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Arken Zulus - User experiences

piggers said:
So I use an Arken Zulus with the 35 MOA Mount on my .25 FX Panthera and Also my FX Impact in .25 ( Both FAC - 30 MOA on both )
I Zero at 30 yards for both guns.
I was shooting out to 100+ yards etc and all of the shots were going high - About 2/3 inches at those longer ranges
FPS is correct as measured with the new Garmin Chrono, BC is advertised as 0.119 - 41 Grain Zan Slugs, - all information loaded in the Arken Ballistics and then to the scope.

My question is regarding Scope height. My reticule is high on the screen ( about 3 quarters of the way up ) does this have a direct affect on the scope height or is it a case that my BC information is incorrect and its actually higher than advertised.

Cheers!
Click to expand...
The position of the reticle on the screen when you have zeroed the scope depends on the following main factors:
1. Scope height above the bore of the rifle (the distance from the centre of the bore to the centre of the objective lens)
2. The angle of the scope relative to the rifle (0 moa mount, 20 moa mount, 35 moa mount etc)
3. Muzzle velocity of the pellet/slug
4. Ballistic coefficient of the pellet/slug
5. Drag function for the pellet/slug
6. Distance at which the scope is zeroed

If the reticle is too high or low then a different mount can be used, or the scope can be shimmed on the existing mount to get the reticle nearer the centre of the display

Note that zeroing the scope has to be done before starting to use the ballistic calculator

Once the scope is zeroed you can then use the app to create a ballistic profile that matches the rifle/slug combination you are using.
The app needs only the following data to give accurate results
a. Scope height above the bore (as described above)
b. Muzzle velocity of the slug/pellet (measure this with a chronograph)
c. Ballistic coefficient of the slug/pellet (usually available from the manufacturers website)
d. Drag function - Use G1 rather than G7
e. Distance at which the scope has been zeroed. It is VITAL that the actual distance you zeroed the scope at is entered into the app. If the zero distance entered into the app is different from the actual distance you zeroed the scope, you will NEVER get good results from the ballistic calculator

Cheers

Bruce
 
mealiejimmie said:
The position of the reticle on the screen when you have zeroed the scope depends on the following main factors:
1. Scope height above the bore of the rifle (the distance from the centre of the bore to the centre of the objective lens)
2. The angle of the scope relative to the rifle (0 moa mount, 20 moa mount, 35 moa mount etc)
3. Muzzle velocity of the pellet/slug
4. Ballistic coefficient of the pellet/slug
5. Drag function for the pellet/slug
6. Distance at which the scope is zeroed

If the reticle is too high or low then a different mount can be used, or the scope can be shimmed on the existing mount to get the reticle nearer the centre of the display

Note that zeroing the scope has to be done before starting to use the ballistic calculator

Once the scope is zeroed you can then use the app to create a ballistic profile that matches the rifle/slug combination you are using.
The app needs only the following data to give accurate results
a. Scope height above the bore (as described above)
b. Muzzle velocity of the slug/pellet (measure this with a chronograph)
c. Ballistic coefficient of the slug/pellet (usually available from the manufacturers website)
d. Drag function - Use G1 rather than G7
e. Distance at which the scope has been zeroed. It is VITAL that the actual distance you zeroed the scope at is entered into the app. If the zero distance entered into the app is different from the actual distance you zeroed the scope, you will NEVER get good results from the ballistic calculator

Cheers

Bruce
Click to expand...
Thanks for the info buddy!

Personally I like the reticle further up the scope.


Normal setup - your crosshair is center of the scope.
Zulus 35 MOA plus my Rail - Crosshair is in the upper quarter of the scope.

