The Carbine Collectors Club

Click on the image above to learn more about the M1 Carbine

Forum Home Forum Home > The Club > Infrared Scopes and Equipment, Night Vision
  New Posts New Posts
  FAQ FAQ  Forum Search   Register Register  Login Login

Sniperscope, M3. Development 1945-1950

 Post Reply Post Reply
sleeplessnashadow View Drop Down
Admin Group
Admin Group

Joined: Nov 09 2015
Location: SoCal
Status: Offline
Points: 1151
Post Options Post Options   Thanks (2) Thanks(2)   Quote sleeplessnashadow Quote  Post ReplyReply Direct Link To This Post Topic: Sniperscope, M3. Development 1945-1950
    Posted: Jun 15 2019 at 3:28pm

Printable PDF


Sniperscope, M3 

Development 1945-1950


Prototypes Manufactured by

Hillyer Engineering

New York, NY


Jim Mock

Production of the first infrared Model M2 Sniperscopes was underway when the U.S. Army Corps of Engineers implemented a research project for the development of the infrared Model M3 Sniperscope on 12 Jun 1945 (1). The first shipment of the M2 Sniperscopes to the Engineers was expected to be by 01 Aug 1945 (2).    

The surrender of Japan 02 Sep 1945 resulted in immediate cancellation of many military contracts. The companies affected halted all current production and/or future plans. This ended all .30 cal. carbine related production in progress at both Winchester and Inland Manufacturing. It is not known if the contracts with Bell & Howell and Electronic Laboratories for the Model M2 Sniperscope were also canceled. This is the subject of ongoing research.

The impact on the various ongoing military research and development projects was an immediate halt to many of the projects until future funding could be determined. This included the research laboratories of the Corps of Engineers working on the development and improvement of various infrared devices.

The War Department Equipment Board restarted the research and development of infrared equipment that included the Sniperscope, M3 in May 1946 due to a requirement for a more effective night viewing device (3)

Research has located a number of quarterly progress reports prepared by the Research and Development Laboratory of the Army Corps of Engineers at Ft. Belvoir, VA between 1947 and 1953. It appears the reports were first instituted with a 01 Jan 1947 report that presents a synopsis of the status of various projects as opposed to quarterly activity (1). The quarterly reports that followed weren’t always quarterly in addition to some quarters apparently not present in the location the documents were found.

The status of the project for the Sniperscope, M3 as of 01 Jan 1947 was 30% of the research and development on the image tube and the optical system had been completed with an anticipated project completion date of 30 Jun 1949. The objective and ocular lens system were under development by the University of Rochester, NY. On completion of the optical design, a procurement description of the M3 Sniperscope would be prepared and issued for contract bids.

Contract for Twenty-Four Service Test Sniperscopes, M3; Spring 1947

The next progress report located is dated 01 Jul 1947. It indicates a contract was awarded to Hillyer Engineering Company of New York, NY for the fabrication of 22 Sniperscopes, M3 for service tests. The sniperscope would include a 17,000 volt image tube and optical components explicitly designed for infrared efficiency. The anticipated range was expected to be double that of the M2 Sniperscope with a 1.5 increase in resolution and a much brighter image. An Engineer Steering Committee meeting 07 Nov 1947 identified the Hillyer contract number as W-44-009-ENG-484 for the fabrication of 24 Sniperscopes, M3 with no reference to a quantity of 22. (4)

The Hillyer Engineering Company was founded in 1945 by Curtis Hillyer. Within a year of receiving the contract for the Sniperscope, M3 the company name was changed to Hillyer Instrument Company. They were a relatively small laboratory specializing in the research and development of optical photoelectric equipment along with infrared radiation and detection apparatus. In 1946 the company consisted of Curtis Hillyer, three physicists, 4 engineers, 5 technical personnel and 3 additional personnel for a total staff of 16 personnel. (5)

Hillyer had previously worked for Fairfield Engine and Airplane Company on the research and development of the Felix infrared guided missile. His research physicists included Eugene Coleman who came to Hillyer from the RCA research laboratory and John Sweer who came to Hillyer from the U.S. Navy Ordnance Laboratory and left Hillyer in 1950 to work for RCA in their research laboratory.

