Due to the required bolt weight, blowback designs in pistols are generally limited to calibers smaller than 9×19mm Parabellum (e.g., .25 ACP, .32 ACP, .380 ACP, 9×18mm Makarov, etc.) There are exceptions such as the simple blowback pistols from Hi-Point Firearms which include models chambered in .45 ACP, .40 S&W, .380 ACP and 9×19mm Parabellum. Simple blowback operation can also be found in small-bore (such as .22LR) semi-automatic rifles, carbines and submachine guns. Most simple blowback rifles are chambered for the .22 Long Rifle cartridge. Popular examples include the Marlin Model 60 and the Ruger 10/22. Most blowback carbines and submachine guns are chambered for pistol cartridges such as the 9×19mm Parabellum, .40 S&W and .45 ACP. Examples include the MP 40, Sten and UZI. The bolt can be made bigger and more massive in these weapons than in handguns, as they are intrinsically heavier and designed, ideally at least, to be fired with both hands, often with the aid of a shoulder stock; and these factors help to ameliorate the disruption to the shooter's aim caused by the heavy bolt's movement. Consequently, simple blowback is adequate for somewhat more powerful rounds in submachine guns than in standard pistols. There were also a few rifles that chambered cartridges specifically designed for blowback operation. Examples include the Winchester Model 1905, 1907 and 1910. The only known assault rifle to use simple blowback was the Burton Model 1917.