Sig BDX AB External Demonstration


Well-Known Member
Nov 12, 2014

There have been some questions about the new Sig Sauer BDX Systems. While they natively have the AB Ultralite Engine (800 yard limit for firing solutions) some of them (2400 models and up) are equipped with dual mode. Which means they can be set to AB External mode and in that case they will connect to a Garmin or Kestrel in order to pull firing solutions. Or to even update the range on the external device. Even in AB External mode they will remain paired to the scope. So you can use your Garmin/Kestrel/(Insert new product you will see soon here) and your Sig 3000 BDX to get firing solutions for ELR events. This works witll ALL BDX Scopes, as long as the paired range finder is a 2400 model or up.

Wind can also be input and electronically calculated with these scopes. It was just not demonstrated in this video. We plan to demonstrate more and more as time goes on.
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Well-Known Member
Dec 30, 2009
Just to be sure, as long as I pair to an AB-E device and my Sierra3BDX, laze a target beyond 800 will update with a reticle that's beyond 800 yards?

I apologize, I was thinking that it'll give you holds for beyond 800 when paired with an AB-E device but possibly not send a new reticle for stuff beyond 800 yds.


Active Member
Dec 7, 2015
If you are in ab external (paired to a kestrel or ab elite device) the rangefinder will get solutions for as far as you can range. If you’re bonded to a scope it will display whatever the rangefinder sends over. If the kestrel sends over 25 moa for your 1000 yard range ballistic solution then the scope shows a 25 moa hold. You just need to make sure that you are at a magnification where 25 moa is in your field of view. If you’re not the bottom led on the reticle flashes quickly until 25 moa comes into your fov.

If you are in ab ultralight and range past 800 yards it displays 0 for elevation and windage which is what the scope displays.


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