Why did U. S. Senator Edward Kennedy fight to save the M14 in 1963? In a word, jobs. According to the November 1963 issue of Guns & Ammo page 57,
"Counter pressures have been aroused and aired for many months concerning hints of the possible demise of the M14. An influential trio of Massachusetts legislators paid a call to Defense Secretary McNamara to plead for new orders last winter when Harrington & Richardson, Inc., Worcester, Mass., one of the M14's three manufacturers, received word that its present order would be the last. The members of the this delegation were House Speaker McCormack, Senator Ted Kennedy, who has promised to "do more for Massachusetts," and Senator Saltonstall, Senate Armed Service Committee ranking Republican. They departed empty-handed."
The following contains all of the subcontractors I've been able to identify to date in my research. All of the subcontractors to Harrington & Richardson Arms (Worcester, MA) have been identified and are listed below.
Company / Subcontractor to / Known parts made or support rendered as a subcontractor
20th Century Manufacturing (Chicago, IL)Harrington & Richardson
A & M Tool and Die Co., Inc. (Southbridge, MA)Harrington & Richardson
A. A. Brunell Electroplating (Worcester, MA)Harrington & Richardson
Aber Machine & Tool Corp. (East Templeton, MA)Harrington & Richardson
Allied Manufacturing Co., Inc. (Worcester, MA)Harrington & Richardsontooling support
American Twist Drill Company (Detroit, MI)Harrington & Richardson
American Walnut (Kansas City, KS)Harrington & Richardson
Associated Engineers (Springfield, MA)Harrington & Richardson
Atwood Vacuum Machine Co. (Rockford, IL)Springfield Armorymagazine
B. F. Goodrich Co. (Watertown, MA)Harrington & Richardson
Bay State Tool & Machine (Springfield, MA)Harrington & Richardson
Bemis & Call (Springfield, MA)Harrington & Richardson
Bird & Sons (Walpole, MA)Harrington & Richardson
Birken Manufacturing Co. (Hartford, CT)Harrington & Richardson
Booker & Wallestad (Minneapolis, MN)Harrington & Richardson
Borg-Warner (Rockford, IL)Olin Mathieson Chemical Corporation Springfield Armorymagazine
Bostich (East Greenwich, RI)Harrington & Richardsonunknown parts
Botwink Brothers (Worcester, MA)Harrington & Richardson
Bristol Spring Manufacturing Co. (Plainville, CT)Harrington & Richardson
Brookfield Machine & Tool (West Brookfield, MA)Harrington & Richardsontooling support
Brown & Sharpe Manufacturing Co. (Providence, RI)Harrington & Richardson
Bruce Machine and Engineering (Peabody, MA)Springfield Armorywindage knob
Brunswick Sports Products Co. (Torrington, CT)Olin Mathieson Chemical Corporationmagazine
Casting Engineers (Chicago, IL)Harrington & Richardson
Chandler & Farquhar Company (Boston, MA)Harrington & Richardson
Chemical Corporation (Springfield, MA)Harrington & Richardson
Chenard Machine (Worcester, MA)Harrington & Richardson
Cincinnati Milling (Cincinnati, OH)Harrington & Richardson
Conetta Manufacturing Co. Inc. (Stamford, CT)Harrington & Richardson
Continental Screw Company (New Bedford, MA)Harrington & Richardson
CPPSpringfield ArmoryNM windage knob
Dearborn Gage (Garden City, MI)Harrington & Richardson
Detroit Broach & Machine (Rochester, MI)Harrington & Richardson
Dougherty Tool Co. (Southboro, MA)Harrington & Richardsonunknown parts
Dunbar Brothers (a division of Associated Spring Corp.) (Bristol, CT)Harrington & Richardson
