Make it a screen entity. From the manual (search for type):

ENTITY* shotgun_onscreen =
{

x = 100; // 100 quants in front of camera
y = -20; // to the right
z = -20; // below

type = "shotgun.mdl";
flags = SHOW;// visible on screen from the start
view = camera; // same camera parameters as the default view
}

It does not react on level lightning, though.