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  1. #1
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    Default South African 7.62 NATO question...

    What is the difference between the South African R1M1 and M1A2 7.62x51 ammo?

  2. #2
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    No idea?

  3. #3
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    The last statement regarding R1M1 ammunition being 5,56 and R1M2 being 7.62 x51 is not accurate! RSA Ball 7.62 x 51mm ammuntion up to around 1981 is seen with headstamps including Mk.1, A1 or R1.M1. Examples of 7.62 x51 cartridges with R1M2 in the headstamp exist from 1981 to 1982. In 1983 RSA started using a two position headstamp - year at 12 o'clock, type at 6 o'clock. This change in headstamp layout appears to correspond with the change in designation from 7.62 R1M2 to M1A1 through M1A3.

    The information I have regarding the RSA R1M1 designation system is that the R1 means that the cartridge is the first model of that particular caliber. Any change in design or manufacture that would alter the operational efficiency would lead to a change in R number ie R2, R3 etc. The M1 refers to the mark number. Any change to the cartridge that would not alter the opporation efficiency fo the cartridge would lead to a new M number ie M2, M3 etc. This convention is seen on other calibers besides 7.62 x 51.

    In saying all this, I'm not sure of the difference between 7.62x51 R1M1, R1M2 and the M1 series. If I can find duplicates in my NATO collection, I'll pull the bullets and see if there is any obvious difference in bullet weight, powder charge or powder weight.

    Bracken S

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    Red Baron, you and Janes (if that is where you got your info) are both incorrect, Braken is spot-on. The R/M numbers are model designators within a particular weapon, caliber, or other piece of equipment. Less than one hour ago I was shooting South African 7.62 marked R1M1. I do not believe the South Africans relabeled ammo boxes to confuse the contributors to the Janes series. You will also find R1M1, R1M2, etc. within 5.56. The Janes ammo book is well-known for significant errors, usually repeating erroneous info from other sources without doing their own research. Do not believe everything you read on the internet or from a single source. In this case, you got bad info.
    Last edited by jonny c.; 01-11-2009 at 01:31 PM. Reason: spelling
    Always looking for interesting 7.62x25 Tokarev and 7.63 Mauser cartridges!!!
    Member: International Ammunition Assoc. (IAA), European Cartridge Research Assoc. (ECRA). Ask me about membership!

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    Neither I nor Jane's are incorrect. You are making the assumption that the R and M numbers designate caliber based on just two examples. What Jane's actually shows is a single example of a 7.62 x 51 cartridge - first model (hence R1) second mark (hence M2) and a 5.56 cartridge - first model (R1) first mark (M1). Shown below is a photo of a box of 7.62 x 51 R1M1 ball ammuntion clearly showing that the R1M1 designation is not unique to 5.56 ammunition (I have seen multiple examples of 7.62 x 51 boxes with an R1M1 designation that show that your statement is incorrect) RSA 9mm ball is found with an R1M2 headstamp and is boxes clearly maked 9x19mm Ball R1.M2. (see photo). While I don't have photo's, RSA 50 BMG cartridges have headstamps such as A72 12.7 R1M1 and A80 R1M3. RSA also made 7.62 x 39 ammuntion that included R1M1 in the headstamp. Looking at Dave Hughes' authorative book on the M16 rifle and its cartridge and and his extensive listing of known cartridges, RSA 5.56 cartridges can be found with headstamps with both R1M1 and R1M2 in them. He also gives a similar explanation as to meaning of the R1M1 etc as I gave in my original posting.
    Based on the information I have at hand (from multiple independent sources), I stand by my oringinal posting and find nothing to suggest that what I said is inconsistent with the limited information shown in the Jane's year Book.
    Bracken S

  6. #6
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    Cool

    Quote Originally Posted by Red Baron 208 View Post
    bracken, you are wrong, need to check your facts. These cartridges are illustrated in JANE'S INFANTRY WEAPONS 1984-85 just as I stated.( A 81 7.62 R1M2 ) and ( B82 5.56 R1M1 )! Are you saying that JANE'S is wrong and you know more, don't think so.

    Sorry, but I have several battle packs of 7.62, and they ALL are stamped R1M1.
    You can't trust EVERYTHING you read.

  7. #7
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    It is just like in US service...You have an "M1" rifle, "M1" canten cup, "M1" entrenching tool and so on ad infinitum..... Mods to the original item get you M1A1 and so on...