Eagle Tool (Iron Mountain, MI)Harrington & Richardson
Eastern Machine & Tool Co. (Worcester, MA)Harrington & Richardsontooling support
Elastic Stop Nut (Union, NJ)Harrington & Richardson
Elbro Tool Co., Inc. (Cherry Valley, MA)Harrington & Richardsontooling support
Excell-o Corporation (Greenville, OH)Harrington & Richardson
Falls Machine Screw Co. (Chicopee, MA)Harrington & Richardson
Federal Products Corp. (Providence, RI)Harrington & Richardson
G. E. Prentice Company (Kensington, CT)Harrington & Richardson
General Tire & Rubber Co. (Marion, IN)Harrington & Richardsonfiberglass stock
George F. Blake (Worcester, MA)Harrington & Richardson
Granger Contracting Company (Worcester, MA)Harrington & Richardson
Greenfield Tap & Die (Greenfield, MA)Harrington & Richardson
H. Sack & Sons (Brookline, MA)Harrington & Richardson
Hartford Gage Co. (West Hartford, CT)Harrington & Richardson
Hartford Machine Screw Co. (Hartford, CT)Harrington & Richardson
Hesse Machine & Mfg. Co., Inc. (Boston, MA)Harrington & Richardsonunknown parts
Hesse Machine & Mfg. Co., Inc. (Boston, MA)Olin Mathieson Chemical Corporationmagazine latch
Heywood-Wakefield Co. (Gardner, MA)Harrington & Richardsonunknown parts
Hoppe Tool (Springfield, MA)Harrington & Richardson
Hurley Manufacturing Company (New Hartford, CT)Harrington & Richardson
Ikonen Tool & Die Co. (Templeton, MA)Harrington & Richardson
Illinois Tool Works (Chicago, IL)Harrington & Richardson
Industrial Research (Holyoke, MA)Harrington & Richardson
John Bath Co. (Worcester, MA)Harrington & Richardsontooling support
Jones & Lamson Machine Co. (Springfield, VT)Harrington & Richardson
Kennametal, Inc. (Windsor Locks, CT)Harrington & Richardson
Killeen Machine & Tool Co. (Worcester, MA)Apex Metal Stamping, Springfield Armory, Harrington & Richardsonmagazine for Apex Metal Stamping and Springfield Armory, magazine and butt plate assembly for Harrington & Richardson
Kingsbury Machine Tool Corp. (Keene, NH)Harrington & Richardson
Krueger-Barnes Corp. (Detroit, MI)Harrington & Richardson
La Pointe Machine Tool Co. (Hudson, MA)Harrington & Richardson
Leesona Corp. (Providence, RI)Harrington & Richardson
Letts Drop Forge (Detroit, MI)Harrington & Richardson
Lundquist Tool & Mfg. Co. (Worcester, MA)Harrington & Richardson Olin Mathieson Chemical Corporationoperating rod spring guide
Manchester Tool & Design (Manchester, CT)Harrington & Richardson
Massachusetts Steel Treat (Worcester, MA)Harrington & Richardson
Mechanical Components CorporationCraft Metal Corporationgas cylinder
Mercury Tool & Machine (Aston, PA) Rock Island Arsenal operating rod
Michigan Machine & Broach (Detroit, MI)Harrington & Richardson
Middlesex Paper Tube (Lowell, MA)Harrington & Richardson
Millbury Engineering Co. Inc. (Millbury, MA)Harrington & Richardsonunknown parts and tooling support
Mite Corporation (New Haven, CT)Harrington & Richardson
Moore Drop Forge Co. (Springfield, MA)Harrington & Richardson
Morrow Manufacturing Company (North Kingston, RI)Harrington & Richardson
Morse Twist Drill (New Bedford, MA)Harrington & Richardson
MXRSpringfield Armory, possibly Olin Mathieson Chemical Corporationsafety
National Rivet & Manufacturing Co. (Waupun, WI)Harrington & Richardson
North Machinery Sales (South Boston, MA)Harrington & Richardson
Ober Tool & Die Company, Inc. (Everett, MA)Harrington & Richardson
