Loading for Short Magnum

[Californio]

[StraightShooter]

Yeah, i load for my 300 wsm but it took me a while to get the shoulder bumped back correctly. The wsm's are more finnicky because of the sharper angle of the shoulder. The best thing to do is get a case gauge and use some factory ammo and some calipers for comparison.

[r08ert209cali]

i've reloaded 270 wsm with no problems thus far

[Californio]

Are you guys getting factory velocity with your reloads?

[StraightShooter]

I actually dont have a chronograph but the trajectories are the same with the same weight bullets so I am assuming yes or close to the same.

[ar15barrels]

There are a LOT more powders available to ammo makers than there are to reloaders.
The powders we buy as reloaders are called "cannister" because they are supposed to be similar enough from lot-to-lot and year-to-year to use the same loading data.
The factories buy powder by the lot and they can develop a specific load for one specific lot of powder and then re-develop when a new batch of powder is used.

Most factory loads are using non-canister powders selected or developed for a specific cartridge/bullet combination.
It's often not possible to meet the same velocity with cannister powders.
Quickload will teach you a lot about powders and help choose the fastest one for a specific cartridge/bullet combination.

As an example, here is a 300wsm pass for a 180gr winchester failsafe bullet:

Cartridge          : .300 Win Short Mag [WSM]
Bullet             : .308, 180, Winchester FailSafe FS30
Cartridge O.A.L. L6: 2.860 inch or 72.64 mm
Barrel Length      : 24.0 inch or 609.6 mm

Predicted Data for Indicated Charges of the Following Powders.

Matching Maximum Pressure: 64500 psi, or 444 MPa

or a maximum loading ratio or filling of 105 %

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 !

72 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
---------------------------------  -----------------------------------------------------------------
ADI AR 2213                        105.0     69.8     4.52    3041    97.9    64500   13832   1.116  !DANGEROUS LOAD-DO NOT USE!
Vihtavuori N560                    105.0     70.2     4.55    3036    97.2    61530   14332   1.146  ! Near Maximum !
ADI AR 2209                        101.4     66.7     4.32    3010    98.8    64500   13092   1.122  !DANGEROUS LOAD-DO NOT USE!
Ramshot Hunter                      97.7     66.7     4.32    3007    99.9    64500   12793   1.136  !DANGEROUS LOAD-DO NOT USE!
Winchester 760                      95.5     64.5     4.18    3003    99.7    64500   12756   1.138  !DANGEROUS LOAD-DO NOT USE!
Norma MRP                          105.0     69.4     4.50    3000    99.3    58055   13972   1.178  ! Near Maximum !
Somchem S365                       102.8     65.4     4.24    2999   100.0    64500   11822   1.143  !DANGEROUS LOAD-DO NOT USE!
IMR 7828 SSC                       105.0     69.1     4.48    2996    97.3    60331   13744   1.150  ! Near Maximum !
IMR 4350                            99.8     63.2     4.10    2993    99.9    64500   12454   1.134  !DANGEROUS LOAD-DO NOT USE!
Vihtavuori N550                     95.5     63.8     4.13    2986   100.0    64500   12313   1.147  !DANGEROUS LOAD-DO NOT USE!
Raufoss RA4                        103.1     66.0     4.28    2982    98.7    64500   12803   1.132  !DANGEROUS LOAD-DO NOT USE!
Norma 204                          100.9     66.0     4.28    2982    98.7    64500   12803   1.132  !DANGEROUS LOAD-DO NOT USE!

Now look at how the powders switch places in how well they perform when you change to a 150gr Nosler Partition Gold:

Cartridge          : .300 Win Short Mag [WSM]
Bullet             : .308, 150, Nosler PartGold 52200
Cartridge O.A.L. L6: 2.860 inch or 72.64 mm
Barrel Length      : 24.0 inch or 609.6 mm

Predicted Data for Indicated Charges of the Following Powders.

Matching Maximum Pressure: 64500 psi, or 444 MPa

or a maximum loading ratio or filling of 105 %

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 !

67 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
---------------------------------  -----------------------------------------------------------------
Ramshot Hunter                     100.6     71.3     4.62    3273    99.4    64500   13907   1.049  !DANGEROUS LOAD-DO NOT USE!
Winchester 760                      98.3     69.0     4.47    3269    98.8    64500   13831   1.051  !DANGEROUS LOAD-DO NOT USE!
ADI AR 2209                        104.1     71.2     4.61    3265    97.4    64500   14038   1.038  !DANGEROUS LOAD-DO NOT USE!
IMR 4350                           102.7     67.6     4.38    3260    99.1    64500   13524   1.047  !DANGEROUS LOAD-DO NOT USE!
Vihtavuori N550                     98.3     68.3     4.42    3257    99.9    64500   13467   1.060  !DANGEROUS LOAD-DO NOT USE!
Somchem S365                       105.0     69.5     4.51    3255   100.0    62269   12901   1.069  ! Near Maximum !
Accurate XMR 4350                  102.5     68.2     4.42    3253    99.9    64500   13267   1.070  !DANGEROUS LOAD-DO NOT USE!
Ramshot BigGame                     99.1     66.3     4.30    3239   100.0    64500   12772   1.054  !DANGEROUS LOAD-DO NOT USE!
Norma 204                          103.7     70.5     4.57    3239    97.2    64500   13732   1.046  !DANGEROUS LOAD-DO NOT USE!
SNPE Vectan SP 11                   96.6     66.4     4.31    3238   100.0    64500   12756   1.054  !DANGEROUS LOAD-DO NOT USE!
Hodgdon H4350                      104.2     70.2     4.55    3232    96.6    64500   13657   1.042  !DANGEROUS LOAD-DO NOT USE!
IMR 4895                            94.4     61.5     3.98    3232   100.0    64500   11900   1.039  !DANGEROUS LOAD-DO NOT USE!

[Californio]

Randall,

Thanks for the tables.

If I am reading correctly, those loads are all compressed to get 3200fps. The 300 RUM I was playing with a few weeks ago was doing 3200fps with a 180 SST without having to compress the load of 88+gr of IMR. and .6 moa.

All factors being the same, am I correct to assume that a full length case is going to be easier to reload and I won't have to deal with compressed loads?

[-hanko]

Randall,

Thanks for the tables.

If I am reading correctly, those loads are all compressed to get 3200fps. The 300 RUM I was playing with a few weeks ago was doing 3200fps with a 180 SST without having to compress the load of 88+gr of IMR. and .6 moa.

All factors being the same, am I correct to assume that a full length case is going to be easier to reload and I won't have to deal with compressed loads?

Yes. Gun makers/ammo makers are sleeping together with the newer sm's, ssm's, rum's, etc. Neither publish reload info like the older, and still just-as-good calibers. Until that happens, they're smart enough to know they'll bend you over with prices on factory ammo. 'Tis the nature of the beast.

That's enough to make me pass on short magnum offerings at this time.

-hanko

[Fjold]

I don't know, I load the my 300 WSM for accuracy at whatever velocity it happens to get to and I've never shot a factory load in it to compare against.

It doesn't matter to me if the bullet is going 2900 or 3100 fps, at hunting distances the animal isn't going to know the difference if you manage to hit it in the correct place.

If I need more power I use my 375 H&H.