Mosin Sling Loop ( Dog Collar ) length

I just acquired a bunch of Russian & Finnish slings, & there is one odd dog collar that was all alone that stood out from the rest.
This one is over a foot long compared to the normal length of eight to nine inches. ( No obscene jokes please )
What is the sling loop length for the early M28 dual slot, ski-trooper stock?
Would twelve & one half inches be long enough to secure the sling on this model?

Thanks to Vic's Guide to Com-bloc slings, I was able to ID the 1942 or 43 SVT-40 sling in the bunch. The sling pictured in his article with the blued buckles & web body is identical to the one I just bought for $5.00