The U.S. Carbine Caliber .30
- Infrared - Snooperscope & Sniperscope Model M1

Infrared Background & Overview Sniperscope & Snooperscope Model M1 Sniperscope Model M2 (Early & Late) Sniperscope Set No. 1, 20k volts Model M3 Metascopes Select an image to view the web page Sniperscope & Snooperscope Model M1 Development Production Deployment Part II: Production Background The Snooperscope and Sniperscope were still undergoing development when the first directive was received to proceed with limited procurement. Consequently, the design had to be accomplished simultaneously with production. Additionally, the final design that normally preceded production would not be approved until service tests had vetted the design. Production had started before the service tests and ended the same month the tests were completed. [1] Efforts to obtain a prime contractor for the complete Snooperscope and Sniperscope who could complete production within the time required were unsuccessful. To expedite production, Electronic Laboratories Inc. of Indianapolis was selected for the master contracts for the completed Snooperscopes and Sniperscopes but furnished only some of the items. The telescopes and several other critical items were procured by the Engineer Board and provided to Electronic Laboratories as government-furnished equipment. Procured by the Engineer Board Item Contract Manufacturer Telescope Ordnance Dept. Sperry Gyroscope Corporation of Brooklyn, NY Carbine & ring mounts Ordnance Dept. Inland Division of General Motors, Dayton, OH Pistol belt and suspenders Quartermasters Corps regulation general issue Engine generator Engineer Corps Atlas Aircraft Products of New York, NY Provided by Electronic Laboratories Item Manufacturer Power Supply Electronic Laboratories Infrared Lamp C.M. Hall Lamp Co. of Detroit, MI Battery Assembly Electronic Laboratories Charging Rack Electronic Laboratories Snooperscope Handle Bassick Mfg Co. (Alemite) of Chicago, IL Carrying Cases unknown The design, drawings, and contracting the manufacture of the telescope were handled by the Ordnance Department at Frankford Arsenal. The Engineer Board assisted with the electronic components. Ordnance designated the telescope as Telescope, Model T-120 (Experimental, Sniper's Telescope). This designation would not change until sometime after the service tests were completed and a final design was adopted [2] [3]. Drawings of the other components and specifications for the complete equipment of the final production models were prepared by the Engineer Board. The need to divide the responsibility for procurement of the various components for the Sniperscope and Snooperscope caused production delays. Electronic Laboratories was founded in Indianapolis in 1932 by William Garstang and Norman Kevers for the manufacture of vibrator power supplies and other electronics-related equipment. Their first location was a 10,000 sq. foot warehouse at 122 West New York St., Indianapolis. By the end of WWII, their assembly plant was located across the street at 309 North Illinois Street. Warehousing, packaging, and shipping were located a mile north at 803 North Senate Avenue. Their main manufacturing plant had been relocated to 24th and Meridian streets, 2 miles north of their New York St. facility. [4] Just before Christmas 1943 William Garstang, President of Electronic Labs, was made aware of the possibility of a government contract from the Corps of Engineers. He immediately traveled to Washington D.C., where he met with Captain Ricker of the Engineer Corps at the Statler Hotel. Garstang was presented with the details of what the contract would require. Garstang returned to Indianapolis with brief sketches of the proposed parts and met with Walter Peek (Vice-President of Sales), Bill Otto (Chief Electronic Engineer), and Raul Frye (Vice-President of Engineering). It was decided they would take on the project. At the time Norman R. Kevers was Chairman of the Board with Harry C. May as the Vice-President of manufacturing. Electronic Labs was subsequently issued contract E.B.P.O. No. 44-009-ENG-105 for $705,000 on December 17, 1943, for the production of 715 Sniperscope sets, 1420 Snooperscopes sets, 215 battery charging racks, spare parts, and related equipment. [5] During the weeks that followed Garstang traveled to RCA Labs in Princeton, NJ, for meetings with Dr. George A. Morton (RCA Research Scientist and member of the National Defense Research Committee on night vision), Frankford Arsenal regarding the optical design of the telescope, and Polaroid in Massachusetts regarding infrared filters. He also traveled to the Engineer laboratories at Ft. Belvoir with handmade models to determine their acceptability [6]. Garstang later related Electronic Labs engineers had designed: the power supply that converted 6 volts DC from a non-spillable storage battery to the high voltage required for the