Cal. 50, yellow over red


Just got this. Odd pointy end. Appears there may be something lurking within the projectile. I don’t know.


This is my first shot at a reply here on the forum, hope I do it right…
The rounds you have appears to be an XM156, Spotter-Tracer, the bullet has a primer in the open nose. Works the same as the BAT M48 Series of Spotter-Tracer rounds for the 106mm recoiless rifle.
Info on this round was gleened during a visit to Woodin Laboratory while obtaining info for our 50 Cal BMG Reference Book. You can view the Book in its entirety on line through the following link (it is free!!):
50 Cal BMG Book Link …


[quote=“RonFuchs”]This is my first shot at a reply here on the forum, hope I do it right…

Welcome! Looks like you did it right.

That is an AWESOME reference to .50 Cal headstamps manufactures and variations!!! Almost makes me want to start collecting them! ha!



I agree with Aaron, an excellent first post. While waiting for the download to complete, I thought I would add that I initially thought spotter, but the case was too long. At 75% downlod. I’ll be back with comments shortly.

OK. After a quick look-see at the book, just one question: Can you advise which page this particular round is identified?

Update #2. This looks interesting: … nance.html

For somebody who’s into lists.


The British Army used .50 BMG spotter/tracers in tanks in the 1950s and 60s (maybe later, I don’t know) as a form of rangefinder. They fired the .50 cal until the bullets were hitting the target, which gave them the range for firing the main gun.

They used two bullet types:

L11 series, for the Centurion tank (105mm gun), traced to 1000m, had tracer and flash compound, tip colours: yellow over red as shown in your pic.

L13 series, for the Chieftain tank, traced to 3000m (120mm gun, had much longer range), tip colour: purple.

France used the .50 BMG in tanks in the same way, there were maybe others also.


Sorry to correct you Tony, but that is not the case.

The L11A1 and L11A2 were identified as you say with the yellow over red tip code for spotter rounds. The purple tipped round (actually violet) was the marking for the experimental pre-production XL13E1 round. A violet tip or band is only used in British service for experimental ammunition. When the L13A1 entered service in the mid 1970s it had the same yellow over eed tip for spotter ammunition as the L11 series.

Picture 1 shows a several experimental L11 spotters with the L11A1 round. The L11A2 looks identical to the L11A1. The mustard tip round is an L11A1 filled inert for calibration work.
Picture 2 has the XL13E1 and serrvice L13A1.



The Book is “headstamp” driven, so go to the U.S. - TW section #152.2 and you will find it under T W 5 2


Tony E.
Great pics! Could you supply the headstamps for the rds pictured, I would like to make sure I have them in our Book. Many Thanks


Ron, thank you very much for being so generous to share your book!


[quote=“EOD”]Ron, thank you very much for being so generous to share your book![/quote]Yes indeed, though I have problems extracting certain files, those that have an index mark between the page number and the title of the document i.e. 101¤Title Page or 114¤Denmark. All the others work fine i.e. 111.3 CANADA Sec C (IVI 96 etc.
Maybe its my unpacker (Peazip) that has a problem with index marks or the newest Adobe reader (9.4.1)
What I can unpack is very fine work.

¤ marks where the index mark is. The reaction is “Operation stopped, invalid file name detected”

EDIT: Problem solved


If you liked the 50 BMG go to the below link for a 5.56 / 223 list.


Ron / Pete, thanks a lot again! What a great source of information!


I’m entirely agree. Many thanks for this great job.


M48 Spotter Tracer projectile loaded into a TW 52, reloaded, .50 BMG case, intended for shooting. Not original, not factory.

The M48 series projectile is rather spectactular for shooting.


I am greatly embarrassed… I thought the info I had was correct, but it is not and I am truly sorry for any confusion I may have caused! Not a good start for me on the Forum, a place that I read regularly with confidence… Apparently the T W 5 2, is nothing more than a remanufactured round from surplus components. I am very grateful to Frank Hackley for setting me straight, and I thank him sincerely! The following is info he just provided to me:

I am not sure what the T W 5 2 so called Spotter is, but it certainly not the XM156. Only two small experimental lots of the XM156 were loaded at FA during 1961-1962 and both were H/S F A 6 0 and these used brass primers and red sealant with the red/yellow bullet tips. The XM156 also used a primer flash - tube and the .50 MG case was modified to change the shoulder angle to properly chamber in the XM121 MG which was used as an interim spotting weapon for the Sheridan Armored Vehicle 152mm Gun-Launcher.

I will now go back into my “hole” and just listen…



Thanks much for sharing that great mass of information! Very nice.


Here is a loose Spotter/Tracer projectile. Shows just how much there is below the cannelure.

These are what I assume to be M48 pull-downs and are out there on the gun show circuit. I had seen the British full size .50 BMG Spotter/Tracers but have not seen the equivalent U.S. product. Don’t mean nothing for sure, but Keith may be on the money in that your example is a reload utilizing surplus projectiles. On the other hand, I wouldn’t know an XM156 if it walked up and kicked me in the shin! Perhaps someone has more info on the U.S. experimentals to add to the discussion.

This is a link to the Cartridge of the Month showing a beautiful section job by Paul Smith:

Added: Ron posted while I was typing… Thanks for the new information! Don’t worry about the missed ID. The important thing is that we put together what we know and come out knowing more!



[quote=“TonyE”]Sorry to correct you Tony, but that is not the case.
Thanks for the correction, Tony, I will amend my notes!


Firstly, thanks for all the input on this.

As it came in a lot of assorted, vintage Cal. 50s, my thoughts are that it is original. Not a basement reload. If it is a “reload”, it was done on a fresh, primed, mil case. The primer has the original staking, so not from a fired case. No striations to suggest resizing nor appearance of a cannelure re-crimp. There are case scratches that suggest its having been belted at some point. Maybe just for display.

Some of the pros are scratching their heads. I, as usual, have no clue.

This specimen will soon be in the collection of one of our esteemed officianados. A pending settlement has been put on hold until a definitve ID can be established. He’s either gonna get one hell of a deal, or something for a future trade “gimme”. My hope is it’s extremely rare and I’ll need to clear out some space in the OrdHut® to make room for the results of the trade. Nudge-nudge, wink-wink.


Ron- Great work on the Book.

Now, how will our bibliography people include this in the IAA Bibliography, since it is not a paper and ink book?

I will add a link to it on the IAA links page next time I update that.



I will now go back into my “hole” and just listen…[/quote]

Ron, due to you we still got the correct info and a very interesting thread and also two very interesting books (even for free). I can’t see anything incorrect there. If nobody will stand up and show something we all will remain uneducated since nobody will correct our mislead assumptions and noone is here to whom it did not happen in the past. Welcome here and keep going!