Our standard barrel contours are based on those used by Stevens for their single shot rifles and are similar to those used by Winchester and other single shot manufacturers. We contour barrels in house and can usually accommodate special requests, though there may be an extra charge.
Shank: At the breech end we will leave a shank 1" in diameter 1.25" long unless you request something different
Round/Octagon Barrel Contours - Straight taper from the breech to muzzle
Part Octagon Barrel Contours - Our part octagon barrels have no taper on the octagon section which is approximately 11" long. There is a slight step to the round section which tapers to the muzzle
Barrel Breech Approx. Muzzle
Size Diameter Diameter
#1* 0.875" 0.79"
#2 1.00” 0.91"
#2½ 1.03” 0.95"
#3 1.065” 0.97"
#4 1.135” 1.04"
#5 1.185” 1.10" Depending on barrel manufacturer, may finish smaller
#6 1.25” 1.17" Available in round contours only, may finish smaller
*Most rifles have a thread size larger than .875" so you will need a special flute at the rear to give you enough shoulder to fit the barrel to the frame
CPA Finished Barrel Contours
The picture below shows the standard forearm length and hole spacing for our CPA and Stevens 44 1/2 barrels with the standard 2-screw forearm.