The bunny hop kills momentum, and the speed needed to transition to vertical movement, the idea is to transition from your comfortable approach to a jumping position as quickly as possible. Check my vids on my site, and watch my last few steps, and jump stop.... should see what i mean

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5'10" 173lbs
Standing Vert: 44.5"
Running Vert: 50"
Bench: 300 1x max
Squat 425 1x max
40: 4.26 HT 4.36 Auto