Good points lemming..
Guy asks a question about how to get around something he doesn't care for and it turns into a Leupold bash and China scope advertisement.
Screw the Chinese and Philippine made scopes....
Stop shooting the 6.5 pip squeaks and get a real long range magnum caliber and you wouldn't need to jack your Chinese scope up and down to hit deer sized game from zero to 400 yards.
LFC:
Saying screw Asian sourced scopes is tantamount to saying screw Leupold. There's a reason they can't just roll stamp "Made in USA" on their product.
I don't care to support off shore brands either; however, I care even less for scopes that don't hold zero.
I hunt thick logged over country where you can't see 50 yds. I also hunt western states. There's plenty of instances when there's time for dialing a shot even at 400yds once you've developed that skill set. Dialing is also much more precise, and, thus, more humane, than hold and hope with a standard duplex at anything over MPBR. Stating that there's not a practical application for it does prove a point about your hunting experience, but not the one you're trying to make.
To the OP:
I can't speak to the current crop of Leupolds, but a few years back, a tall turret cap would thread onto a vx-3i once the CDS cap was removed. As has been stated, the the standard cap is too short to fit the threads. Leupold had been good about sending them out when asked. However, you are then stuck with a taller than need be cover to catch brush and clothing. I'd advise your friend to buy a used non CDS version if he doesn't care to twist on it.