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Some info on scope height please. I have heard that in Field target

April 2 2017 at 8:52 PM
Don Armstrong  (Login doninva1)
YF12

open and WFTF, you should have your scope fairly high. I have a gun I couldn't get the cheek rest low enough so I raised my scope about an inch. It solved my cheek rest issue but I didn't see any advantage setting up my gun for WFTF so what am I missing. Thanks, Don

 
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AuthorReply
TV
(Login TerryVanpool)
YC

Re: Some info on scope height please. I have heard that in Field target

April 2 2017, 9:04 PM 

Raising the scope has the effect of moving the peak of the trajectory further down range. I sight in at the peak of the trajectory so all corrections are hold over. Sighted in like this a high scope makes for more hold over on the close targets and less on the far targets. Some like this because it is easier to range the near targets. Personally I prefer to put the scope at the height the stock calls for (like you).
Charter member of Over The Hill Gang

 
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Don Armstrong
(Login doninva1)
YF12

Thanks, now that you said that, I did notice the longer ranges take less "clicks". NT

April 2 2017, 9:09 PM 


 
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Skip in WV
(Login SkipinWV)
YF12

But more for near targets. nt

April 2 2017, 9:31 PM 


 
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Boomer
(Login Boomer75)
YF

Don, here is what I do and why...

April 3 2017, 7:42 AM 

When your scope is set "too low" you will have "negative" clicks around your zero zone. What that means is your zero will not be on zero on your scope, it will be -3 to -10 clicks backward behind the zero mark. The only way to assure you only have clicks in a single direction is to get the scope up higher. Like the others already mentioned, based on how high you go and where you set your zero, you will have a ton more clicks for 10 yards than you will for 55 yards.

Here is why this works for me.

I use a Sightron 10-50x60 scope. My scope is 3.1" above my center bore line. I am zero'd at 30 yards using JSB 7.87's at 815 fps. My scope is marked with 8 clicks per MOA with 11 MOA per revolution.

AT 10 yards I have 103 clicks(14.5 moa on my scope).
At 55 yards I have 22 clicks.(2.5 moa on my scope)

The reason I do this is because it is very easy to range the near targets with an extreme amount of accuracy with these types of scopes at 50x. So having to click 103 times for 10 yards is no big deal as long as you know your numbers are on very well.

I can make a ranging error in the 50-55 yard range by 2-4 clicks and still hit the center of the KZ. Example.... If the target is out at 52 yards and I range it at 50 yards, the difference between my 52 and 50 yard numbers is 5 clicks so it is still VERY likely that I will hit the 1.5" KZ. ON the other side of that if the target is at 52 and I range it at 54 yards, the difference in clicks is only 3 clicks so I am still VERY likely to hit the 1.5" KZ on that shot as well.

so basically I worked in the natural human error in the most likely range zone(beyond 40 yards) with as little clicks a possible to account for any ranging errors I can run into in the longer targets. The more you are shooting out of the center of the adjustment range on the scope, the more likely you are to avoid any weird errors so I set my scope up where it is exactly in the center of the click range up and down. It is perfectly on the zero on the factory scope marks because I had Pete Matos build me a custom scope rail for my Steyr to my exact specs to allow the scope to sit perfectly at zero.

Hope this helps,
Boomer
"I am not addicted...I can quit anytime I want...I just don't want to..."

[linked image]http://www.bagaclub.com/

 
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Don Armstrong
(Login doninva1)
YF12

Thanks to everyone. I have a Sightron FT scope in the mil

April 3 2017, 1:13 PM 

version. I have 50 clicks per revolution. Some have told me their Sightron FT have 80 clicks per revolution? 55 yards,shooting 8.4 AA pellets at 790 fps, is 34 clicks and 10 yards is 70 clicks. I am zeroed at 28 yards. Seems to be working well. Thanks again, Don

 
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DonC
(Login DonC)
YF

Great Advice Boomer......

April 3 2017, 2:07 PM 

I duplicated Boomer's kit on his advice. I'm really pleased with my Pete Matos blue anodized custom drooped scope rail.
Thanks Boomer!

 
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Scott Hull
(Login Scotchmo1957)
YF

Low scopes do not cause "negative clicks".

April 3 2017, 6:11 PM 

For pistol and 20fpe, I tend to keep my scopes as low as possible. For 12fpe rifle, maybe a little higher. Except for some inclined/decline shots, I use only positive holdover from my zero. The same would be true if I was clicking.

"Negative clicks" are needed when you do not zero at the apex. Your zero apex will be closer when you go to lower mounts. If you neglect to establish the correct zero for the lower mounts, you will end up with "negative clicks".