By 01 Jul 1947, a contract had also been awarded to Chatham Electronics of Newark, NJ for a thorough study of high voltage supplies operating from a 6 volt and 24-volt power sources with the view of obtaining the most compact, lightweight and reliable equipment. Chatham Electronics was a research laboratory offering consultant services with electronic tubes, equipment, and circuits. (6)

Technical difficulties with the Model M3 Sniperscope’s prototype image tube Type C-7128 being developed by RCA delayed the progress of the project in late 1947 and 1948. Hillyer Instrument Co. completed the construction of the telescope and power supply by 30 Sep 1948. An improved image tube Type C-7128A had been developed with 24 of the tubes delivered to Hillyer Instruments by 31 Dec 1948.

First of Twenty Four Received: March 1949

The first of the 24 Sniperscopes, M3 was delivered by Hillyer Instruments to the Engineers by 31 Mar 1949. This progress report included the photocopies of photographs of Hillyer’s first Sniperscope, M3.

Hillyer Instruments Company

First production R&D Sniperscope, M3

Project 2187, Infantry Board No. 3, Fort Benning, GA; April 1949

This first Hillyer scope was submitted to the Infantry Board at Fort Benning, GA, for an Accelerated Service Test. The results of the tests are presented in the Infantry Board Report 2187, dated 06 May 1949. The performance of this unit was determined to be superior to the Model M2 Sniperscope, but the unit was not yet suitable for full field trials. A number of modifications were recommended, with the most significant issues involving the failure of the image tubes due to shock. This was caused, in part, by the design of the image tube but more so by the high voltage insulation within the scope. Additional service tests were recommended after the modifications had been completed.

Contract for Twenty-Four M3 Sniperscopes Completed, Modifications Begin; June 1949

The Hillyer Instruments contract was completed with the delivery of the remaining 23 Sniperscopes, M3 with drawings to the Engineers by 30 Jun 1949.

To address the results of the Infantry Board tests, the Engineer Research and Development Laboratory initiated a number of different modifications to the design. Four of the Hillyer M3 Sniperscopes were selected to incorporate all of the modifications.

The issues with the high voltage insulation for the image tube and associated divider required a better method of connecting the high voltage cable from the power pack to the image tube. The Engineer R&D lab began work on a “potted” socket containing a portion of the 400-megohm voltage divider, a glass window to enclose the high voltage end of the tube and the terminals for making connections to the rheostat used to vary the focusing voltage. The divider resistors and connections, the socket for insertion of the high voltage lead, and the outer portion of the glass window would be encased in a Dow Corning potting resin for additional insulation.

Modifications included a better method of mounting the telescope body on its base to prevent failures to fire, a method of locking the objective assembly to prevent drifting while firing, a reticle projection system modified to make the horizontal and vertical adjustments independent of one another and provide a more satisfactory means of making adjustments.

During the same time period, RCA was contracted to make improvements in the C7128A image tube including improvement of its resistance to shock. The Ordnance Department was requested to conduct tests to determine the type and intensity of the various shocks to which the tube was subjected when the carbine was fired.

Project 2187A, Infantry Board No. 3, Fort Benning, GA; March 1950

The Infantry Board at Ft. Benning received the four Hillyer Sniperscopes, M3 (Modified) for testing on 16 Mar 1950. All of the modifications had been completed on these four scopes with the exception of the failure rate of the image tubes. Research and development to correct the image tube failures were still in progress, so additional image tubes were included to ensure the tests could be completed.

Infantry Board Project 2187A Partial Report dated 11 Apr 1950 details the tests conducted. Included is a brief overview of the equipment along with photographs.

Physical Characteristics


Carbine                                                                         5 lbs 8 oz.

Telescope including cable                                            4 lbs 9 oz

Infrared projector including switch                              1 lb 6 oz

Power Pack                                                                   4 lbs 7 oz

Battery & Case                                                             11 lbs 8 oz

Flash Hider                                                                   5 oz

Belt, suspenders, knapsack                                           2 lbs 6 oz

Complete Sniperscope including unloaded carbine     30 lbs 1 oz


Telescope, barrel diameter x length                              2 ½” x 13 ¾”

Cable, diameter x length                                               7/16” x 50”

Power Pack                                                                   8 3/8” x 5 5/8” x 3 3/8

Battery                                                                          8 5/8” x 7 5/8” x 2 ¾”

Knapsack                                                                      12” x 9” x 3 ¾”

Infrared projector, diameter x length                            5 7/8” x 3 ½”

The chest was made of steel. The knapsack was modified from the canvas knapsack used with the battery and power supply of the M2 Sniperscope made during WWII.

