IMR 4831 - where to find ? - Reloading Methodology https://systemz.online/reloading-methodology/imr-4831-where-to-find/ AllGunStuff Discussion Board en-US Fri, 08 May 2026 10:23:01 +0000 wpForo 60 Re: IMR 4831 - where to find ? https://systemz.online/reloading-methodology/imr-4831-where-to-find/#post-7606 Sat, 07 Mar 2026 21:45:45 +0000
Norma MRP seems to be freely available.

Yes thanks I looked at that one - as well as IMR 7828SSC
Unfortunately :'(  .. here - no one has any  :(
From one of the US forums ..

Alliant Reloading
Reloder(R) 23 is awesome! It was our second product in the TS family and is proving quite versatile in the faster end of the magnum range. It is probably the most used propellant in our Federal Custom Shop, where we use it in 6.5-284 Norma, 6.5 PRC, 7mm Rem SAUM, 280AI, 7mm Rem Mag and 300 Win Mag. Like all of the TS products, temp stability is outstanding, and you almost have to work at not getting low single digit velocity sd's and great accuracy.
Our only issue with TS 23 and all of our products is getting, packing and shipping enough to catch up with demand. I believe that will happen soon though, as long as eastern Europe stabilizes.
Good luck with your newfound treasure Matt_3479.
Shoot well,
Paul

WWeelll
Eastern Europe has NOT stabilised
and
Now we have the Middle East .. unstable
and
Unlike in the US we cannot purchase 8lb kegs of powder ..
]]> Reloading Methodology Newton https://systemz.online/reloading-methodology/imr-4831-where-to-find/#post-7606 Re: IMR 4831 - where to find ? https://systemz.online/reloading-methodology/imr-4831-where-to-find/#post-7605 Sat, 07 Mar 2026 11:19:06 +0000 Reloading Methodology Tripodmvr https://systemz.online/reloading-methodology/imr-4831-where-to-find/#post-7605 Re: IMR 4831 - where to find ? as well as Alliant Reloder 23 https://systemz.online/reloading-methodology/imr-4831-where-to-find/#post-7603 Sat, 07 Mar 2026 09:51:51 +0000 Where to find that one ?
Appears everyone also out of stock of that choice

Because the rifle I have was - in a previous life re-chambered it has a very long "throat"
This changes all the dynamics as the bullets are seated much further out of the case giving more internal capacity

RL23 is one of the few powders ( in MY application ) where one can obtain nearly 100% fill ratio and still be within pressure limits .. without using too much powder
I do not think that there is any burning rate equivalent that will do this ?
]]> Reloading Methodology Newton https://systemz.online/reloading-methodology/imr-4831-where-to-find/#post-7603 Re: IMR 4831 - where to find ? https://systemz.online/reloading-methodology/imr-4831-where-to-find/#post-7597 Fri, 06 Mar 2026 23:49:56 +0000 Reloading Methodology Tripodmvr https://systemz.online/reloading-methodology/imr-4831-where-to-find/#post-7597 Re: IMR 4831 - where to find ? https://systemz.online/reloading-methodology/imr-4831-where-to-find/#post-7596 Fri, 06 Mar 2026 21:16:18 +0000
Even if I did not have your rifle data the info is relevant regarding performance.

Indeed
Nowhere did I say it was not relevant

Not your problem we are so constrained in terms of choice
It is however academic having so many powders listed which we are likely to never see

I do however think that a 165gr projectile for a 300WM is a bit  ... light

]]> Reloading Methodology Newton https://systemz.online/reloading-methodology/imr-4831-where-to-find/#post-7596 Re: IMR 4831 - where to find ? https://systemz.online/reloading-methodology/imr-4831-where-to-find/#post-7584 Thu, 05 Mar 2026 01:30:19 +0000 Reloading Methodology Tripodmvr https://systemz.online/reloading-methodology/imr-4831-where-to-find/#post-7584 Re: IMR 4831 - where to find ? https://systemz.online/reloading-methodology/imr-4831-where-to-find/#post-7583 Thu, 05 Mar 2026 01:26:27 +0000 I do have QL as well as GRT
SO alternatives not so unknown to me
Out of all those you list local gunshops have ..

