Bill Ricca's U.S. Caliber .30 Carbine Flash Hiders

William J. Ricca Surplus Sales

Government Surplus 1971-2018

All rights reserved, Bill Ricca ©
Reprinted here by The Carbine Collectors Club
with Bill's written permission

US Caliber .30 Carbine
Flash Hiders

The purpose of this study is to dispel some of the myths about Carbine Flash Hiders and to help interested individuals understand the history of their development and production. I have included pictures of all the US GI versions and some foreign ones too, but unfortunately the markings are very small and not heavily struck. Each photo has the actual marking duplicated in the caption. All research work comes from Ordnance Committee Memoranda, Ordnance Department historical documents, Technical Manuals, and by cataloging several hundred Flash Hiders over the last 20 years.

The T23 Is Born

The first requirement for a Flash Hider (FH) was in the fall of 1944. Aberdeen Proving Grounds (APG) was given the task of designing one based on the M1 Rifle’s existing cone flash hider. APG made six pilot models by removing the tubes from M8 Grenade Launchers (GL) and building upon their mounting brackets by adding a steel funnel. The result of the alterations were designated Hider, Flash, T23. The angle of the funnel was changed from the Garand’s due to line of sight interference caused by the Carbine’s different sights and sight radii. Like the Grenade Launcher the wing nut locking the T23 was in the top position mounted above the barrel.

Ordnance tested the ability of the T23 to prevent potential enemies from observing the shooter's flash. Observation tests were done at 25, 50, and 100 yards at 20 degrees from the line of fire. The tests were conducted at the Ordnance Research Center (ORC) using two of the six pilot models.

The tests were conducted with the following additional criteria:

    1. Ability to maintain accuracy with FH attached.
    2. Retention capability of the wing nut during recoil in semi and automatic fire.
    3. Further modifications to add the reduction of muzzle climb in automatic fire.

The T23 reduced observable flash by 95%. Test results showed no significant change in accuracy but serious problems with the wing nut. Operators had to keep their constant attention on the device, often having to retighten it after just 75 rounds. Field reports had shown minor problems with the M8 Grenade Launcher’s wing nut vibrating loose. This problem, although minor for the GL, represented a serious problem for the T23 as plans were being discussed to supply one for each T4 Carbine (M2).

Results also showed the design worked satisfactorily as a FH but altering its design to reduce muzzle climb was not practical. Each physical change that redirected gasses to reduce muzzle climb decreased the ability to hide the flash. The idea of combining the two functions was dropped. Later testing of the T12 and T13 Recoil Checks would lead to the post war adoption of the Recoil Check, M1. I will have a future article on the development of the M1 Recoil Check.

In early 1945 the Office, Chief of Engineers (OCE) requested the T23 be classified as limited procurement and requested one for evaluation. APG provided the Engineer Board with one of the pilot model T23's. The OCE was immediately impressed with its flash hiding capabilities and had 1700 manufactured for use with the M2 Sniperscope (Infrared). The M1 and M2 Sniperscopes along with the T3 Carbine are areas of research in themselves. The purpose of this writing is limited to Flash Hiders so I mention the above strictly for reference.

First Production T23 made for OCE.

In the mid 1970's a company called Texas Armament made a very good reproduction of the above Flash Hider. Its markings were bold, correctly located, but differed in font size and overall construction. Texas Armament went so far as to even place the wing nut in the top position as was the case with all T23 FH's. It was so close that I would not recommend paying big money for one, unless you know how to distinguish both. If you know what to look for you can tell immediately. I will not go into the details otherwise internet hump artists will soon start a production line. I haven't been able to determine who made the T23 shown above. What is known is that it is was contracted by the Office, Chief of Engineers. All characteristics differ greatly from those known to be produced at Springfield Armory.

During this period of time two other designs were tested. The T23E1 and T23E2 were attached to the carbine with a bayonet type locking device. Both had problems with fitting as ordnance had recently allowed production of a stamped front sight to speed up production. This stamped sight had side walls that were made of steel that was thicker than earlier milled versions of the sight. That thicker steel interfered with the locking ability of the two designs. Since carbines were now in existence with the stamped front sights, the decision was made to drop both designs and no further consideration was given to either.

