http://en.wikipedia.org/wiki/Ruger_10/22

http://www.ruger.com/products/1022/index.html

http://www.ruger1022.com/

https://www.gmriflebarrel.com/

http://www.ruger1022.com/docs/israeli_sniper.htm

http://www.gunblast.com/Ruger-1022.htm

http://www.impactguns.com/store/ruger_rimfire_rifles.html

http://www.gmriflebarrel.com/catalog.aspx?catid=10-22.920sporterdiameterbarrels

http://www.hornetproducts.com/bin/category.asp?category=1

http://www.shootersxchange.com/ruger_rifles.cfm

http://www.impactguns.com/store/736676011032.html

http://www.ehow.com/how_4469522_custom-ruger-rim-fire-rifle.html