Hanging large TV and media cabinet on cement block covered with drywall

Question

I'm planning on hang a 75" TV and a media center on my wall. It is cement block covered with drywall. Drywall is installed using some sort of metal furring strips so there are no studs.

I believe all I need is the right hardware, isn't it? This should help explain the scenario:

The best I could come up with are sleeve anchors like this one: Dynabolt Sleeve Anchors, but I'm really concerned about the gap between the drywall and the cement blocks though.

Also, in order to determine the right length for the sleeve anchor I will need to know the thickness of the cement block wall itself (between it's exterior and it's core), which I don't.

TV is around 80 lb according to website (Samsung QLED 75") and will be mounted with a TV bracket.

Media center is 70 inches wide and it has 6 holes that I can use to basically hang it. It is between 80 to 100 lb (give or take): IKEA Media Center.

To summarize:

Is sleeve anchor the best (safest) approach here? If yes:

1. How long they need to be to make sure they don't go "through the block's core"
2. How thick they need to be to support this weight?

If no, what it is then? How are people approaching this challenge?

EDITED 10/21/2018 - Snaptoggles

I attempted to use Snaptoggle but it didn't work well. After making 4 x 1/2 inch holes for the tv mount and put the Snaptoggles in place, I can't get the bolt in not matter what I do.

My best guess is that the track/anchor is angled. For the bolt to go smooth the little track/anchor that goes inside the block needs to be in a perfect 90 degrees angle with the plastic part that holds it together and also guides the bolt.

This illustration should help explain it:

EDITED 12/14/2018 - Done

So here is what I did (based on some feedback):

1. I opened the wall just enough.
2. Used plywood to close the gap between the drywall and cement blocks (tapcons were use to secure the plywood into the blocks). This should prevent the TV mount screws from bending.
3. Used tapcons to secure the TV mount.

Here is a Tapcon performance table

Based on performance table for 1/4" tapcons and what you see in these pictures, do you believe it is safe to hang an 80 pounds TV in there?

Answer 1

The walls of standard 8" concrete block is only about 1-1/4" thick, which is not much depth for embedment for expansion type anchors. For this reason I think it's safer to use a toggle of some kind in block.

I find this type of toggle is easiest to use and will work fine even with drywall and hat track on top of the block:

The one in the picture is branded "Snaptoggle" but there are many brands.

Although 1/4" toggles would probably have enough strength to mount the bracket right on the block, I'd bump up to 3/8" toggles to compensate for the gap.

Answer 2

I think I would fill the gap with blocks of wood. That's the only way you will get a solid connection. You could put in multiple small blocks, but fewer bigger blocks would be easier. You cut out the drywall, put in a block and then put the piece of drywall back on top of it. Put some sticky fiberglass drywall tape over the seams, and then apply three thin coats (if your good) of drywall joint compound. Then primer, then paint to match. Then drill holes big enough for the fasteners of your choosing. I would think that tapcons would work, but toggle bolts would be even stronger. You didn't mention if you own or rent, so that might affect you being able to cut into it.