Springfield Armory and the T23

Springfield Armory had the responsibility to produce a small quantity of T23 Flash Hiders with nylon washer inserted in the wing nut, for further testing. The nylon washer was an attempt to solve the problem with the wing nut vibrating loose. Characteristics of Springfield Armory's T23 are different than any other T23. Throughout the years a few of these SA "Cigar Band" marked T23's have surfaced with two different markings. The existence of two markings can be something as significant as two different production runs, or something as simple as different tooling being used during production. A few of these hiders survived and got into use toward the end of the war on the M2 Sniperscope. The SA T23 has the wing nut mounted in the top position, a characteristic of all T23's except for one of the six pilot models that was eventually modified at the end of testing.

In April of 1945 some Springfield Armory T23's with the new wing nut and one of the original pilot models now designated T23 Modified with the new wing nut mounted below the barrel were delivered to the Infantry Board for testing. The wing nut had been moved below the barrel to prevent line of sight interference. This was the last change for the T23.

In the same month, April 1945, Headquarters, Army Ground Forces, based upon the tests at the Infantry Board recommended that the T23 Modified with the wing nut having a nylon washer inserted and having the wing nut mounted below the barrel (bottom position) be adopted for use with the M2 Carbine. Testing showed the nylon washer had provided enough resistance to prevent loosening. I quote from the Record of Army Ordnance Research and Development: “the basis of issue of this flash hider be one per Carbine, Caliber .30, T3 which is a part of the Sniperscope, M2, and one each to combat and combat support troops armed with the M2 Carbine”.

Cigar Band Type Markings of Springfield Armory's T23:
Hider, Flash- T23 SA (Shown) Hider, Flash T-23 SA (not shown).

Photo of T23 Modified from Record of Army Ordnance Research and Development.
Field use dictated the Wing Nut be moved to bottom position to prevent line of
sight interference. Visible is hand stamped marking on this prototype, one
of the six original APG pilot models, the only pilot model modified as such.

On 9 August of 1945 the T23 Modified with nylon washer inserted into the wing nut mounted below the barrel was recommended for standardization for the M2 Carbine as the Hider, Flash, M3. On 27 September 1945 the T23 Modified was approved for standardization for the M2 Carbine as the Hider, Flash, M3.

Post war things would change. The M1 Recoil Check eventually would be adopted and produced for the M2 Carbine. The M3 Flash Hider would be issued strictly with Infrared Sights.

The War In Korea and Production of the M3 Flash Hider

Soon after the Korean War started the Corps of Engineers, US Army developed and contracted for a new Infrared Sniperscope. The new item was designated Sniperscope, Infrared, Set No. 1, 20,000 Volts. With new technology available a new unit could be built with results of a better, more efficient sniper system.

In August 1951 two publications were rushed into print. TM 5-9341 covered the M1 and M2 Sniperscopes and superceded the same printing of September of 1944. TM 5- 9342 was a new publication dealing with repair and maintenance for the new 20,000 Volt, Set No. 1. Both publications were titled Operation and Maintenance Instructions for....... the appropriate Infrared Scope(s). The illustrations in these two publications can give us an idea as to the timing of the Flash Hiders' production and availabilities. An examination of the publications shows that as of August 1951, the date both were published, the T23 was still in use, and most likely the M3 had not yet been fielded. The Engineer Branch of the US Army had responsibility for production of Infrared Sniperscopes, their tools, accessories, and publications. TM 5-9342 is quite specific in the types of tools and accessories for the 20,000 volt unit, but nowhere in the publication does it mention the M3 Flash Hider.

I have an SA marked M3 in an SA wrapper dated 26 March 1956, but that may not necessarily signify the production date. SA may have repacked the FH for storage shortly after the Korean War had ended, I don't know. I have seen no documentation as to when the two US GI Flash Hiders with M3 characteristics were produced. My guess is 1952-1953 for Underwood Corp, and Springfield Armory probably later. Whatever the case Springfield Armory M3's have always been available in lesser quantities than the Underwood Corp. M3's.

T23 in use on the M2 Sniper Scope, from TM 5-9341, Aug 51
Note Flash Hider's Wing Nut in Top Position.

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