Project Rifle – .375 H&H Magnum

By Mark V. Lonsdale

The five month project rifle came to completion yesterday with the arrival of the UPS truck – a custom .375 H&H big game hunting rifle. This began back in June with the order of a Stiller’s Predator action, Bartlein #4 Bull Sporter barrel, a McMillan Tactical Hunter stock, and a Bix’N Andy Dakota trigger.

For anyone planning a custom build, it is recommend to order all the components at the same time since manufacture lead time and delivery can vary based on availability, demand, and time of year.

Custom .375 H&H Magnum built on a Stiller’s Predator action, running a 24″ Bartlein #4 Bull Sporter with APA brake, in a McMillan Adjustable Tactical Hunter stock with McMillan 4″ bipod rail. Trigger is the superb Bix’N Andy Dakota and bottom metal includes a Wyatt’s extended magazine box.
McMillan Tactical Hunter stock with adjustable cheek rest
Stiller’s Predator action which is similar to their TAC300 action but machined to accept the longer Wyatts magazine box. This allows for running longer, heavier bullets with longer cartridge overall lengths. The Leupold Mark 4 M5 will be used for initial testing until a more suitable hunting scope is added.
The Bix’N Andy Dakota trigger is ideal for tactical and hunting rifles with a set range from 1 to 4 pounds. One added feature is that the trigger can be easily adjusted with a single screw while still in the stock.

Break-in and testing will begin this week with an assortment of bullets, powders, and loads to include Hornady 270 grain Round Nose, Hornady 250 grain GMX, and Speer 270 grain BTSP, with Sierra and Barnes next week. Powders will include IMR 4064, Varget, IMR 4350, and H4350.

Most of the rounds are currently loaded to close to SAAMI COAL spec of 3.600″ but .375 H&H chamber throats are actually cut quite long, allowing for rounds to be loaded out to 3.750+” depending on the ogive of the bullet. Using a Hornady Lock N’ Load, some bullets were touching the lands at 3.787″-3.878″ and the Sierra 350 grain SMK was 4.000″. This will make for some interesting testing to see which bullets like a running start of 0.200″ and which perform better with less jump closer to 0.020″

Stay tuned for updates later this week….


About Mark V

Dedicated shooter, seeker, traveler, teacher, trainer, educator
This entry was posted in Uncategorized. Bookmark the permalink.

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s