operation of the electronic telescope methods of charging storage batteries in the jungle from any source of power that might be available the light source having the correct beam pattern to adequately flood a combat area With all equipment designed to withstand: moisture along with the conditions native to a jungle environment fungus and small mites that would destroy even an aluminum casting the shock of gunfire Production was underway when the Infantry Board trials of the previously described prototypes began on 23 Feb 1944. The Infantry Board had been provided with a production light assembly for use in the trials [7]. A summarized list of WWII contract records [5] indicates Electronics Labs completed production in April 1944. Shortly after completion of the Infantry Board trials of the prototypes. Garstang indicated the cost per unit was approximately $1200 each including the T3 carbine [6]. The cost of the T3 carbines was approximately $35 each. The history of Electronic Laboratories and their involvement with infrared Snooperscopes and Sniperscopes will continue with the pages devoted to the Model M2 Sniperscope. The Snooperscope & Sniperscope Procurement had separated the Snooperscope from the Sniperscope as two separate items. The only difference was the manner in which their T-120 telescope and light assembly were mounted. All equipment but the hand mount, carbine mount, and carry bags were identical and interchangeable. Snooperscope Total Weight: 21 lb. 5 1/2 oz Sniperscope Held in the viewing position. Total Weight without carbine: 26 lb. 13 oz. Performance of the Production Models A number of the deficiencies encountered with the prototype models were overcome with the production models. The Objective lens no longer loosened during firing Light beam distribution was corrected to illuminate only what the telescope was pointed at, no more An increase in radiation from the light source and infrared filter improved their performance within the 35-yard effective range Weatherproof - Exposure of the equipment to a tropical downpour did not affect performance - water seals did not fail As with the experimental models, under the best of conditions, enemy troops in the prone position could be seen at ranges greater than 200 feet. Kneeling silhouettes could be readily seen and identified at ranges up to 200 feet in open terrain. Silhouettes at ranges of 300 feet or more were too indistinct to identify. Vehicle reflectors could be seen at 400 yards. These ranges were approximate only and subject to weather conditions. In a real-world environment, the effective range was considered to be 35 yards. Concealment afforded by trees, bushes, and underbrush effectively screened personnel because the infrared light was reflected from vegetation with such intensity that objects or persons behind it were not readily seen when using a single device. Movements of foliage by concealed troops was, however, easily detected. Cross illumination was effective in reducing glare from vegetation. When an infrared light was shone at about right angles to the line of sight of a telescope viewer, objects or persons hidden in brush appeared as brighter objects against a darker background. It was recommended whenever possible the Sniperscopes and Snooperscopes should be used in pairs to overcome the interference from foliage and take advantage of the benefits of right angle illumination. The Manual     TM 5-9340 consisting of 174 pages was published 01 Sep 1944. It served the purpose of both a user manual and a technical field manual for both the Sniperscope and Snooperscope. Nine pages are devoted to an appendix with instructions for use of the Type US/C-1 Infrared Viewer. An additional ten-page appendix is devoted to instructions for use of the Type US/F Metascope. The manual includes a detailed list of parts and manufacturers for the Sniperscope and Snooperscope. It has a fair amount of duplication as both used many of the same parts. It was the most detailed manual of any of the infrared scope manuals that would eventually follow. Photographs used in the manual were those available at the time the manual was constructed. A few of the photographs show prototype parts versus the final production designs. These photographs and minor mistakes in the narrative were normal for manuals authored before all of the production model information was available to the authors. A copy was included with each Sniperscope set and each Snooperscope set. The Model T-120 Telescope Research, development, and design of optical components for the Army (telescopes, periscopes, binoculars, etc.) were the responsibility of the Ordnance Department Fire Control Sub-Office at Frankford Arsenal [3]. This office designed and developed the telescope for the Sniperscope and Snooperscope. The Technical Staff of the Engineer Board assisted with the design of the electronic and mechanical