VV ( various)
URP
S365
IMR various but not suitable

Scarcity of choice here


Cartridge          : .300 Win. Mag.(@)
Bullet            : .308, 165, Hornady BTSP 3045
Useable Case Capaci: 83.396 grain H2O = 5.415 cm³
Cartridge O.A.L. L6: 3.340 inch = 84.84 mm
Barrel Length      : 24.0 inch = 609.6 mm


My specs ..
Using
LAPUA Scenar 185gr 33.14mm
Norma cases
94.42 H2O ( measured )
L3 = 66.45 ( Case )
L6 = 88mm  (Cartridge )
24.0 inch barrel

I will cross check your results with mine
]]> Reloading Methodology Newton https://systemz.online/reloading-methodology/imr-4831-where-to-find/#post-7583 Re: IMR 4831 - where to find ? https://systemz.online/reloading-methodology/imr-4831-where-to-find/#post-7582 Thu, 05 Mar 2026 00:15:24 +0000 Here are a few choices that might be easier to source.

Cartridge          : .300 Win. Mag.(@)
Bullet            : .308, 165, Hornady BTSP 3045
Useable Case Capaci: 83.396 grain H2O = 5.415 cm³
Cartridge O.A.L. L6: 3.340 inch = 84.84 mm
Barrel Length      : 24.0 inch = 609.6 mm

Predicted Data for Indicated Charges of the Following Powders.
Matching Maximum Pressure: 57000 psi, or 393 MPa
or a maximum loading ratio or filling of 100 %
These calculations refer to your specified settings in QuickLOAD 'Cartridge Dimensions' window.
C A U T I O N : any load listed can result in a powder charge that falls below minimum suggested
loads or exceeds maximum suggested loads as presented in current handloading manuals. Understand
that all of the listed powders can be unsuitable for the given combination of cartridge, bullet
and gun. Actual load order can vary, depending upon lot-to-lot powder and component variations.
USE ONLY FOR COMPARISON !