So the questions im asking is simply does the location of the crosshair in the scope matter when taking into account Scope height or will the scope height always be scope diameter / 2. Barrel Diameter / 2. Distance between bottom of scope and barrel and add together

OR

Because my crosshair is off center do I need to add scope height to compensate where the crosshair actually is ( as my crosshair is above center )
 
The scope height is the scope height, it doesn't change.
It does have an effect on the reticle position when the scope is zeroed, but as I said, above, it is what it is
Once the distance between the centre of the objective lens on the scope and middle of the rifle bore has been measured, that's the value that's used in the ballistic calculator
Once the scope is zeroed and a ballistic profile has been created and sent to the scope, the ballistic calculator uses the centre of the reticle as it's reference point for calculating the holdover
It doesn't matter to the ballistic calculator where on the screen, the reticle is, it always uses the centre of the reticle as its reference point for calculating the holdover

Cheers

Bruce
 
Amazing
mealiejimmie said:
The scope height is the scope height, it doesn't change.
It does have an effect on the reticle position when the scope is zeroed, but as I said, above, it is what it is
Once the distance between the centre of the objective lens on the scope and middle of the rifle bore has been measured, that's the value that's used in the ballistic calculator
Once the scope is zeroed and a ballistic profile has been created and sent to the scope, the ballistic calculator uses the centre of the reticle as it's reference point for calculating the holdover
It doesn't matter to the ballistic calculator where on the screen, the reticle is, it always uses the centre of the reticle as its reference point for calculating the holdover

Cheers

Bruce
Click to expand...
Amazing! So its my BC thats out - as mentioned mine shoots high at the longer ranges.
I will remeasure scope height and work with the BC instead
 
Oooops, a second Zulus unit ordered from @Blackwood Outdoors 🙈
Was always on the cards after being impressed since using my first one. Alpex gen1 will be going on my rimfires and my R10 .22 sub 12 will get the new Zulus👍.
These Zulus's cover all my air rifle needs (night and day out to sensible hunting distances) and for the money they really punch above their weight🙂.
 
I'm not having fun with my Zulus 😱 The first batch of FTT i had were accurate when i had my 3-9 Vector scope on the prophet 2. The new batch of FTT's are all over the place at 30y, I've just been chasing my zero Head bang 65 Not enough hours in the day. Tell me it gets easier please.
 
Willz22 said:
I'm not having fun with my Zulus 😱 The first batch of FTT i had were accurate when i had my 3-9 Vector scope on the prophet 2. The new batch of FTT's are all over the place at 30y, I've just been chasing my zero Head bang 65 Not enough hours in the day. Tell me it gets easier please.
Click to expand...
Is your rifle .177? If yes have you tried Baracuda 8's?
Cheers Steve.
 
Fatbob 59 said:
You need to put a regular scope back on the gun , you've no idea whether the Zulus is the cause of your problems
Click to expand...
Don't need to do that
Clamp up the gun and fire at the target. If the pellets are all over the place then it's the pellets. If they are a close group then it's down to your fitting of the zulus. Mounts etc. The zulus itself will not cause this issue it will be down to fitting.

Cheers

Billy
 
GPCBILL said:
Don't need to do that
Clamp up the gun and fire at the target. If the pellets are all over the place then it's the pellets. If they are a close group then it's down to your fitting of the zulus. Mounts etc. The zulus itself will not cause this issue it will be down to fitting.

Cheers

Billy
Click to expand...
Zulus has all its fittings done up snug so not sure whats happening, I'll try a normal scope just to be on the safe side. (y)
 
Apologies if this has been asked before, but I have just read on another forum that whenever the firmware is updated on the zulus you need to upload your ballistics data again; is that correct as I have not done so to date and have not had any problems....
 
lhj180 said:
Apologies if this has been asked before, but I have just read on another forum that whenever the firmware is updated on the zulus you need to upload your ballistics data again; is that correct as I have not done so to date and have not had any problems....
Click to expand...
Occasionally there might be a need to do so but it is always better to be aware there might be an issue and check the ballistic table that has been loaded by going into system settings menu and selecting version info.

Cheers

Billy
 
It depends on exactly what the update contains.
If there are changes to the way the ballistic calculator works then any existing ballistic table is likely to be deleted
If the update does not relate to the ballistic calculator then you probably won't need to upload a ballistic table again
The way to find out is, after doing the firmware update, simply check in the version item in the System settings menu if the ballistic table is still there
 
I must admit when I updated mine and then tested it when ranging it said no table uploaded so I had to upload mine again 🤷
 
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