With the exception of the addition of the lamp switch, the Light Assembly was the Light Assembly of the T120/M1 Snooperscope, Sniperscope and M2 Sniperscope. The Light Assembly mount was incorporated into the design of the scope body.

Adjustment of the reticle horizontally and vertically was accomplished by removing the reticle assembly cap. Elevation of the light beam was adjusted by rotating an offset concentric bolt.

The three power leads were the High Voltage lead to the image tube, a 6-volt lead to the Light Assembly and a 6 volt lead to the Reticle Assembly. The Objective lens was not removed for the photographs.

The battery was the standard three-cell 6-volt battery used for the T120/M1 Snooperscope, Sniperscope and M2 Sniperscope. The power supply was clamped to the battery as with the previous power supplies.

As with the earlier power supplies, the cable was affixed to contacts inside the power pack requiring disassembly to remove the cable. The cable high voltage lead slid into the high voltage socket when the lid was attached to the power supply. Above, it is barely visible lying on top of one of the rectifier tube covers. The transformer was covered with silver foil.

The Tests Conducted by the Infantry Board as Requested by the Corps of


Test #




Whether or not modifications recommended in report of Project 2187 have been made

All 7 recommendations modified and no longer an issue


The ease of zeroing the test item to the carbine

Constant & varied difficulties maintaining the scopes in operable condition prevented completion of test.

Tests that were conducted showed zeroing easily obtained at 75 yards in daylight and darkness with groups in the center of the 10” bullseye.

Test subjects unanimously preferred the M3 Sniperscope due to its adjustable reticle over the M2 Sniperscope non-adjustable reticle.


The maximum viewing range of the equipment under varying conditions of temperature, weather and visibility

Partial test only due to failure of M3 Sniperscopes

Silhouette: scopes ranged from barely visible to very clear at 125 yards, all barely distinguishable at 150 yards

Cotton O.D.: Very clear at 125 yards, barely distinguishable at 150 yards

HBT Fatigue: Clear at 125 yards, barely visible to not visible at 150 yards

M2 Sniperscopes were less clear and limited to 75 yards.


The maximum effective night firing range on the carbine, equipped with the test item, under varying conditions of temperature, weather and visibility

Tests not completed due to constant M3 Sniperscope malfunctions.

Training familiarization before tests showed accurate fire and hits at 125 yards. M2 Sniperscope failed to get hits beyond 75 yards.


The effectiveness of the equipment in night reconnaissance and night movement

Tests not completed due to constant M3 Sniperscope malfunctions.

Training familiarization before tests showed operators could locate and identify targets much more rapidly than with M2 Sniperscope


The light security of the M3 Sniperscope

Both M2 & M3 Sniperscope lights:

Indirect angle light undetectable until 3’

Direct beam dull red seen at 30’


The overall ease of operation and maintenance in the field and the durability of the equipment

Power switch and electrostatic focus rheostat easily accessible with location on M3 Sniperscope. Much preferred over rheostat with rubber cover on M2 Sniperscope power pack.

Better image resolution of M3 Sniperscope made it easier to adjust and operate than M2 Sniperscope.

(Deficiencies noted included in full list below)


If there is a requirement for a monopod for use with the equipment

All preferred use with locally fabricated monopod as holding equipment over extended periods was less tiresome. Especially when standing to see over tall grass.

Monopod designed by personnel of the Infantry Board

Discontinuation of Tests

Tests could not be completed as all four Sniperscopes became inoperable. A technician provided by the Engineer Research and Development Laboratory was unable to maintain the units due to the types of problems encountered.

Of the 18 deficiencies indicated in the report, most were minor modifications involving various parts and screws that needed to be secured better. Two were deficiencies that plagued the infrared scopes and equipment throughout their history: the weight and acid leaking from the batteries. Six deficiencies alone or in combination were responsible for the early termination of the tests with damage that could not be repaired onsite.



