I hope me posting this doesn't get redundant but I feel like it's the most accurate way to go about it... especially if you're hunting in a 50"/4browtine unit.
I use a combination of ways to measure. I've looked over so many pictures and videos & seen quite a few moose in person now that there are some bulls that you automatically know he's a shooter as soon as you see him... no need to measure. Width between the eyes works but the most accurate way I've found is to use the reticle on my rifle. Obviously this won't work for archery hunters.
I can judge a moose to see if he's legal from 100yds all the way out to 1000 yards and I feel extremely confident in doing so. You just need to make sure you can get a very steady rest.
Examples:
Range Finder - 300 yards, Moose measures 20MOA
3 X 20 = 60" moose
Range Finder - 475 yards, Moose Measures 13.5MOA
4.75 X 13.5 = 64" moose
Range Finder - 178 yards, Moose Measures 26MOA
1.78 X 26 = 46" moose
The scope I use is a Zeiss V4 4-16X44 with a ZMOA-T30 reticle.
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