Wilson Combat match barrels are fully machined from aircraft grade stainless steel forgings and heat-treated to R/C 40 for maximum service life. Critical manufacturing tolerances are held to less than .0005" (one half thousandth of an inch). All barrels are slightly oversized in the lock-up areas and require pistolsmith fitting. Ramped barrels are recommended in alloy frame pistols for maximum reliability. All ramped barrels are ramped for Wilson cut unless otherwise specified.