HELP ME! Jumping position

Okay so the deal is: when I jump, my WHOLE body slides back in the saddle. Picture someone holding their position, but it just sliiiiiides back (NOT my leg! My WHOLE body)

So I've been trying different things to fix it.. Lowering the fences, TONS AND TONS AND TONS AND TONS of stirrupless (sitting trot, sitting canter, posting trot, 2-point trot, 2-point canter, and LOTS of it), etc. Obviously the stirrupless helps (when does it not?) but the only thing it does is ensure that my leg doesn't slide back behind my body. But my whole body still slides back..? I've also tried ONLY thinking about it when I'm jumping, like gripping for life with my calf so that I don't slide. But I still do?

Here's a picture. I purposely tried to get the worst picture I could, and this was from about 3 months ago, so I've improved a LOT since then (I only go EVER so slightly back now!) but I want to make it go away all-together!

Any tips? Ideas? Has anyone else had this problem?
**Once again, this is NOT an issue with my leg sliding back, but rather my whole body!

By the way:
Please don't critique the picture, critique what I said in the post! I already know that I wasn't gripping enough in the picture, the point of the pic was to show what I meant by "whole body sliding back"

If it wasn't for you're sliding back, I'd say you have a decent position.

Is it possible your stirrups are too long. It doesn't look like you're able to sink you weight into your heels.

Wow, good one. I've never seen anything like that. Saddle looks to be in the right place. I have no clue why you're ending up 4" behind it when jumping. Have you tried other saddles to see if it's just a freak saddle fit thing?

Thank you! :)
And thanks for the suggestion, too! I'm about to go outside and jump, so any suggestions are really appreciated! :)

It could be your saddle. Does it truely fit you correctly?

The saddle you choose, must be the perfect one. Think of it like....how Harry Potter found the "perfect" wand for him...I know, weird analogy but it's what popped in my head....so work with me.....

The saddle you choose, must not only fit your horse well, but you also. It must AID your position. It must HELP you solidify your position well and easily. It must HELP you - not hinder you. It must be the perfect match.

Sounds to me, and it is only an assumption since I cannot see you in this saddle at all, or see pictures of you in it - is that since you have put so much effort into fixing this 1 issue, with on success....that the saddle is hindering you, not aiding you.

I personaly don't think it is you.........I think it is the saddle.

Actually, I JUST bought a new saddle haha!
The picture above is with my old saddle.

My new saddle fits both myself and my horse perfectly, and its SO comfortable. It's helped a ton with keeping me up front instead of sliding. But I still slide back about an inch or so.

If it wasn't the saddle, does anyone have any other suggestions? :/

It almost looks like you are being left behind....possibility

You guys! I just jumped today and my leg was near perfect! :)

(But we only jumped about 3ft so it was nothing too challenging)

Here are 2 pictures. As you can see my core is a little more forward than I would like it, but I was mostly concentrating on #1: DISTANCES, and #2: not sliding back.

Now that the sliding problem is solved, I can FINALLY start focusing on things like my release and stuff!


****Please say any critiques or suggestions now!****
I'm very open to crit. Obviously, I already know that in these pictures I need more of a release, and for my core to be farther back. But go ahead and tell me more if you'd like! Or good excercises to fix the above.

And if anyone knows of a good way to see distances, let me know!!! I have so much trouble!

Your feet are still fairly flat in the stirrup....push your heels down.

Your release is actually pretty good. You arent catching him in the mouth or have droppy reins. Maybe an inch or two further up. What I don't like is your arched/hollowed back, but it kind of looks like that is your natural position and not forced.

Distances: The only way to be able to see them is to do them. Have your coach tell you what a line should ride in. Get it in that many. Then lengthen and shorten. Ride straight and bending lines, knowing and not knowing what the line is to ride in. Count out loud! The whole line. Count to singles as well. If you think the jump is 5 strides out, start counting out loud from 5 and see if you are right or wrong. Chipping in or leaving long means you should have held your horse or moved them up.