338-378 Weatherby

Handload Data

Warning: Bullet selections are specific, and loads are not valid with substitutions of different bullets of the same weight. Variations in bullet length will alter net case capacity,  pressure and velocity. Primer selection is specific and primer types are not interchangeable. These are maximum loads in my firearms and may be excessive in others. All loads should be reduced by 5% as a starting point for development where cartridges have greater than 40 grains in capacity and 10% for cartridges with less than 40 grain capacity following safe handloading practices as represented in established mainstream reloading manuals. Presentation of these loads does not constitute a solicitation for their use, nor a recommendation.

Cartridge – 338-378 Weatherby Magnum
Firearm Weatherby Mark V Accumark
Barrel Length 26.00″
Min – Max Case Length 2.500″ +0.000″/-0.020″
Min – Max COL 3.215″ – 3.340″
Primer CCI 250
Bullet Diameter 0.3390″ +0.000″/-0.0030″
Reloading Dies Redding
Bullet Type Bullet
Weight
Grains
Net H2O
Grains
Capacity
C.O.L.” Powder Type Powder
Charge
Grains
Muzzle
Velocity
FPS
Muzzle
Energy
ft/lbs
Barnes TTSX 160 128.4 3.750 AA MagPro 124.0 3567 4520
Barnes TTSX 160 128.4 3.750 Alliant Reloder 23 117.0 3524 4459
Barnes TTSX 160 128.4 3.750 Hodgdon H4831 117.0 3521 4404
Nosler AccuBond 180 127.4 3.700 AA MagPro 121.0 3437 4721
Nosler AccuBond 180 127.4 3.700 Alliant Reloder 26 118.0 3447 4748
Nosler AccuBond 180 127.4 3.700 IMR 7828 SSC 116.0 3463 4792
Hornady CX 185 124.7 3.750 Alliant Reloder 26 115.5 3407 4769
Hornady CX 185 124.7 3.750 IMR 7828 SSC 113.5 3421 4806
Hornady CX 185 124.7 3.750 RS Magnum 121.0 3350 4611
Hornady SST 200 126.7 3.730 AA MagPro 118.0 3306 4855
Hornady SST 200 126.7 3.730 Hodgdon H1000 119.5 3351 4986
Hornady SST 200 126.7 3.730 RS Magnum 120.5 3320 4894
Speer SP 200 129.5 3.700 Hodgdon H1000 121.0 3348 4978
Speer SP 200 129.5 3.700 IMR 7828 SSC 114.0 3379 5070
Speer SP 200 129.5 3.700 RS Magnum 122.0 3316 4884
Barnes TTSX 210 130.4 3.740 Alliant Reloder 33 128.0 3343 5211
Barnes TTSX 210 130.4 3.740 Hodgdon H1000 116.0 3285 5032
Barnes TTSX 210 130.4 3.740 RS Magnum 116.5 3241 4898
Nosler Partition 210 127.7 3.700 Alliant Reloder 33 131.5 3356 5251
Nosler Partition 210 127.7 3.700 Hodgdon H1000 119.5 3304 5091
Nosler Partition 210 127.7 3.700 IMR 7828 SSC 112.0 3317 5130
Barnes TTX 225 120.7 3.740 Alliant Reloder 33 125.0 3259 5307
Barnes TTX 225 120.7 3.740 Hodgdon H1000 113.5 3201 5118
Barnes TTX 225 120.7 3.740 IMR 7828 SSC 106.5 3216 5166
Speer SPBT 225 126.8 3.670 Alliant Reloder 33 129.0 3269 5340
Speer SPBT 225 126.8 3.670 Hodgdon Retumbo 121.5 3226 5200
Speer SPBT 225 126.8 3.670 IMR 7828 SSC 109.5 3214 5160
Hornady Interlock 250 124.8 3.730 AA MagPro 111.0 3079 5262
Hornady Interlock 250 124.8 3.730 Alliant Reloder 33 124.5 3127 5427
Hornady Interlock 250 124.8 3.730 Hodgdon Retumbo 117.5 3082 5273
Speer Grand Slam 250 125.0 3.610 Alliant Reloder 33 124.5 3124 5418
Speer Grand Slam 250 125.0 3.610 Hodgdon Retumbo 117.5 3092 5307
Speer Grand Slam 250 125.0 3.610 RS Magnum 113.5 3012 5035
Swift A-Frame 275 121 3.640 Alliant Reloder 33 111.0 2893 5111
Swift A-Frame 275 121 3.640 IMR 7828 SSC 95.0 2846 4954
Swift A-Frame 275 121 3.640 Hodgdon Retumbo 105.5 2878 5059

Comments appearing below are posted by individuals in a free exchange, not associated with Real Guns. Therefore RGI Media takes no responsibility for information appearing in the comments section. Reader judgement is essential.

Email Notification

Leave a Comment