components. The final design was designated by Ordnance as the Telescope, Model T-120. Ordnance prepared the drawings then contracted Sperry Gyroscope Company for their production [1] [8]. The T-120 telescopes were provided to Electronic Laboratories as government furnished equipment for inclusion in the assemblies of the M-1 Snooperscope and M-1 Sniperscope. The Sperry Gyroscope Company was originally organized in New York on April 14, 1910, by electrical inventor Elmer Ambrose Sperry for the purpose of manufacturing and marketing his ship gyro-stabilizer, gyro-compass, and high-intensity searchlight. By the 1930's and 1940's, Sperry Gyroscope worked with Stanford and MIT to develop the microwave technology that was necessary for modern radar systems. During the Second World War, the company grew more than tenfold as it produced computer-controlled and stabilized bombsights for the B-17 and B-32 bombers, automatic pilots, fire control systems, airborne radar equipment, and automated take-off-and-landing systems. [9] Specifications   Focus Range: 4 feet to infinity Length: 12 1/2" Diameter: 2 3/4" Weight: 3 lb. 9 oz. Serial Numbers: 1 - 2135* [10]   * unknown if spare bodies had serial numbers The design of the telescope provided for a watertight unit by internal pressure which tested 7.5 lb. per square inch. The waterproof condition was maintained during movement by the objective lens and eyepiece being sealed to a brass hydraulic bellows manufactured by Clifford Manufacturing Co. of Boston, MA. Click on the image to open an enlarged version in a new window The Objective Lens Assembly Objective Lens Dimensions Length: 3 3/4" extended   3 1/4" retracted Diameter: 2 3/4" The lens cap used with the T-120 Telescopes was a semi-transparent light brown pliable plastic. The canvas strap connected to a grommet in the center of the lens cap. TM 5-9340 Sniperscope and Snooperscope (01 Sep 1945) indicates the lens cap was made of leather. This information appears to have preceded the final design for production. The objective lens filter was a sheet of a cellophane type material manufactured by the Polaroid Corp. The Body Assembly Reticle Assembly (left & center) Cushion (right) The V in the reticle (above) was inverted by the image tube (below). The point of aim was the apex of the inverted V The tube body was approximately 5.48" in length. The outside diameter, front and rear, where the scope rings attached was approximately 1.9". Inside diameter was approximately 1.78". The scope rings were designed and manufactured by the Inland Division of General Motors in Dayton, OH. As part of their Ordnance contract for the Model T3 carbine. The foot on the bottom of the front ring was inserted into the opening above the front of the receiver. The rear ring was secured in place between the azimuth adjustment screws at the rear of the scope mount. Windage adjustment of the scope was accomplished by loosening the azimuth adjustment screws and moving the rear of the scope left or right. Then secured by tightening the azimuth adjustment screws. The plate and thumb screw on the side of the stock secured and supported the power cable. Model 1P25A Infrared Image Tube manufactured by Farnsworth Length specifications were 4 7/16" +/- 1/8". The manufacturing process that produced the image tubes produced an overall length that varied up to 1/4". The shorter tubes required the addition of a spacer ring inside the eyepiece assembly to secure them in place (see Eyepiece Assembly below). TM 5-9340 indicates image tubes were "designated as short or long tubes according to whether they are less than or greater than the normal length of the tubes". The tubes do not have markings indicating this designation. Tube socket manufactured by Cinch Manufacturing Co. Front - Rear (Numbers on the rear of the socket indicate which pin on the image tube the connector supplies power to.) View into the rear of the scope with the eyepiece assembly removed showing the image tube (center) within the Tube socket with the power cables attached. Desiccator Assembly & Compression Spring Spring tension as the eyepiece was attached pressed the desiccator assembly forward against the rear of the tube socket. Forcing the image tube forward against the reticle. The size of the hole in the center of the desiccator prevented it from coming in contact with the image tube. The Eyepiece Assembly Variations in tube length (as much as 1/4") caused by their manufacturing process required the use of the Separator with the longer tubes, to increase the distance between the eye lens and image tube. The separator was not needed with the shorter tubes. Army Technical Manual TM 5-9340 dated 1 Sep 1944, shows three different rubber eye shields. The tapered one above with two convolutions. Seen here in a photograph taken during training in Burma during February 1945. A different tapered one with three