How the heck to you take the Defiance stock off the tube on the Kriss CRB? I'm not talking about the tube itself, I mean the stock ... on an AR, you simply pull the lever down on the collapsible stock and slide the stock off the tube. But on the Kriss Defiance stock, the lever doesn't seem to be able to be pulled down, and I don't want to force it.

Is there a trick to sliding it off the tube? The stock is kind of big and I'd like to replace it with a Magpul MOE carbine stock.

Also, does anyone know if the tube on the Kriss is commercial diameter or Mil-spec? Thanks in advance; I can't find the info I seek on the Kriss site.

For anyone interested, Kriss has informed me of the following:

"The Defiance stock comes off just like any other M4 stock. You may notice that there are two tabs toward the front of the lever that are there to help you get more leverage when lifting the lever." So I'll give it another try tonight.

Also, the tube on the Kriss CRB is Mil-Spec diameter.