BudsGunShop.com - Barrel Profile?

Eve, this rifle has a "Carbon Steel medium profile barrel. Barrel heat up will depend on your rate of fire between shots.

Eve - This rifle has a medium barrel profile. The barrel is made of carbon steel. The M&P15-22 SPORT features a 10-inch M&P slim handguard that incorporates the popular Magpul M-LOK™ system. The M-LOK system allows rifle owners to easily customize their M&P15-22 SPORT by adding accessories without removing the handguard. M&P15-22 SPORT owners have the option of easily mounting numerous M-LOK-compatible accessories or any number of Picatinny-style rail sections designed to accommodate other accessories. Smith & Wesson includes a 2-inch M-LOK rail panel with each rifle. The M&P15-22 SPORT comes standard with one of the most popular folding sights systems available for MSRs. The removable Magpul MBUS® front and rear folding sights are lightweight and durable, further enhancing the performance and value of the new M&P15-22 SPORT. As far as the barrel heating up, barrels begin to heat up with the first shot fired. How much they heat up depends on the individual shooters rate of fire. Since this is a .22, one could overheat the barrel, but that is not a real concern. with reasonable use. The pressure of 22LR is much less than .223, for example, and won't heat up nearly as much as the center fire cartridges.