375 HH and lead cast bullets

[carpediem]

Greetings from Alberta:

I recently acquired a 375 HH in a BRNO and I would like to use lead cast bullets with this rifle for hunting moose, whitetail and mule deer.

Is anyone out there using lead cast bullets in a 375 HH?  What kind of mold are you using?  What is the bullet weight and design?  What type of alloy are you using and are you using gas checks?  How fast are you driving the bullet?  How well does the bullet work at killing large game?  Any other info would be appreciated.

Kindest regards,

[Larry Gibson]

carpediem

If you can get the "Cast Bullet Supplements" from the NRA they would provide you with a wealth of info on cast bullets, particularly the .375.  There is an excellent article on using cast bullets in the .375 in Africa.

I have been working with Lyman 377449 which is a GC design.  The bullets weigh 270 gr gas checked and Javlina lubed with the alloy I use.   I shoot this bullet at about 1800 fps just for practice.  I cast these out of WWs and have been using AA5744.  For hunting I use new "magnum" shotgun shot (size doesn't matter) that contains about 5% antimony.  I drop these out of the mould into a large coffee can of cold water to harden them.  This anitimony/lead alloy will harden to sustain about 2200 fps and yet give expansion instead of shattering like antimony/tin/lead alloys.  I have been working up a load with 4895 and a dacron filler that shows real promiss at 2100 fps.  While not up to standard .375 H&H velocities it exceeds the power of the .375 Winchester.  I wouldn't have any problem hunting with it.

For grouse, ptarmigan and hares try the Hornady .375 RB tumbled lightly in Lee Alox lube over 4 gr of Bullseye.  It will run around 900 fps and is accurate enough for these small game out to 50 yards.  And they are just plain fun to shoot.

Larry Gibson

[carpediem]

Thanks LMG for the info.

When working up your loads, are you using a recipie or are you just picking a powder and guessing?

What does dropping the bullet into cold water do to the bullet to make it harder than slow cooling?

Kindest regards,

[Larry Gibson]

carpediem

"When working up your loads, are you using a recipie or are you just picking a powder and guessing?"

I have been loading and shooting cast bullets for almost 40 years.  I have numerous references and loading manuals from years past that give "recipies" not found in most manuals today.  It is my experience that 4895 is an excellnt powder for heavy cast bullets per caliber when you want performance in the 1800+ range.  A rule of thumb used by the old timers and recently reiterated by Hodgdon was a starting load for 4895 is about 50-60% of case capacity.  I have found if I start at 60% and work up I am pretty close.  

"What does dropping the bullet into cold water do to the bullet to make it harder than slow cooling?"

Dropping the hot bullet into cold water tempers or hardens the metel.  Many erroniously believe one hardens bullets so the bullet will hold the rifling better.  This is not the case.  We harden bullets to prevent "set back" , severe over obturation or deformation of the bullet from acceleration.  In otherwords the nose of the bullet wants to stay at rest while the ass end is getting a kick start from the gas pressure.  The bullet squishes (obturates) forward filling out the throat or into what ever room it has.  Many times the nose is bent crooked or obturates out of shape by this rapid accelleration also.  All this excessive obturation is not conducive to accuracy.  Hardening the bullet alloy to reduce this excessive obturation helps.  

The use of slower powders with slower pressure curves also prevents the "sudden" acceleration that the faster powders cause and thus produce less bullet upset or obturation.

Larry Gibson

[carpediem]

:-D Thanks for the info LMG.  I will try working up some loads with what you have suggested.

Kindest regards,

Carpediem