Sig Sauer P322 Features The new P322 was completely designed and built by SIG SAUER in New Hampshire and is loaded with premium features, including an optic-ready removable rear sight plate so you can easily add a ROMEOZero red dot optic without the use of adapter plates. The Sig Sauer P322 also comes with a threaded barrel adapter making it suppressor ready right out of the box, and with its ambidextrous controls, interchangeable flat and curved triggers, and fiber optic front and rear sights the new P322 Sig is the highest capacity, most advanced 22 caliber pistol in its class.