Suggested Modification

Image tube not sufficiently durable

Flashes occur from the shock of firing, any damage is permanent

Make the tube more durable

Vibrator not sufficiently durable

Too frequent failure of operation of high voltage power supply

Provide more durable vibrator

Vibrator leads poorly insulated

Low voltage grounds frequently occur when reassembling power pack

Redesign terminals to prevent shorting out

Solder connection on wire terminals on rheostat and vibrator

Difficult and time consuming to replace parts; requires special equipment

Provide spade-type lug connections (or some other more desirable method)

Resistors are soldered in reticle assembly and rheostat

Break frequently during disassembly; difficult to replace; requires special equipment

Eliminate resistors, or redesign method of installation

The cable between the power supply and telescope not rigid enough

Failure of operation of the unit

Make cable more durable

Test Conclusions

The Sniperscopes, M3 (Modified) were returned for further development, with particular attention to the correction of the deficiencies. After the deficiencies were  corrected, it was requested 4 Sniperscopes, M3 (Modified) be returned to the Infantry Board for further user tests.

It’s important to keep in mind the infrared image tube, high voltage power supply, and the sniperscope they were part of were new technology in the process of being developed. The Infantry Board tests and reports were part of the research and development to perfect the technology.

Back to the Drawing Board 

An Engineer R&D progress report dated 30 Jun 1950 indicates the four Sniperscopes, M3 (Modified) were undergoing the requested modifications. Springfield Armory had completed the image tube shock tests and was planning tests of a prototype shock mount. RCA was continuing their efforts to improve the shock resistance of the image tube. Contracts for further development of the high voltage power supply were being negotiated.

The Hillyer Instrument Company Infrared Sniperscope, M3 Passes into History

Changes in funding priorities brought on by the outbreak and ongoing activities of war have historically done more for technology and the efforts of its research and development than any peacetime in history. Often with benefits that exceed the duration of the war and the military. Such was the case with infrared research after the invasion of South Korea by North Korea on 25 Jun 1950.

On 31 Aug 1950, the Chicago Procurement Office granted a development procurement contract for the design and improvement of the Sniperscope, M3 to the American Optical Company (7). Unlike the Hillyer Instrument Company, the American Optical Company possessed the resources not only for research and development but also for full-scale production in quantity.

American Optical designed and submitted their first pilot model by September 1950. The success of the pilot model resulted in production approval in November 1950 and the designation of the sniperscope and it’s equipment as Sniperscope, Infrared, Set No. 1, 20000 Volts. The initial quantity of 1,000 was increased to 6,000 (7).

Many of the features present in the design manufactured by Hillyer Instruments were included and improved by American Optical in the design of their Model M3 Sniperscope. Many of the features in the design of the power supplies manufactured by Hillyer can be found in the power supplies manufactured by Oak Manufacturing for the Model M3 Sniperscopes in the Sniperscope, Infrared, Set No. 1, 20000 Volts.

The disposition of the 24 Model M3 Sniperscopes manufactured by Hillyer Instruments has not been found in the records located to date.

Hillyer Instrument Company Infrared Sniperscope, M3, Serial Number 5

In early 2019 a dealer obtained this scope with its power supply from an individual in the Indianapolis area. The individual who sold it to the dealer provided no information to its history from 1950-2019.

The Hillyer scope is now in the Dan Pinto collection. The photographs that follow were taken by the author with permission.







To be continued...

The history of the Model M3 Sniperscope along with the Sniperscope, Infrared, Set No. 1, 20000 Volts, as manufactured by American Optical and later Capehart-Farnsworth will be presented in the future on the website of


1) 01 Jan 1947 Quarterly Progress Report on Research & Development by the Engineer Research & Development Laboratories

2) “Infra-Red Devices, Developed by the Engineer Board, Corps of Engineers, Status as of July 1945” Scientific Research and Experiment Department, Admiralty (Great Britain)

3) Partial Report of Test of Sniperscope M3, Project 2187, Army Field Forces Board No. 3, Ft. Benning, GA dated 6 May 1949

4) Communication from Engineer Research and Development Laboratories, Ft. Belvoir, VA to Commanding General, Army Ground Forces, Ft. Monroe, VA 02 Jan 1948, subject Sniperscope M-3

5) Industrial Research Laboratories of the United States, Eighth Edition, 1946, published by the National Research Council, National Academy of Sciences, Washington D.C.

