US Grenade/Fuze Data

[EODGUY]

Nothing earth shaking here, but I have been going through my files and put together some information that I thought might be of interest to some.
The T37E4 was adopted as the M31 HEAT rifle grenade. It was classified substitute standard in July 1953, and limited standard in June 1957, after the Army said they no longer needed an anti-armor rifle grenade.
The T38E1 fragmentation grenade was standardized in July 1953, as the M26. During development they also made the T38E2, T38E3, T38E4, T39E5 and T38E6 designs each with a minor variation in the body for testing fragmentation results.
The T39 was adopted as the M30 Practice grenade.
The T41E1 was adopted as the M28 HEAT rifle grenade. It was in use from 1952 to 1955.
The T42 was adopted as the M29 Practice rifle grenade.
The T45 was adopted as the M27 Illuminating rifle grenade.
The T54 grenade was adopted as the M33 grenade. During development the grenade was referred to as the "Birdie".
The straight lever version of the T2 fuze was adopted as the M206 for use on the Mk 3A1 offensive grenade and the M15 WP grenade.
The T2E1 cured handle version was adopted as the M204 for use on the TNT filled Mk II fragmentation grenade.
The T16 fuze was adopted as the M205 for use on the M21 practice grenade.
The T1011E2 fuze was adopted as the M213 for use on the M33 and M7 grenades. Same as the M215 fuze except for the curved handle.
The T1011E3 fuze was adoped as the M215 for use on the M26 and T43 gernades. It was a modified M2o4A2 with a shorter detonator. Development began in January 1949 and it was made standard A in May 1959, replacing the M204A2, which was then made standard B.
The T1012E1 fuze was adopted as the M217 impact/delay fuze for the M26A2 and T43 grenades. The program opened in June 1951.
The T1014E1 fuze was adopted as the M211 and was made substitute standard in July 1953 at the same time the T37E4 grenade was made substitute standard as the M31. The M211 was classed as limited standard in June 1957. This was the first US piezoelectric rifle HEAT grenade fuze.

All development on HEAT rifle grenades and their fuzes was terminated when the Army approved the study for the 66mm LAW. The only fuze that continued was the T1022 because it had interest in the Marine Corps.

Bob

 

[raymeketa]

Bob

Maybe it's not earth shaking to you, but good stuff for the rest of us. A copy goes in my files, with your permission of course.

Ray

 

[dano1917]

Thank you Bob, Very nice. I do feel the earth shaking as I have this page bookmarked for quick reference. Like having a quickie reference at your fingertips. Very useful....Dano

 

[GTR003121]

Great info Bob, thanks for posting.

Do you have more on the M33 Frag and more on the M213 such as dates?

 

[V40]

Thanks Bob for a probably time consuming information is Bob, thanks for your time and effort.


Probably should become as a "Sticky" ?

 

[EODGUY]

Unfortunately I do not have detailed information on the M33 grenade. As for the M213 fuze, the Army set out a requirement for a noiseless, smokeless, sparkless fuze with a uniform burning time in the mid 1940's and it was repeated in the Equipment Developmennt Guides of 1950 and 1954. In January 1949, the Army initiated development of the T38 fragmentation grenade and a fuze with a 4.5 second delay (plus or minus 0.3 second) to meet the above requirements. The fuze was designated the T1011. In August 1955 the T1011E1 was undergoing final engineering tests. The most signifcant difference between it and the M204A2 in use at the time was a shorter, more powerful detonator, which required a modification of the M26 grenade fuze well for use of the fuze. Because of problems with the booster in the M204A1 causing unreliable performance it was decided not to use a booster in the T1011 fuze, therefore a larger detonator containing 26 grains of RDX (as opposed to 12.5 grains in the M204A1) was used. The detonator was larger in diameter and crimped directly to the delay housing and not the extended nipple of the earlier fuzes. Early M204A1 fuzes had two piece bodies and so did the T1011 fuze. Before completion of the development of the T1011 a procedure was developed to make a one piece zinc die-cast body for the M204A1, which then became the M204A2. The same technique was used for the T1011 which resulted in the T1011E1 with a one piece body. User tests by the Infantry Board and Arctic Test Branch resulted in both agencies recommending adopting the T1011E1 as standard in 1958. At that time the detonator case length and diameter were enlarged to function in the modified M26A1 grenade and the thread size was changed. It was then designated the T1011E3 and was classified standard A as the M215 in May 1959, and development terminated. This fuze replaced the M204A2 which was made standard B at this time. At the same time the T1011E3 was standardized, the modified M26A1's were classified standard A as the M26A2.
The details on the M215 are:

Type: Pyrotechnic delay
Body material: Zinc alloy
Lever: Steel
Striker: Steel
Detonator case: Aluminum
Weight: 2.6 oz
Length without lever: 3.03 in.
Visible length: 0.85 in.
Thread size: 5/8-11UNC-2A
Primer: M42
Delay charge: 20 grains Type II delay composition
Delay time: 4-5 sec.
Detonator: 1.5 grains lead styphnate igniting charge; 7.5 grains lead azide upper charge; and 25 grains RDX lower charge.
Safety ring pull force: 10-30 lb.

Hope this didn't bore anyone.

Bob

 

[EODGUY]

Gads, I got so carried away I forgot to answer the basic question. Unfortuantely, I do not have specific details on development of the M213, but given that it was developed as the T1011E2 and the same as the M215 except for the handle/lever, my guess is that the adoption dates were pretty close to the same, which was the case with the M204 and M206 with similar handle configurations of the T2 series fuze. Sorry for not including that in the first posting. Bob

 

[GTR003121]

Thank you Bob, still a wealth of great information and very helpful! I'm sure none of us are bored and I for one am very grateful! Thanks again!

 

[ordnance]

Bob,

Thanks a lot. Those are a great couple of posts. Lots of information to digest there.

One assumption of mine was certainly put to rest. I always wondered why the change was made from the 9/16" fuze threads to 5/8" with the larger detonator well in the M26 series grenades. I always believed the change was necessary to accomodate the complex engineering within the M217 impact fuze.

Now it appears the change was just to allow a larger detonator to insure positive detonations. I assume the tetryl booster rings around the fuze well were no longer needed in later production grenades with the 25 grain RDX detonator. Interesting stuff!