The Apex Grade Threaded Semi Drop-In 4.25" Barrel is designed for the 9mm Smith & Wesson M&P. Due to the tolerance variations in the M&P Slide" the barrel is semi drop-in. In some cases" this means the barrel may drop-in without alteration" but in most cases will likely require minor fitting which is easily done by the end user. The stainless steel barrel features a 1:10" twist rate. The design increases accuracy performance making the M&P capable of shooting as small as a 1-1/2 inch grouping at 25 yards. Accuracy test results based on use of a mechanical rest. Final results may vary based on shooter ability" ammunition selection and variations in factory firearm tolerances.
Due to variations in factory slide tolerances, slight fitting may be required and is easily performed by the end user