400: 40 Caliber Cartridges: The Ultimate Guide

400: 40 Caliber Cartridges: The Ultimate Guide

Author: John McAdams December 4, 2025 Duration: 1:11:41

I discuss all of the 40 caliber SAAMI standardized rifle cartridges (plus one other noteworthy CIP round) in this episode. As always, I'll talk about their history, design characteristics, performance specs, their strengths and weaknesses, and their recommended uses in detail. Where appropriate, I'll also share some personal anecdotes involving these rounds as well as some observations involving various cartridges by noteworthy gun writers as well.

Cartridges covered: 44-40 WCF, 45-70 Government, 577/450 Martini-Henry, 405 Winchester, 44 Remington Magnum, 444 Marlin, 450 Marlin, 450 Bushmaster, 400 Legend

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Resources

44-40 Profile | Winchester 1873 44-40 Gel Test

.577/450 Martini-Henry Rifle & Cartridge: History, Ballistics, Hunting & Gel Test Results

African Rifles & Cartridges by John Taylor

African Game Trails by Theodore Roosevelt

To Ride, Shoot Straight, And Speak The Truth by Jeff Cooper

Episode 286: 30 Caliber Cartridge Roll-Up

Episode 291: 270 Caliber Cartridge Roll-Up

Episode 297: 9.3mm and 375 Caliber Cartridge Roll-Up

Episode 300: 40 Caliber Safari Cartridge Roll-Up

Episode 328: 25 Caliber Cartridge Roll-Up

Episode 329: 50, 60, & 70 Caliber Safari Cartridges With Kevin Robertson

Episode 338: 338 Caliber Cartridge Roll-Up

Episode 345: 7mm Cartridge Roll-Up

Episode 345: The "Other" 30 Caliber Cartridges: 303 British, 7.x62x54R, etc.

Episode 358: 35 Caliber Cartridge Roll-Up

Episode 398: 6.5mm Cartridge Roll-Up

Episode 399: 8mm/32 Caliber Cartridge Roll-Up


John McAdams hosts the Big Game Hunting Podcast, a conversation grounded in the realities of pursuing game across continents. Each episode feels like a detailed campfire talk, moving from the technical specifics of terminal ballistics and caliber selection to the raw, unforgettable narratives from the field in Africa, North America, and beyond. McAdams brings together a global community, with voices ranging from seasoned industry professionals to fellow hunters who call in with their own experiences. The focus is always on practical knowledge and authentic stories, stripping away any pretense to get to the heart of what hunters actually want to discuss. By sharing his own journey of learning and improvement, McAdams creates a space where curiosity and respect for the wilderness drive the dialogue. Tuning into this podcast means joining a serious yet accessible exchange where the complexities of the hunt are explored without filter. New conversations are released every Thursday, offering a consistent dose of insight and camaraderie for anyone passionate about the pursuit.
Author: Language: English Episodes: 100

Big Game Hunting Podcast - Hunting Africa, North America, & More!
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