Barrel system for a firearm

A barrel assembly for a firearm, comprising:

• a barrel comprising:
• a follower lug extending downward from an underside of a rear portion of the barrel proximate to a front portion of the barrel, the follower lug including a notch in a bottom portion of a front face of the follower lug, wherein the notch includes a vertical face facing frontwards and a horizontal face facing downwards;
• and
• a rear lug extending downward from the underside of the rear portion distal to the front portion of the barrel such that a recess groove is formed between the follower lug and the rear lug, the rear lug including a generally horizontal bottom surface configured to be supported by a generally horizontal surface of an upper projection of a locking block of the firearm while in a locked position and during an initial recoil period, wherein the locking block is secured to and is stationary with respect to a frame of the firearm and is configured to lock the barrel to a slide of the firearm prior to firing, the barrel further configured such that during the initial recoil period the rear lug generally horizontal surface slides rearward along the horizontal surface of the upper projection of the locking block such that downward movement of the barrel is prevented, whereby the barrel starts to angle downward when the follower lug contacts the upper projection of the locking block, the barrel further configured such that further rearward travel of the barrel with respect to the frame is arrested by contact between the recess groove and the horizontal surface of the upper projection;
• and
• a takedown lever mechanically cooperated with the barrel and the locking block of the firearm, the takedown lever including a cylindrical pin rotationally coupled to the locking block.