Olson Manufacturing Co. (Worcester, MA)Harrington & Richardson
P & O Machine Co. (Brockton, MA)Harrington & Richardson
Packaging Service (Agawam, MA)Harrington & Richardson
Perry Packaging (Boston, MA)Harrington & Richardson
Pilot Company (Hartford, CT)Harrington & Richardson
Pioneer Tool Co. (West Springfield, MA)Harrington & Richardson
Pratt & Whitney Co. (West Hartford, CT)Harrington & Richardson
Precision Products (Chicopee, MA)Harrington & Richardson
Rathbone Corporation (Palmer, MA)Harrington & Richardson
Rhode Island Tool Co. (Providence, RI)Harrington & Richardson
Rochester Manufacturing Company (Rochester, NY)Harrington & Richardson Springfield Armorymagazine
S. E. Overton Co. (South Haven, MI)TRWwood stock
Saco-Lowell (Saco, ME)Springfield Armory, Harrington & Richardsongas cylinder
Scoville Manufacturing Co. (Waterbury, CT)Harrington & Richardson
Sheffield Corporation (Dayton, OH)Harrington & Richardson
Sime Control Company (Chicago, IL)Harrington & Richardson
Simonds Machine Company (Southbridge, MA)Harrington & Richardson
Southern Gage (Erin, TN)Harrington & Richardson
Southern Screw Company (Statesville, NC)Harrington & Richardson
Stanley Industrial Components (Forestville, CT)Harrington & Richardson
Stanley-Humason (Forestville, CT)Olin Mathieson Chemical Corporationfront band, safety spring
Star Gage Company (Springfield, MA)Harrington & Richardson
Sterling Sales (North Grafton, MA)Harrington & Richardson
Storms Drop Forging Co. (Springfield, MA)Harrington & Richardsonreceiver and other part forgings
Swank, Inc. (Attleboro, MA) Olin Mathieson Chemcical Corporation selector lock
Sykes ManufacturingSpringfield Armorywood stock
Textile Machine Works (Reading, PA)Harrington & Richardsonbolt
The Connecticut Spring Corp. (Farmington, CT)Harrington & Richardson
The Franklin Screw Machine Co. (Hartford, CT)Harrington & Richardson
The Hanson & Whitney Co. (Hartford, CT)Harrington & Richardson
The Torrington Company (Torrington, CT)Harrington & Richardsongas cylinder
Thomas Smith Co. (Worcester, MA)Harrington & Richardson
Triple X Sales (Westboro, MA)Harrington & Richardson
Union Hardware Company (Los Angeles, CA)Springfield Armory, Olin Mathieson Chemical Corporationmagazine
Union Twist Drill Co. (Athol, MA)Harrington & Richardson
United Engineers, Inc. (Springfield, MA)Harrington & Richardson
Unity Machine & Tool (Philadelphia, PA)Harrington & Richardson
Varsity Manufacturing Co. (West Springfield, MA)Harrington & Richardson
W. J. Shannon Trucking Co. (Worcester, MA)Harrington & Richardson
Wachusett Corrugated Corp. (Worcester, MA)Harrington & Richardson
Waltham Precision Instrument (Waltham, MA)Harrington & Richardson
Westfield Gage Co. (Westfield, MA)Harrington & Richardson
Westinghouse Electric (East Springfield, MA)Harrington & Richardson, Olin Mathieson Chemical Corporationmagazine
Wetzel Tool Co. (East Hartford, CT)Harrington & Richardson
Wico Electric Co. (a division of Eltra Corp.) (West Springfield, MA)Harrington & Richardson, TRWelevation knob
Worcester Tool & Die Co., Inc. (Worcester, MA)Harrington & Richardsontooling support
Wright Manufacturing Co. (Worcester, MA)Harrington & Richardson, TRWwindage knob
Additional References: 1) Gauthier, Joseph H. "Arms Company Boosts Shipments." The Evening Gazette (Worcester, MA) June 22, 1961. 2) Harrington & Richardson, Inc. First Northeast Commerce and Industry Exposition brochure.