Gunsmith Extractor O' Ring 10 - Pack. Extractor O' Ring AR15 is designed to go over the bolt extractor spring, typically on short barreled applications to help with extractor reliability. In need of a high-quality .223/5.56 extractor O' ring for your AR? Look no further than Luth-AR's .223/5.56 extractor O' ring. This O' ring is designed specifically for use with .223 caliber and 5.56 caliber ARs and is made from durable, high-quality materials. The Extractor O' Ring s designed to go over the bolt extractor spring, typically on short barreled applications to help with extractor reliability, ensuring that your AR operates smoothly a Mfg: Luth-Ar