convolutions in the three pics of a Sniperscope/Snooperscope being held by the soldier. The third shown is depicted in the Ordnance drawings of the Telescope T120. Initially dated November 1943, it was revised four times with the last revision being August 1944. Seen here and on all of the remaining T-120 scopes people have shared information on so far. The threads to mount the eyepiece are just forward of the nameplate. The first ring behind the nameplate locks/unlocks the focus ring behind it for focus adjustment. The rubber eye shield is secured to the eyepiece using the clamp ring. Focus  Objective Lens:  Rotation of the knurled ring focused the image on the front of the image tube  Electrostatic (Image Tube):  The focus was fine tuned by rotating the Power Pack Potentiometer Knob  to change the voltage inside the image tube.  Ocular Lens (Eyepiece):  Rotation of the ring nearest to the rubber eyeshield focused the image from  the image tube for the operator's eyes. The Ocular focus was then locked  in place by tightening the locking ring.  Objective Lens:  The only adjustment thereafter was done using the objective lens for various  distances, followed by fine tuning the electrostatic focus. Nameplates were attached to the Ocular Lens Assembly and designed to be removable. Nameplates were probably initially applied to only the scopes that passed final inspection. Its possible name plates were transferred to a replacement Ocular Lens Assembly if the original became unusable. Some of the scopes later sold as surplus were absent their nameplates. Light Source Assembly (Model X-264) The Model X-264 Light Assembly was used with both the Snooperscope and Sniperscope. The only difference was their mounts. Manufactured by the C.M. Hall Lamp Co. of Detroit, MI, under a subcontract issued by Electronic Laboratories. Specifications   Light Beam: 16'-20' wide x 8'-10' high @ 120' Length: 3 1/2" Diameter: 5 7/8" Weight: 1 lb. 3 1/2 oz. Removal of the Clamping Ring allowed the Filter/Gasket and Reflector/Socket to be removed from the Light Source Bracket without removing the light assembly from its handheld or stock mount. The diameter of the filter was approximately 5 15/64" with minor variances due to the nature of the manufacture of the glass. The rubber gasket was cemented to the filter to protect against moisture and/or visible light leaks. Replacement of the filter necessitated the replacement of both the filter and the gasket (Filter Assembly). The filter & gasket were manufactured by the Polaroid Corporation of Cambridge, MA. The glass was optical quality "Water White" anti-reflective and heat-resistant glass. The coating that allowed infrared light to pass while blocking visible light consisted of four layers of Polaroid XR7X-type cellophane film (3 blue-dyed, 1 red-dyed). The infrared light spectrum that passed through the filter was 9,000 - 11,500nm. The coating was applied to only one side of the glass and protected from the elements and use by mounting the filter with the uncoated side facing outward and identified with the words "This Side Out". Visible light could not be detected by anyone not looking directly into the light beam. Looking directly into the beam on a moonless night visible light could be detected from about 20 feet.[1] A-1529 was the filter part number. N-677 was the gasket part number. The meaning of the etched letter and numbers is unknown. The residue on the edge of the filter was an overflow of the adhesive used to attach the gasket to the filter. Exposure to the heat emitted by the bulb eventually caused the bond of the cellophane film to loosen. The normal operating life of the filter was approximately 25 hours (also the approximate lifespan of the bulb). Severe operating conditions could shorten the lifespan further. The cable from the grip switch that operated the light connected to the receptacle on the rear of the light. L-1581 was the Bracket part number. A-1581 was the Clamping Ring part number. The cable socket was attached to the rear of the reflector using two rivets. A-1567 was the Reflector part number. The reflector surface was gold plated due to gold's high infrared reflectivity. Bent or damaged reflectors could distort the light beam. Bulb Specifications Model: GE 1045 Designation: P15s30 Type: Incandescent Miniature Lamp Volts: 5.9 Amps: 5 Watts: 29.5 Mount: Flanged/Bayonet Lifespan: 25-30 hours* * fingerprints on the glass and/or severe    operating conditions could shorten the lifespan The beam emitted by the bulb was pre-focused by the manufacturer by adjusting the position of the flange up/down on the brass body. The flange was then soldered in place to hold the focus. Bulb operation could be verified without disassembly by feeling for heat emitted through the filter. Light Mounts The Snooperscope and Sniperscope light mounts were cast aluminum coated with a flat black finish. The plastic