This design features a longer internal transition taper into the choke constriction, making the overall length of this tube longer than the original Mobilchoke tube.īarrels that use the Optima-Choke will typically be marked OB immediately adjacent to the gauge marking.
Barrels marked with the "OB" stamp will use the Optima-Choke system. The Optima barrels can be identified by locating the letters “OB” stamped next to the barrel gauge stamp. This new barrel utilized a larger internal bore dimension known to some as “back-boring” and required a new choke tube design to give the proper constrictions. In the year 2000 Beretta introduced the 12-gauge Optima Bore barrel design into some of our competition shotguns. The major diameter of the choke tube thread is 20.62 mm (.811 inch). The length of the threaded portion is a nominal 9.15 mm (.360 inch). The start of the threaded portion of the 12 gauge Mobilchoke tube is located a nominal 41.5 mm (1.63 inch) from the breech end of the choke tube. If the choke tube is steel shot compatible it will also be marked SP . Mobilchoke choke tubes will be marked PB or ST and the degree of choke. 410 tubes, identification is very much self evident.īarrels that use the Mobilchoke will typically be marked only with the gauge marking.
While the dimensions noted will vary for the 20, 28 gauge and. The following pertains specifically to 12 gauge Mobilchoke tubes. The conical parallel design of the Beretta choke tubes creates a more gradual taper inside the choke tube which gently transitions into a parallel section that runs to the muzzle end of the tube. The conical parallel design results in reduced shot deformation, improved pattern uniformity and increased pattern density.
#LEFEVER NITRO SPECIAL 12 GAUGE BARREL CHOKE SERIES#
The Mobilchoke system continues to be the mainstay of the 680 series field grade over and under shotguns and the A300 Outlander semi automatic shotgun. At this time the Mobilechoke is the only choke tube system adapted by Beretta to 12, 20, 28 gauge and. Introduced in the mid 1980's the Mobilchoke tube system was first available for the model S687L over and under and later carried through virtually every model of fixed breech and semi-automatic shotgun. How can I tell which choke tubes fit in my shotgun?
0 kommentar(er)