 
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Boomer
(Login Boomer75)
YF

Scott, you are correct, the negative clicks comes from the zero not

April 3 2017, 10:05 PM 

correlating with the scope height.

So to be accurate, If you want to have a 30 yard zero in a WFTF set up, you are going to have to get your scope up higher to avoid "negative clicks".

My definition of "negative click" is as such: When you have a zero that does not correlate with the scope height, and you choose a 30 yard zero you will have clicks on the back side of your zero.

This is not something most shooters aspire for and as noted, most of the good shooters that "click" their scopes(not hold over) for range adjustments have between 2-4 inches between the center of their scopes and center of their barrels. This allows you to set a 30 yard zero and not have any clicks behind your zero mark on the scope.

Some people do not use 30 yards as their zero but I do because the way my rig is set up, 30 yards is at the back of the "flat spot" on the top end. Doing this, the way my rig is set up allows me to be certain that everything on the farther side of 30 yards, the pellet is actually moving in the downward arc. This may not make sense to everyone, but on the farther targets I tend to aim higher in the KZ to allow for any ranging errors. This tends to allow my pellet to still "arc" into the KZ as needed. Hopefully this helps me avoid low shots that DING and raise my blood pressure. wink.gif

This may not work for everyone, so that is why I titled my first post, this is how I do it and why. If this helps 1 person, awesome. If this does not align with the way anyone else does it, awesome! You all just learned a little bit about how my brain works. happy.gif

Thanks,
Boomer
"I am not addicted...I can quit anytime I want...I just don't want to..."

[linked image]http://www.bagaclub.com/

 
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LD
(Login lhd)
AR&P

"negative clicks" is due to a less than ideal zero distance

April 3 2017, 10:10 PM 

Using the distance the trajectory peaks with your gun/pellet combo to zero on will never result in "negative clicks" at other distances, as all ranges closer or farther will be "positive".

I always tried to arrive at a system that did NOT require more than a full revolution of the turret at the close distances, and this is normally easier to accomplish with a low scope mounting. BUT, if you want or "need" a high mount, then I normally used a different aimpoint on the reticle, such as the "fatter" point of the 30-30 reticle partway down from the midpoint for shots closer than say ... 15 yards, which avoids the dreaded "full turn off" miss many encounter.

Personally, I have always preferred "holdoff" shooting, and only "clicked" for a couple years in all the decades of FT shooting I have done. With /hunter clsss shooting, which I do nowadays, I find I prefer the scope to be mounted as low as is practical, allowing easy aimpoints on the standard mildot reticle for any distance from 10-100yds with a sub-20fpe gun.

 
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Boomer
(Login Boomer75)
YF

LD, for hunter this makes 10000% sense to me...

April 3 2017, 10:59 PM 

I would want a lower scope to help with hold over. I set up a Hammerli Pneuma in .22 set at 33 fpe for the Gunslynger at the Pyramyd Air Cup a few years ago. I had a Center Point 4-16 set at 4x and found my 'favorable" zero for all 4 ranges I had to shoot. This allowed me to select a zero that had 3 of the distances out of the 4 at a zero point in the center of the scope crosshairs. I never adjusted focus, just set to infinity and moved from one to the other without touching anything. Set at 4x everything was in relative focus and allowed me to move quickly between ranges. It worked out quite well! I typically don't hold over but when I did for this event, it was a lot of fun knowing I had 3/4 distances at zero and only 1 was holding over 1.5 mils so it was fun!

your method for hold over works very well!!!

Thanks,
Boomer
"I am not addicted...I can quit anytime I want...I just don't want to..."

[linked image]http://www.bagaclub.com/

 
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DonC
(Login DonC)
YF

The dreaded "one full turn off".....

April 4 2017, 12:41 AM 

Has caused me trouble several times. However, I recently acquired a Schmidt and Bender scope with 1/4 clicks. I will never have a problem now.
I wish ALL Field Target scopes were made this way.

 
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HookEm
(Login HookEm)
YF

Run the "Chairgun" app, and play with the scope height (link)...

April 3 2017, 8:19 AM 

Chairgun does a nice job of showing trajectory information in table form, as well as graphical.

--EDIT--
Here's the free download:
http://www.hawkeoptics.com/chairgun.html

Here's an introductory video:
https://www.youtube.com/watch?v=Oh0MiNFKJHg


    
This message has been edited by HookEm on Apr 4, 2017 9:18 AM


 
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On line trajectory calc by Brad Troyer MILDOTS

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