handles with the orange marbled appearance were made of Bakelite. Black plastic handles have been observed on M1 Snooperscopes and Sniperscopes but may have been replacements instead of originals. Snooperscope Mount Specifications Length: 9" Height: 9 1/2" Thickness: 1 1/4" Weight: 1 lb. The light switch was a simple momentary on/off switch. Depressing the switch activated the light. When the switch was released, the light went off. To keep the light on required constant finger pressure on the switch. The light assembly was secured to the frame using the thumbscrew on the front and a screw on each side of the frame (blue arrows). The yellowish cable clamps were made of soft plastic. The original Snooperscope light mount was absent support for the power cable. Support was later added to some of the original Snooperscope mounts (blue arrow) after the introduction of the M2 Sniperscope. The Snooperscope Telescope Mount The telescope mount was attached to the frame of the Snooperscope Mount using two screws. The one at the front from underneath. The one at the rear from the top. The Azimuth Screws at the rear of the telescope mount were used for windage adjustment and securing the scope to the mount. Telescope Mounts for the Model M1 Snooperscope appear to have been made of cast brass but possibly bronze. The Snooperscope as a separate unit from the Sniperscope was discontinued with the introduction of the Model M2 Sniperscope. It was replaced by including a handheld mount as an accessory to the M2 Sniperscope. Sniperscope Mount Specifications Length: 6 1/2" Height: 5 1/2" Thickness: 1 1/4" Weight: 10 1/2 oz. The Light Assembly attached to the Sniperscope mount in the same manner as it attached to the Snooperscope mount. Secured to the mount by a single screw on each side of the mount and the thumbscrew at the front. The trigger on the front of the handgrip activated the light. Depressing the trigger activated the light. When the trigger was released, the light went off. To keep the light on required constant finger pressure on the switch. The Sniperscope Stock Mount The Sniperscope power cable was supported by a cable clamp attached to the left side of the stock. The light switch cable from the power cable was secured to the left side of the stock. The mount was attached to the stock using 4 binding head screws. Each with a washer and internal lock washer. Refer to the web page on the Model T3 carbine for further information on the T3 stock. Sniperscope & Snooperscope Model M1   The Production story continues with the ... Power Supply - Power Cable - Battery - Charging Cable Charging Rack - Carry Bags - Suspenders/Belt Tools - Maintenance/Repair Kits     Click Here   References [1] "Report 908, Snooperscope and Sniperscope, Project XR 441", 30 Jan 1945, Capt. Edmund R. Ricker, Corps of Engineers,       Fort Belvoir, Virginia [2] Army Ordnance Telescopes Report, Fire Control Sub-Office, Frankford Arsenal, Philadelphia, PA, 5 Sept 1944 [3] The Ordnance Department: Procurement and Supply, by Thomson & Mayo, Center of Military History Washington D.C., 1960 [4] Indianapolis Industries, The Indianapolis News, 21 Mar 1946 [5] Alphabetic Listing of Major War Supply Contracts, Cumulative, June 1940 through September 1945, Civilian Production       Administration, Industrial Statistics Division, 1946 [6] E-L Breaks Story of SS Equipment The Electronic Beacon, Electronic Laboratories employee newsletter, April 1946 [7] Infantry Board Report #1595, Fort Benning, GA, 20 Apr 1944 [8] TM 5-9340 Snooperscope and Sniperscope, 1 Sep 1944 [9] Sperry Gyroscope Company Division records, Hagley Museum and Library, Wilmington, DE 19807 [10] TM 5-9341 Operation & Maintenance Instructions for Sniperscopes, Models M1 & M2, Aug 1951 Credits Many different people have contributed to make these web pages on the Model M1 Snooperscope & Sniperscope possible. Thank you, everyone. We'd like to especially acknowledge the following individuals whose contributions have been significant. In alphabetical order: Marc Beaudry,   Rick Larson,   William Morris,   Jason Patrick (Historian's Office, U.S. Army Engineer School), Marcus Rust,   John Spangler,   Andrew Stolinski (Archival Research Group),   Eric Nicolaus (Nicolaus Associates) Online Resources Articles   Infrared Forum The Newsworthy section of our forum has a number of different articles that include various articles on the infrared scopes and equipment used with the .30 cal. Carbines. Go to the Articles In addition to providing a means to communicate with other owners and those of us doing the research, there are short articles on the various aspects of the infrared equipment. Also, several posts on the ongoing research showing contract numbers, dates, quantities, serial number blocks, and more are updated as additional information becomes known. © Copyright 2012- The Carbine Collectors Club. All Rights Reserved.