The following tabulation lists the tolerances recommended by the Investment Casting Institute; however, the technical ability of Ruger Investment Casting is growing so rapidly that we present an extension of the list as a guide for larger configurations. Always keep in mind that your specific configuration is the most important criteria in determining dimensional variation from part to part during production. By actively seeking our advice, much can be done to achieve more stringent tolerances than those listed.

Linear Tolerances
Length Dimensions	Normal	Premium
Up to 1/2"	+/-.007"	+/-.003"
1/2" to 1"	+/-.010"	+/-.005"
1" to 2"	+/-.013"	+/-.008"
2" to 3"	+/-.016"	+/-.010"
3" to 4"	+/-.019"	+/-.012"
4" to 5"	+/-.022"	+/-.014"
5" to 6"	+/-.025"	+/-.015"
6" to 7"	+/-.028"	+/-.016"
7" to 8"	+/-.031"	+/-.017"
8" to 9"	+/-.034"	+/-.018"
9" to 10"	+/-.037"	+/-.019"

For maximum cost effectiveness specify plus or minus .010" up to 1", and plus or minus .005" per inch thereafter. To avoid additional cost we recommend that configurations maintain a minimum .060 wall thickness.

Hole Tolerances - The tolerances for holes are: up to .500" diameter, plus or minus .005"; over .500" diameter to 1.000" diameter, plus or minus .010"; over 1.00" diameter, add an additional plus or minus .005" per inch or fraction thereof. These specifications apply to "D" holes as well as round holes.