Re: 16-18 inch shorty rifles
The DTA Covert height (sitting flat) is ~6 1/4" (w/o optic) and ~9 1/2" (w optic). Of course, that will increase depending on how high the bipod and rear monopod are set.
Don't know the width for sure, never tried to measure it.
Lengths are as follows 16" barrel: ~29 1/2"; 22" barrel: 35 1/2". This is a little longer than the DTA values because I have the muzzle brakes installed. This could be shortened up a bit by removing one or more of the buttpad spacers, but I'm comfortable with them in and therefore haven't had a good reason to remove them.
Here's a pic comparing the Covert with the 16" barrel to a Sig 556 pistol (10.5" barrel w <span style="text-decoration: underline">no</span> stock, <span style="font-style: italic">at left</span>), and with the 22" barrel to a Sig 556 SWAT (16" barrel w M4 folding stock, <span style="font-style: italic">at right</span>). Sorry, the ruler is a little hard to see.