consist of targets from 7-45m? sure I read that somewhere on here?
so I say again, cos I don`t regard 45m as a really long distance with modern guns & ammo, cos if I can shoot at 45m (target, & I have)anyone can! so, with the smallest OL & shortest mounts, you`d have an (admittedly small) advantage? Ray?

[raygun]

At a power level of 12FPE you will find a difference between high and low mounts as I described in my post. If your just going to shoot at one distance it matters not as you would zero at that distance and hold over/under would be immaterial.

When I did pest control I very rarely shot at more than 30 yds and low mounts would suffice. Shooting HFT between 8 and 45 yds I use medium mounts with a 30yd zero and a power level of 11.4 FPE. Other people will use different because it suits them to do so.

I'm presuming that OL is Objective lens and that has nothing to do with the distance you are shooting over.
For HFT most people use a smaller OL as they give a much better depth of field. For FT they are not concerned with this so tend to use large OL's and big mags to ensure good range finding which need a very short depth of field.
For hunting I wouldn't consider any OL above 40mm and maybe less.
Perfect eyesight will have an exit pupil size of around 7mm, which will reduce with age to around 4mm.
Objective size divided by magnification will give exit pupil size (ie. 40mm divided by 5 mag = 8. Too big for most people).

ATB
Ray.

[Raj]

AHA! BUT,[/color] (I've never shot ft/hft)

You really ought to give it a try, Sy.
For a long time, I was perfectly at peace with my rifle and my skills. Then I tried a few FT / HFT courses and realised how much more to it there was. Result? My hunting improved many fold once I got my head around why FT / HFT was so different and difficult compared to what I was doing before.

[mikeygasbag]

HFT is normally 30 targets set out between 8 and 45 yards. There are forced positional shots, prone, kneeling and standing. There are 2 unsupported and 4 supported positional shots within the 30 targets. Once you have taken your first shot, you are not allowed to alter any rifle/scope settings, therefore range finding targets has to be done by eye. Some shooters also set up to use scope blur to help with range finding. Multi aim point scopes are the norm in HFT to help with hold over/ hold under. Knockdown kill size's range from just 15m.m.

I can't tell you much about FT as I have never shot it. I do know that the positions are sitting, kneeling and standing. I also know that the larger scopes are used in FT for range finding purposes. The shooter is allowed to adjust parallax so that when the target snaps into focus, a readout of distance is attained. The shooter then 'dials in' that distance using the elevation turret, enabling crosshairs to be used for every shot.

Maybe an experienced FT shooter can supply more information.

I personally use high mounts on both my HFT and hunting rifles. This means I have to be very accurate with my close in range finding (8 to 15 yards), but does allow a little more margin for error at longer distances (30 to 45 yards). I have tried low and medium mount set-up's, low mounts are not good for me because I'm too hunched up and not relaxed. Mediums are okay, but some medium mounts do not allow for 10 shot magazine clearance on my hunting rifle. I like to have both my rifles set up exactly the same, so it doesn't matter which one I am using, the aim points are the same for both.

I hope that is of some help

Mike.

[mikeygasbag]

So long as you are happy in what you believe, then there is no case to answer. So long as the aim points you use in various circumstances work for you, then that's fine by me. If you want to tell us what works for you, then that's useful information that others may want to try.

It's a shame you live so far away, I'd love the opportunity to introduce you to Fort Airgun Club, and to experience what a thoughtfully set out HFT course is really like. We could then go out on one of my hunting permissions, high shots, low shots and open ground shots, they are all possible. Then we could nip to my local and discuss the days activities over a pint or two.

Mike.