Manual

Chamber lengths are identified by the numeral 70 or 76. The
numeral 76 designates a chamber length of 76mm which is equal
to the English measurement of 3 inches. A barrel marked with
the numeral 70 designates a chamber length of 70mm which is
equal to the English measurement of 2
3
/
4
inches.
Use of shotgun shotshells with lengths shorter than the shotgun
chamber length is acceptable. However, never use shotshells
with chamber lengths greater than the length of the shotgun
chamber. For example, do not use 3 inch shells in a shotgun
chambered for 2
3
/
4
inch ammunition.
Chokes are identified for each barrel below the designation for
gauge and chamber length on the underside of the barrels. Choke
designation indicates the dispersion pattern characteristics of the
shotgun bore. The following chart provides identification for
choke and a pattern percentage of shot pellets within a 30 inch
circle at specified ranges.
Choke
Identification Description Percentage Distance
1/1 Full Choke 70 - 75 35m
3/4 Improved 65 - 70 35m
Modified Choke
1/2 Modified Choke 60 -65 35m
1/4 Quarter Choke 55 - 60 35m
VZ Improved 45 - 50 35m
Cylinder Choke
S Skeet 70 - 75 20m
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