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So I’m waiting to get the Zulus when it comes back in stock. I have a couple of the non lrf versions and they are nice. Never thought about utilizing one on a crossbow. 🤯 so say you get your data plugged in and the ballistic calculator isn’t sending arrows where you want after a 20 yard zero. What are the steps to correct that. Just trying to get my 💩 together before it gets here.
 
Discussion starter · #24 ·
Good luck with the LRF version on your xbow Mike. If you're setup data is right 1, you have properly zeroed it #2, you have Ballistic Calculator "on" #3, you should be good. If you find that you have accuracy issues, start by looking at the trigger man.
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A common issue that folks run into is the "Ballistic Calculation" has been accidently turned off. This happens while changes are made to the Ballistic Options / Ballistic Data settings table. Easy to do and easy to fix. Doing that will result in your zero yardage being fine but anything shorter or longer will be off. Range changes done with the LRF doesn't affect a reticle change in this state. This is also easy to "see" if your "Aiming Method" is set to "Hold Over". A new range selection will move the Point Of Aim indicator to that yardage vs 20. If you have BC turned off the POA marker will still be on your 20 yard zero, verses it moving to the new ranged yardage. It's harder to see this in the "Dial In" Aiming Method setting as the whole reticle shifts.
 
Discussion starter · #26 ·
The data set need to make the BC work for these scopes is really the same 7 values as it is for a gun with some lesser impacting values important to gun ballistics but not for our slower crossbows with long arrows. Bulley Length, Twist rate, Temperature and Altitude can be left at the default settings and they make no appreciable impact to arrow accuracy.

This is a snip from the Zulus manual with the 7 key data settings you need to populate.
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Ballistic Coefficient (BC) is a measure of external ballistic performance for bullets, or in our case, arrows. The higher a bullets BC is, the less drop, and wind deflection it will have at all ranges for a given muzzle velocity and environment. There are two standards used for bullets . G1 for the older, flat based, blunt nosed bullets and
G7 for modern, spitzer nosed, boat tailed bullets. Use G1....

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The Ballistic Coefficient that seems to be working best with our crossbows falls into the 0.030 to 0.080 range. I use 0.050 for my Wrath 430.

What xbow are you setting up?
 
Discussion starter · #29 ·
Thanks for the break down. It’s a ravin r9.
You bet. Happy to help.

Use 0.050/G1 as a starting point along with the actuals for the other 6 data elements. That should be a good starting point for the R9.
 
Discussion starter · #36 ·
Set up my Scorpyd ballistic chart last night

had to guess on fps

whatcha think @TX_RDXguy?
@ View attachment 318797
Great start!

The 3.5" scope height seems high but may be right for the Orion. I'd adjust the caliber to the OD of the arrow shaft so 0.350-ish. Outside that, I'd turn on WiFi (phone and scope), press the Sync Ballistic Data option, then check the data in the scope in the Ballistic Options menu and make sure the Ballistic Data Settings for profile "A-Scorpyd" matches.

You're on track from what I can tell.
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I don't know how high the center for the Zulus is from the mount, but on a Scorpyd the top of the scope rail to the center of the arrow is about 1.2" I hope that helps.
Burkie made me an EZ Dial so it's sits a little higher than normal
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