Why is it important to know the barrel length of my FIREARM?
To get the correct holster model fit, you need to know the barrel length of your gun. It’s important to know that even on the same compact handgun, such as the M&P 2.0 9mm, its possible to have a couple of different barrel lengths.
One reason to check the barrel length is that some holsters have closed bottoms, and if the length of the barrel is not measured correctly it won’t fit the holster.
For light-bearing holsters, most use a muzzle plug for stability and retention issues (e.g. duty holsters with and without a light). Without the stability of the muzzle plug, the holster will not have retention, either with or without the light. The muzzle plug fits to specific barrel lengths, and will not work with threaded barrels under the standard manufacturer’s barrel length. Further, if the holster/gun fit is not correct, the barrel will not fit up to the plug, or it will not fit in the holster at all if the plug is too tall.
A third reason to know the gun’s measurements is that ALS levers are designed to fit the different barrel lengths. For example, a 4.25” M&P may not use the same ALS lever as a 5” M&P model, depending on the version/caliber/etc.
HOW TO MEASURE BARREL LENGTH
PISTOL
Pistol barrel length is measured from the back portion of the ejection port to the end of the barrel.
Gun barrel lengths are measured in Imperial standard.
REVOLVER
Revolver barrel length is measured from the face of the cylinder to the end of the barrel. Gun barrel lengths are measured in Imperial standard.
Most modern revolver barrels have lugs beneath the barrels. This is an extension that may run the length of the barrel that encloses the ejection rod. Check your model designation at the manufacturer’s website if you have questions about the length of your gun’s barrel or barrel lug as both can affect holster fit.
COMPETITION PISTOL
Competition pistol barrel length is measured from the back portion of the ejection port to the end of the compensator.
Gun barrel lengths are measured in Imperial standard.