76 loads produced a Loading Ratio below user-defined minimum of 80%. These powders have been skipped.
Powder type          Filling/Loading Ratio  Charge    Charge  Vel. Prop.Burnt P max  P muzz  B_Time
                                      %    Grains    Gramm  fps    %      psi    psi    ms
---------------------------------  -----------------------------------------------------------------
Alliant Reloder-26 *C              98,1    81,1    5,25    3186  100,0    57000  13440  1,159  ! Near Maximum !
Norma MRP *C                        98,8    79,3    5,14    3157    99,4    57000  13494  1,155  ! Near Maximum !
ReloadSwiss RS 70 *C                95,7    78,4    5,08    3149    99,7    57000  13116  1,140  ! Near Maximum !
IMR 7828 SSC                        99,2    78,4    5,08    3135    97,4    57000  13287  1,140  ! Near Maximum !
ReloadSwiss RS 60 *T                89,4    72,1    4,67    3133  100,0    57000  12034  1,146  ! Near Maximum !
Vihtavuori N560 *C                100,0    78,5    5,09    3130    96,7    56104  13618  1,158  ! Near Maximum !
ADI AR 2213                        100,0    77,7    5,04    3115    97,2    56709  13116  1,141  ! Near Maximum !
Elcho 17                            88,3    71,2    4,62    3106  100,0    57000  11945  1,154  ! Near Maximum !
Alliant Reloder-17 *T              88,3    71,2    4,62    3106  100,0    57000  11945  1,154  ! Near Maximum !
Alliant Reloder-16 *C *T            93,1    69,7    4,52    3105  100,0    57000  11971  1,144  ! Near Maximum !
Accurate MAGPRO                    100,0    81,7    5,30    3103    95,0    55347  13594  1,174  ! Near Maximum !
Raufoss RA15 *C                    100,0    77,7    5,04    3102    98,3    55711  13148  1,168  ! Near Maximum !
Alliant Reloder-22 *C              100,0    77,7    5,04    3102    98,3    55711  13148  1,168  ! Near Maximum !
Bofors RP5/NP ~approximation      100,0    77,7    5,04    3102    98,3    55711  13148  1,168  ! Near Maximum !
Vihtavuori N555 *C*T                99,2    74,8    4,85    3090  100,0    57000  12149  1,182  ! Near Maximum !
ADI AR 2209                        96,9    74,1    4,80    3085    98,3    57000  12515  1,143  ! Near Maximum !
PB Clermont PCL 518                93,7    74,4    4,82    3081    99,6    57000  12343  1,158  ! Near Maximum !
Alliant Reloder-19 *C              97,3    74,8    4,85    3080    98,3    57000  12567  1,152  ! Near Maximum !
ReloadSwiss RS 62                  91,6    73,8    4,78    3080  100,0    57000  12085  1,172  ! Near Maximum !
PB Clermont PCL 511                90,0    73,7    4,78    3079    99,7    57000  12266  1,159  ! Near Maximum !
Ramshot Magnum                    100,0    83,7    5,43    3078    98,8    55112  12662  1,166  ! Near Maximum !
Ramshot Hunter                      93,0    73,8    4,78    3077    99,7    57000  12249  1,159  ! Near Maximum !
Hodgdon H414                        87,8    71,4    4,62    3076    99,4    57000  12282  1,160  ! Near Maximum !
Winchester 760                      87,8    71,4    4,62    3076    99,4    57000  12282  1,160  ! Near Maximum !
Bofors RP14 ~approximation          98,1    75,4    4,89    3073    98,3    57000  12478  1,153  ! Near Maximum !
Somchem S365                        94,6    72,3    4,69    3072  100,0    57000  11427  1,169  ! Near Maximum !
Norma URP *C                        92,5    70,3    4,56    3059  100,0    57000  11762  1,165  ! Near Maximum !
Bofors RP19 ~approximation          92,5    70,3    4,56    3059  100,0    57000  11759  1,165  ! Near Maximum !
Norma 204 *C                        92,4    73,3    4,75    3058    98,1    57000  12249  1,152  ! Near Maximum !
Bofors RP4 ~approximation          95,4    73,3    4,75    3058    98,1    57000  12249  1,152  ! Near Maximum !
Raufoss RA4                        95,4    73,3    4,75    3058    98,1    57000  12249  1,152  ! Near Maximum !
Vihtavuori N550 *C                  89,8    70,5    4,57    3058  100,0    57000  11884  1,169  ! Near Maximum !
Accurate 4350                      91,8    70,6    4,57    3055  100,0    57000  11764  1,184  ! Near Maximum !
Hodgdon H4831 SC *T                98,7    76,7    4,97    3054    96,5    57000  12351  1,149  ! Near Maximum !
Hodgdon CFE223 *C                  83,7    70,2    4,55    3053  100,0    57000  11642  1,161  ! Near Maximum !
Somchem S385                        97,6    75,9    4,92    3044    99,0    57000  12068  1,173  ! Near Maximum !
IMR 4831                            97,1    71,5    4,63    3041  100,0    57000  11521  1,174  ! Near Maximum !]]> Reloading Methodology Tripodmvr https://systemz.online/reloading-methodology/imr-4831-where-to-find/#post-7582 IMR 4831 - where to find ? https://systemz.online/reloading-methodology/imr-4831-where-to-find/#post-982 Wed, 04 Mar 2026 23:35:32 +0000
IMR4831 .. NOT H4831SC
This powder looks like it will give the best results in my 300WM
Seems to be scarce though - everyone out of stock

Powder of choice in the 20mm - all supplies gone to the military ?

]]> Reloading Methodology Newton https://systemz.online/reloading-methodology/imr-4831-where-to-find/#post-982