6) Industrial Research Laboratories of the United States, Ninth Edition, 1950, published by the National Research Council, National Academy of Sciences, Washington D.C.

7) 31 Dec 1950 Quarterly Progress Report on Research & Development by the Engineer Research & Development Laboratories

Archives Research Assistance provided by Andrew Stolinski Archival Research Group New Market, MD

The Carbine Collectors Club Copyright© 2019

This article and/or it's images are the property of the author. They're not to be copied without prior written permission (Title 17, Chapter 5, Section 501(a) U.S. Code)

Edited by New2brass - Jun 19 2019 at 9:51pm
Back to Top
jackp1028 View Drop Down
Hard Corps
Hard Corps

Joined: Jan 01 2016
Location: Cloudcroft, NM
Status: Offline
Points: 1262
Post Options Post Options   Thanks (0) Thanks(0)   Quote jackp1028 Quote  Post ReplyReply Direct Link To This Post Posted: Jun 16 2019 at 4:27pm
Dan & Jim, Great article! A couple of questions:

1) Dan, is your Sniperscope operational?

2) If so, is it possible to post an image of what the user sees through the scope to understand the capability of the technology at the time? Compare to contemporary night vision scopes.

3) Is it possible to show the relative difference in image quality between the Bell and Howell (M2) and Hillyer (M3) Sniperscopes to understand the level of improvement achieved?

4) The caution on the battery pack refers to recharging and vehicle connections. Was the Sniperscope ever intended to also be vehicle mounted, possibly for nighttime surveillance use rather than sniping?

Again, great article. I appreciate the effort you guys put into this.
Back to Top
W5USMC View Drop Down
Moderator Group
Moderator Group

Joined: Apr 29 2017
Location: Missouri
Status: Offline
Points: 2925
Post Options Post Options   Thanks (0) Thanks(0)   Quote W5USMC Quote  Post ReplyReply Direct Link To This Post Posted: Jun 17 2019 at 11:59am
Agree with JackP, great article and outstanding research. Thanks for posting.
USMC Retired
NRA Life Member
Back to Top
m1a1fan View Drop Down
Hard Corps
Hard Corps
Got Para?

Joined: Jan 01 2016
Location: Virginia
Status: Offline
Points: 1736
Post Options Post Options   Thanks (0) Thanks(0)   Quote m1a1fan Quote  Post ReplyReply Direct Link To This Post Posted: Jun 17 2019 at 4:39pm
Jim and Dan,

Awesome article. Well thought out, researched and presented. Really appreciate the effort and the share. 
Back to Top
sleeplessnashadow View Drop Down
Admin Group
Admin Group

Joined: Nov 09 2015
Location: SoCal
Status: Offline
Points: 1151
Post Options Post Options   Thanks (0) Thanks(0)   Quote sleeplessnashadow Quote  Post ReplyReply Direct Link To This Post Posted: Jun 17 2019 at 10:25pm

The Hillyer Dan has wasn't operational due to a lack of maintenance for so long. Dan's cleaning connections and running tests to see if it is operational.

There are two elements as to what can be seen thru a particular IR scope. One is the image tube, the other is the optics. The difference between what is seen with a 1P25 image tube (T120/M1 Snooperscope & Sniperscope, M2 Sniperscope) and the 6032 image tube (M3 Sniperscope) is the distance things can be seen. The optics of these Sniperscope/Snooperscope models were pretty much the same as far as clarity.

Everything I've found on the image tube used with the Hillyer indicates it's either real close or equal to the 6032 image tube. The difference indicated as the 6032 being more durable when it came to taking shock from firing.

Getting a pic that accurately depicts what one sees when looking thru these scopes is a bit of a challenge. At some point we'll be working on the best setup for getting pics.

So the improvement of what one would see with the Hillyer versus the M2 Sniperscope was the distance things could be seen and the distance they could be seen clearly enough to identify. The M2 scopes were roughly 35-50 yards for clarity and 75-100 yards for "still visible" but not identifiable. The Hillyer and M3 scopes were roughly 65-80 yards with clarity and 125 yards for "still visible" but not identifiable. What a person was wearing made a slight difference in how far away they could be seen clearly. As did humidity and atmosphere.