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    Vim, tough to tell, but did you get the answer to your question yet? I'm sure Braken will get back to us with some specific details. If anyone has the answer on 7.62 Nato, he does...I've seen his collection of Nato rounds, boxes, and trivial stuff.
    Always looking for interesting 7.62x25 Tokarev and 7.63 Mauser cartridges!!!
    Member: International Ammunition Assoc. (IAA), European Cartridge Research Assoc. (ECRA). Ask me about membership!

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    Quote Originally Posted by jonny c. View Post
    Vim, tough to tell, but did you get the answer to your question yet? I'm sure Braken will get back to us with some specific details. If anyone has the answer on 7.62 Nato, he does...I've seen his collection of Nato rounds, boxes, and trivial stuff.
    I might pull some apart myself just for the giggles.

  10. #10
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    I remember reading a lot of posts about the different lots of South African 7.62x51 while large quantities were being imported a few years back. Supposedly one of the differences was in the type of sealant used around the bullet. Some people claimed that certain lots of this ammo used a tar-like sealant that caused problems in Cetmes. There is no doubt a lot of information about this archived in the FAL and Cetme forums.

  11. #11
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    Just pulled bullets from an RSA 7.62 R1M1 (headstamp A81 7.62 R1M1) and a 7.62 M1A2 (headstamp 88 12). The only obvious difference is in the powder. The R1M1 uses stick while the M1A2 uses fine ball.

    Bracken S

  12. #12
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    Quote Originally Posted by bracken s View Post
    Just pulled bullets from an RSA 7.62 R1M1 (headstamp A81 7.62 R1M1) and a 7.62 M1A2 (headstamp 88 12). The only obvious difference is in the powder. The R1M1 uses stick while the M1A2 uses fine ball.

    Bracken S
    Thank you. Did you check the sealant? The tar like stuff in late 70's R1M1 has not caused any problems in my PTR-91 yet.

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    It gummed up my PTR pretty quick. Anybody chronographed this ammo against Port or Hirt? I suspect that the SA is slightly underpowered.

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    Quote Originally Posted by Super B View Post
    It gummed up my PTR pretty quick. Anybody chronographed this ammo against Port or Hirt? I suspect that the SA is slightly underpowered.
    Had the opposite experience.... ran 500+ rounds through mine without any cleaning and didn't have any problems. Even pulled a bullet to see if it was a the tarred stuff and sure enough it is.

  15. #15
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    Quote Originally Posted by bracken s View Post
    Just pulled bullets from an RSA 7.62 R1M1 (headstamp A81 7.62 R1M1) and a 7.62 M1A2 (headstamp 88 12). The only obvious difference is in the powder. The R1M1 uses stick while the M1A2 uses fine ball.

    Bracken S
    Ammo makers often switch powder types in ammo as cost, availablity etc come into play. Loads will be standardized using the new powder type without any need to change model numbers. I have had batches of Port. 8mm Mauser M937 ammo with Ball, stick, and Flake powders.

    I have seen several guesses about the SA model numbers...but no documented story that holds up. They may have just changed their nomenclature system at some point.

  16. #16
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    Quote Originally Posted by Super B View Post
    It gummed up my PTR pretty quick. Anybody chronographed this ammo against Port or Hirt? I suspect that the SA is slightly underpowered.



    I don't have a chrono, but I agree with the under-powered angle.
    In my M-1A it ejected less than half the distance of Hirt, etc.
    And the recoil was noticeably less.
    So I decided to save it for my No. 2 Ishapore.

  17. #17
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    All this chest-thumping about who has read the most and has the most reference books passes me by, I have to say. I can't afford to collect boxes and boxes of ammo like you guys can. I'm limited by law to 700 rounds of .308 and I buys it and shoots it.

    In my 26inch barrel Krico it averages 2555fps and in my K31-actioned Hammerli it averages 2611fps. [Every now and then we have to chrono loads for the Home Offfice who clear our range and authorise it for use.]

    I squeezes the trigger and it goes bang and is pretty darn accurate out to 900 yards, which is as far as I've shot it.

    Now there is no more in UK I miss it like heck and no, the tar never caused ME any problems in cleaning up afterwards, either.

    Oh yes, all the boxes were marked up like the one shown in the post as well.

    tac, a shooter, not a box interpreter.

  18. #18
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    "tac, a shooter, not a box interpreter."

