The new 9mm Apex Grade Semi Drop-In or Gunsmith Fit replacement barrels for the M&P are available in either 4.25" or 5.00" versions.
Apex conducted extensive accuracy testing using a mechanical rest to eliminate the human factor and gauge how accurate the barrels are when only the mechanical factors of the pistol are in play. What we found are 5-shot groupings at 25 yards that are routinely in the sub one inch range with 115gr., 124gr. and 147gr. factory ammo. Of course, this is from a rest so final results may vary based on shooter ability, ammunition selection and variations in factory firearm tolerances.
The Mk 1 Apex Grade Semi Drop-In 4.25" & 5" 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.
4.25-Inch - $289.99
5-Inch - $289.99