All of the above is from the documents. What the documents did not mention is the 1P25 image tube does not see visible light. The 6032 image tube does. Which makes a difference with the various amounts of visible light present down range.

From personal experience with working M3 Sniperscopes the center of the image is clearer than the extreme outer perimeter. Distance with no visible light using the IR light on the scope is about 70-80 yards for identifying something. The light puts out a beam like a spotlight. Using a modern day IR light of greater power helps a little with distance but more so with the clarity of things within that 70 yard distance. If the beam is wider the scope sees more and clearer off to the sides. Keep in mind anything blocking a spotlight will also block an IR light. Like tree limbs and bushes.

We know of no efforts to mount any of these sniperscopes on a fixed position, jeep or otherwise. The idea was they needed to be mobile just like the carbine was. Able to move in every direction with the carbines they were on for scanning and rapid target acquisition. Keep in mind the distance they worked best at and the use of a beam as opposed to a flood light.

The powered IR scopes used by the Navy could be handheld but their design and purpose was for signaling as opposed to clarity. Often with a need to be left on for extended periods of time and monitored. Because of this each had a means for them to be mounted to a 12" Navy spotlight using an adapter. In addition to the self powered DC IR viewers the Navy also had an AC 115v version of each powered IR viewer. After WWII the AC 115v versions were the Navy standard. With DC power being optional if the viewer was even designed for DC operation. Big plus for the Navy was the size and power of the IR emitters they used but the image tubes determined distance more than the power of the light.

The optics of the Navy IR viewers were designed for distance. But they were looking for a direct IR light as opposed to IR light reflected off of something. If you used any of the Sniperscopes for viewing direct IR light instead of reflected IR light they can see for several miles. Just as with seeing headlights coming at you as opposed to headlights directed away from you to see what is in front of you.

The German IR equipment had similar limitations to ours. Especially their Sniperscope model which saw very limited use as it was still in R&D when the war ended. More common were the IR viewers and lights we see on their tracked vehicles. The ones mounted in front of the driver were a fixed position in line with where they were going. Ditto the IR light. The IR viewers on the machine guns weren't for targeting aircraft. Their viewers had a greater distance than our 1P25 tubes, more in line with our 6032 tube distance. The reason they were mounted on the MG's had to do with Russian infantry swarm tactics. The little I've read on the German IR equipment is it was primarily used on the Eastern front with some present on the Western front towards the end of the war and a training unit actively training in the west. It was the team captured by the Brits. They're hesitancy to deploy it on the Western front was the same as ours for deploying it there. Both sides knew their enemy had the ability to view infrared. Just not exactly who had that ability and where.

Could have gotten real interesting on the Western front. We had an IR viewer in some of the planes dropping our paratroopers. Looking for an IR homing beacon on the ground as the drop zone. The beacon was smaller than the German IR lights on their armor. Imagine what could have happened if the Army Air Force figured out those IR beams were German armor....


Edited by sleeplessnashadow - Jun 18 2019 at 10:10am
Back to Top
BER911 View Drop Down

Joined: Aug 04 2018
Location: Central VA
Status: Offline
Points: 314
Post Options Post Options   Thanks (1) Thanks(1)   Quote BER911 Quote  Post ReplyReply Direct Link To This Post Posted: Jun 18 2019 at 9:50am
Wow!  That is a very impressive and informative article.  That took a "little" research. Clap

Thanks Jim for your tireless commitment to our hobby and making this the "go to" website for accurate M1 Carbine information.

Semper Fi, Bruce
Back to Top
New2brass View Drop Down
Moderator Group
Moderator Group
Dan Pinto, Photo Editor

Joined: Nov 29 2015
Location: CT
Status: Offline
Points: 4594
Post Options Post Options   Thanks (0) Thanks(0)   Quote New2brass Quote  Post ReplyReply Direct Link To This Post Posted: Jun 18 2019 at 10:54am
Originally posted by jackp1028 jackp1028 wrote:

Dan & Jim, Great article! A couple of questions:

1) Dan, is your Sniperscope operational?

