Hi folks, I just mounted a MOE SL-K on my newest franken-15.  How do I utilize the footmans loop?  I do not feel like paying for the magpul QD M-lok adapter.  What do I need to make a sling work like this photo?

Thanks!

In for a better answer, but it looks like an Oval Slider or ITW Tri-Glide of the right width might work (on the opposite side of the stock, which is hidden in the photo you posted).

I use a couple tri-glides on an old B5 SOPMOD to accomplish that. Run the sling through, run through tri-glide, the end goes back through the stock, then is locked to the rest of the sling with another tri-glide.

Here's my regular M4 stock with my sling mounted the same way as your picture, I've got a standard model Vickers VCAS foliage green 2 point sling.

I just use a tri-glide at the back of the stock (left side), which can't be seen, it's optional you could also use another tri-glide at the right side of the stock to prevent the sling from sliding to the left.

Usually slings will come with two tri-glide at the rear of sling but you'll have to buy another tri-glide if you want an optional tri-glide at the right side of the stock.