Reel them up under sonar and you can see about where they were running.

Here's a Rapala Dive-to-20 I was messing with trolling for lake trout. Surprised me it was at almost 40 fow.

 

The deepest any bait I fish regularly gets is about 15-18 feet on a long cast with a 6XD. 

I suppose you could achieve almost any depth with a heavy enough bullet weight fished carolina style.  But if you got down 40 feet with yours I'd say you did exceptionally well.

1 hour ago, Tucson said:

I suppose you could achieve almost any depth with a heavy enough bullet weight fished carolina style.  But if you got down 40 feet with yours I'd say you did exceptionally well.

 

Trolling, not on a cast, on a cast you would be lucky to hit the 20 ft mark and only for a few yards.

I'm a horrible deep cranker, it's been years since I've gone beyond 15' 

Twelve to fifteen feet Is about the deepest I can catch them on a crankbait. 

With the big DD crankbaits I have I can get down to 24 feet confirmed because it hit the bottom.

 

But to do this I have a rod and reel designed to throw them and get them to run down that deep.

 

But I will say this it will still wear you out even with the correct gear.

Look up "jacking a crank bait." You're welcome!

Trolling will also give you more depth than simply casting.  

 

Man, anything over 14' or so for hours on end is work.  With my nerve problems, my arms start going numb after about 30 minutes of throwing an XD6, DT16, etc.. 

How deep can you get a crankbait?

 

All the way down to a bass's mouth

I would love to know the different depths vs line type. Ive never fished off a boat with a depth finder so i never know what exact depth im fishing. I know a 10xd with 20lb pp and a 75 yard cast will dive to just this side of china it seems like. 

3 hours ago, CroakHunter said:

  I know a 10xd with 20lb pp and a 75 yard cast will dive to just this side of china it seems like. 

 

You can cast a lot farther than I .

Just now, scaleface said:

 

You can cast a lot farther than I .

7'11 heavy cranking rod. And that was giving it all i got!

19 hours ago, Raul said:

 

Trolling, not on a cast, on a cast you would be lucky to hit the 20 ft mark and only for a few yards.

I just assumed we were talking about trolling. That's the way I would work a carolina-rigged crank.  On a cast, whole different story unless you can cast 1/4 mile or so!