2) If so, is it possible to post an image of what the user sees through the scope to understand the capability of the technology at the time? Compare to contemporary night vision scopes.

3) Is it possible to show the relative difference in image quality between the Bell and Howell (M2) and Hillyer (M3) Sniperscopes to understand the level of improvement achieved?

4) The caution on the battery pack refers to recharging and vehicle connections. Was the Sniperscope ever intended to also be vehicle mounted, possibly for nighttime surveillance use rather than sniping?

Again, great article. I appreciate the effort you guys put into this.

1)Operational vs Working: Being that this is a limited production prototype some of the parts are "unobtainium".  The image tube is functioning which was my big concern. The image tube from the later scopes will not fit. The power supply passes all of the resistance and conductivity tests. 
Being that the scope operates at a high voltage I have concerns about the cable being taped up. 
I am debating restoring the cable or making a replacement.

There were a number of issues with the operation as mentioned. I plan on documenting and checking everything. 
I would say the unit is "Working" but not yet "Operational".

2,3) As Jim pointed out we will work on a M2 vs M3 comparison. 

4) the battery was rechargeable via a vehicle "generator". This would be today's equivalent of an alternator. Notice the socket on the side of the battery. There was a cable that plugged into the socket and had clips which could be attached to the vehicle battery or generator.

There is a charging rack to charge several batteries at once. This was designed to be run off a small portable generator or could be run off a vehicle generator.

Notice the two types of batteries.

Back to Top
jackp1028 View Drop Down
Hard Corps
Hard Corps

Joined: Jan 01 2016
Location: Cloudcroft, NM
Status: Offline
Points: 1262
Post Options Post Options   Thanks (0) Thanks(0)   Quote jackp1028 Quote  Post ReplyReply Direct Link To This Post Posted: Jun 18 2019 at 12:11pm
Jim, you mentioned the German use of IR beams on their armor and the possibilities of using these IR signatures for targeting purposes. I wonder if the Germans were aware of this possibility? Did the U.S. ever actually pursue this as an offensive deterrent? I guess the modern equivalent of this technology might be laser guided munitions where troops on the ground might "paint" a target with a particular laser signature that the munitions can "see". The similarities of these technologies is pretty incredible.    
Back to Top
sleeplessnashadow View Drop Down
Admin Group
Admin Group

Joined: Nov 09 2015
Location: SoCal
Status: Offline
Points: 1151
Post Options Post Options   Thanks (0) Thanks(0)   Quote sleeplessnashadow Quote  Post ReplyReply Direct Link To This Post Posted: Jun 19 2019 at 3:56pm

Our primary focus is and has been the IR scopes used with the U.S. .30 cal. Carbines. But they were only part of a much larger and more involved R&D effort by American scientists, their universities, and/or their companies. I avoid getting bogged down in researching the ops other than those in the U.S. but pick up bits and pieces and save things over time. At some point I'll look a bit closer at the German devices to see if they contributed to our post war IR research.

During the 1930's scientists from various countries were working with one another in the development of infrared emissions and infrared viewing. Many of the researchers knew of each other and the efforts being made if they had not actually exchanged information or cooperated with one another.

When Germany invaded Poland the cooperation stopped and switched to military applications for their particular country vs. the civilian applications they worked on prior.

The American, Austrian, British, and German researchers knew how far the various teams had progressed when they were tasked with doing IR research for their respective military organizations. The lead IR researcher in Austria was Jewish. He fled Austria and joined an American research team at the University of Rochester optics research center. His Rochester team came up with the phosphors that were needed for infrared viewers. His prior Austrian team did the same for Germany/Austria. All knew the Japanese weren't even on the playing field when the war started.

After the war started the agency at the heart of American R&D efforts of all kinds, IR included, was the National Defense Research Committee (NDRC). They were a civilian agency organized into various divisions to research various things (like the Atom Bomb) using America's scientists and researchers. They were separate from but available to the Army and Navy research labs. Almost all initial IR research was handled by Division 16 of the NDRC. When their research reached the point of the military issuing production contracts for a particular IR device the various military services took over the projects. The NDRC contracts were R&D contracts only.

