the shroud i there i gues for fitting a diopter front sight job; the barrel oring actially pushes the barrel upwards from its free floating position so once removed ot touches the inner bottom edge of the shroud.
ive shot mine a number of times now with the shroud off completely and its performance is incredible fpr what they cost secondhand. id not have paid mew prices for one but im very pleased with it s/hand . the biggest thing i suppose is if your accurate enough to notice the poi shift.....
instead of cutting the shroud right back as il be hfting and even hunting with mine will be a suport inside the shroud between it and the cylinder. and also a full length hamster similar to the walther hunter?? ones but probly milled ally.