    That's fine, but that's what was needed to answer the original poster's question.
    Always looking for interesting 7.62x25 Tokarev and 7.63 Mauser cartridges!!!
    Member: International Ammunition Assoc. (IAA), European Cartridge Research Assoc. (ECRA). Ask me about membership!

  19. #19
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    Shot from a 21" barrel - FAL - velocities taken 10' from muzzle

    SA 78 R1M1 ...... 2689
    Radway Green 84...... 2775
    Aussie 88................ 2818
    Paki 80.................... 2696
    Hirt 79................... 2764
    Port 76..................... 2654
    Cavim 88..................... 2707

    http://www.falfiles.com/forums/showt...mmo+Velocities
    Last edited by Muggzy; 01-20-2009 at 12:33 PM. Reason: add info

  20. #20
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    Does anyone know the projectile weight used in the R1M1?

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    According to label on my crate it is 146 grains
    Life is short. I`m trying to get the most out of what`s left.

  22. #22
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    Quote Originally Posted by alf1960 View Post
    According to label on my crate it is 146 grains
    Excellent! Thanks a lot for your help.

    Cheers
    Jeff

  23. #23
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    I had some R1M1 that would short cycle in two M14 clones and a 308 Garand. It chrono'd faster than my target reloads. If memory serves, velocities in the high 2600fps range indicated it wasn't "week" in that department. I assumed the port pressure produced by the powder curve wasn't compatible with the M14 and traded it to a FAL friend. He liked it.
    How many psi in a CUP?

  24. #24
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    Quote Originally Posted by Fredericianer View Post
    Does anyone know the projectile weight used in the R1M1?


    I believe it is advertised as 147gr. But when i pulled bullets and weighed them I got 142.something grs.

    If you will click on the blue liner in my post it has the break down of R1M1 components


    142.6 gr i

  25. #25
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    Quote Originally Posted by Stoner208 View Post
    South Africa was never a NATO member, consequently never made NATO ammo although they did use both UK and NATO Colour codes. "R1M1" is 5.56 x 45 , "R1M2" is 7.62 x 51. Code for Pretoria Metal Pressings (PTY) Ltd, Pretoria
    No, Need to check again.

  26. #26
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    Thanks, Mugzy!!!
    There's nothing more dangerous than a colossal, bankrupt, and well-armed government--- Porter Stansberry

  27. #27
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    Default Late to the party but here are some pictures that may lay this to rest.

    Headstamp on this appears to my old eyes to be B81 which I am assuming to be the date of manufacture? I believe it was Alan on one of the forums who posted some good information about this ammunition. According to his listing SA ammo did not use a boxer primer until 1990. I was disappointed to hear that as I was saving brass to send to a friend. I will just hold onto the brass until some Berdan primers become available again. Bill Hurley aka Sarge.EDIT: I did crop these but they posted as in the original. I have been having trouble with my picture uploading. Sorry about the unnecessary information. Bill.
    Attached Thumbnails Attached Thumbnails DSCF0035.jpg   DSCF0036.jpg  

  28. #28
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    The South African "RxMx" system of nomenclature is exactly the same as the British Commonwealth "LxAx" system, where "x" represents digits from 1 to wherever.

    IN the Ammo field, each calibre had an "L" designator, and these went upwards as variations occured in case design, bullet design, powder changes, etc. Completely changed cartridges were given a new , different "L" designator ( such as L5 for (7,62) tracer, etc, and the "A" designator handled all the Minor changes.

    THis was also used in Weapons designs, the "A" being the modifications in time and series ( Just like the US "A" designation).

    South Africa originally used the British "L" system, then with increasing Independance and expulsion from the Commonwealth for its Apartheid program, adopted the very similar "R x M x" Notation ( R being "Republic" ( of South Africa) and "M" being Modification...Note that the initials are the same in English and Afrikaans, the Dutch origin language of many in South Africa, and an official Language up till the overthrow of the White Nationalist Gov't.

    I concur with the statement that Jane's is often seriously wrong in a lot of matters regarding details of Ammo etc...it is just too big a publication system....when it was only about Naval vessels, it was fine...now they try to cover every man and his dog ( sorry, Gun) and the results are not encouraging.

    BTW, even small differances such as the type of neck sealant etc, can affect both the "LxAx" system, as it could affect the "RxMx" system. Different suppliers of British ammo also got different "A" numbers for their ammo ( eg, Hirtenberger 9mm, Kynoch contracts pre 1970, etc.

    Regards,
    Doc AV
    AV Ballistics

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