In a nutshell, the NDRC IR research included everything anyone could even wonder about as a use for IR during WWII. Including the use of the Far Infrared region of the light spectrum for heat detection and heat signatures. With constant pressure to get them done and in the hands of troops that often sabotaged the R&D and handed the troops something that was near useless.

The beacon used for aircraft to identify drop zones accompanied an IR viewer mounted in the cockpit of aircraft. These were initially developed for use by the OSS as the radio beacons that were recent inventions didn't work in real life like they had in R&D. They had been made in limited numbers by July 1945. Preparing for the invasion of Japan a full scale production contract was in the works when the war ended. A few years later the CIA wanted improved versions and the research produced several subsequent versions.

The documents I've seen on the German devices and their use have indicated the Germans were just as concerned as we were about their IR lights being detected by enemy forces. Without the ability of knowing they had been detected. There are plenty of photos on the internet of a bunch of German half tracks and light armor equipped with IR viewers and lights sitting parked together. Some include the story that the German command had ordered them held to the rear during the Ardennes offensive. Where they sat until the war ended. Except for the training unit that arrived in the west at some point.

I've also found documents indicating the British ordered the IR viewers they developed held in the UK and not to be sent to their troops.

The ability of IR viewers to spot enemy IR lights is indicated in the NDRC documents as well as the army documents for R&D, testing, contract justification, etc. With all the concerns that limited the use of the IR equipment in Western Europe I'm surprised there has been nothing to indicate the viewers were actually used for that purpose. This may have had something to do with not knowing how many were in use, to what extent, and in what form. Or knowing they weren't being used enough to warrant the effort.

The situation in the Pacific was very different. The major concern there was the Japanese capturing one of the devices and realizing the extent to which they were being used by the U.S. Navy. Then re-engineering devices for use against us. Normal interruptions and other events have slowed my progress on an article I'm working on regarding the use of the sniperscopes and snooperscopes in the Pacific with a primary focus on Okinawa. I hope to have it completed and posted on this forum in the next month. Which I also said last month. Then the Hillyer M3 Sniperscope turned up. I'd been waiting for better photos of the pics in the Infantry Board Report for several months. They arrived just after the scope turned up. I had most of the info on the Hillyer scope already. Was just waiting on the better pics before doing an article.

The technology was still wearing diapers when the war ended but had taken a major leap compared to before the war. Many of the research projects had not achieved their goals when the war ended or a few years later when the NDRC was absorbed by other Federal agencies. IR devices for aircraft, armor, night driving, voice communication, heat signatures, and many other research projects had not progressed far enough to field some of these devices in other than R&D tests.

The IR work by the Germans and Austrians was studied by American researchers after the war. Often with the help of the German and Austrian scientists. Some of whom relocated to the USA after the war and became part of the research here.

In 1946 the NDRC published a series of books with an overview of most of the research they had done that wasn't still secret. Division 16 of the NDRC authored several books: one titled Image Forming Infrared. Another titled Non-Image Forming Infrared. These two books reveal the R&D and infancy of American infrared devices and technology of all types. Including those that never worked out. Their mention of the sniperscopes and snooperscopes was limited to just a mention with no details as the scopes were secret until 1946 then still classified.

The entire NDRC book series is available online and can be view at Library of Congress NDRC Series

All the infrared docs and research are more than a bit overwhelming trying to keep it all organized and pull what is needed for various things, articles included. There are a number of documents we are still trying to locate before building the web pages on the IR scopes. As well as photos and info from owners. Among other things it helps confirm what we see in the documents. Sometimes the documents and manuals indicate or omit things that were changed without the time to update publications.

Back to Top
Louis Losi View Drop Down
On Point
On Point

Joined: Jan 04 2016
Location: New York State
Status: Offline
Points: 367
Post Options Post Options   Thanks (2) Thanks(2)   Quote Louis Losi Quote  Post ReplyReply Direct Link To This Post Posted: Mar 11 2022 at 7:12pm
This article is from the June 1946 American Rifleman.

Back to Top
 Post Reply Post Reply

Forum Jump Forum Permissions View Drop Down

Forum Software by Web Wiz Forums® version 12.01
Copyright ©2001-2018 Web Wiz Ltd.

This page was generated in 0.109 seconds.