I hope resurrecting an old post is better than creating a new one with the same topice.
I, like many others, have been dissatisfied with the sheath that comes with the Becker BK-7, due to it's loose fit and rattling. Six years ago, I bought a Chestnut Ridge Kydex sheath for it and was also dissatisfied with it - my belt barely fits through the loop, it rides too high for a backpack, it's difficult to draw quietly and it's uncomfortable to sit while wearing.
I devised a way to hang the Kydex upside down from the right side of an Uncle Mike's vertical shoulder holster for a left-handed cross draw, but I couldn't figure out a way to angle the handle forward slightly, so it was hard to reach; I felt like I might slash my right thigh when drawing; and, though it was great for a right-handed reverse grip draw, the Kydex was rattling against the snap on the holster as well as the zipper of the pocket on the backpack hip strap - thus, defeating the whole purpose. Also, I decided a layered system would be preferable, anyway - with the blade on my hip, like normal, if I take the backpack off, I still have the revolver and blade; if I take the gun off, I still have the blade on my pants belt.
So, I went back to the original holster - which I like better anyway, other than the rattle - and attempted to fix it, using the vast wisdom of the internet. I tried a blow dryer, an iron and a pot of boiling water in order to squish that plastic insert into a better fit. The only result was the insert started to crack and the nylon began to wear and warp. I tried stuffing a strip of cardboard in there. At first I though, 'Great; problem solved; simple, free solution. I should've just done that in the first place.' Then I thought, 'What if it gets wet?' Regardless, after a few insertions and drawings, the cardboard became stuffed all the way in and it was in the way and I couldn't get it out. I tried pulling the plastic insert out, using two pairs of pliers. Nope.
At this point, my curiosity (and, perhaps, my frustration) got the better of me and I slit the nylon open to see what the hell was going on in there. I don't know if this is true on all of them, but on mine, the inserts are stitched in, so they don't come out without ruining the sheath.
So, now what? Do I buy the same dumb sheath for $18 and try to glue a piece of inner tube in there (more internet wisdom)? Do I spend $60 on the Spec Ops Combat Master when the reviews say a BK-7 doesn't fit snug in there without modification? Do I buy a leather sheath that costs twice as much as the knife and is going to suck if it gets wet? For now, I'm stuck with the Kydex and will have to remove it whenever I need to sit, and it's difficult to get on and off due to the loop being too small.
Any advice would be greatly appreciated. Thanks.
Kydex isn't that spendy, and that way you can decide what you want and sell the other. I am partial to kydex myself, but a nice leather sheath is sexy. From what I've seen, godspeed and azwelke make awesome kydex, and skystorm has got good hide. Whatever you decide to get, we need pics 
the more versatile the better...
