375 Mystery Bullet???

[Jim Finn]

The photo shows one of the 300 gr mystery 375 cal bullets (right) next to a 300 gr Barnes Triple shock (left). At the bottom is the base showing exposed lead and a pretty darn thick jacket. I baught 100 of these at the Wasilla gunshow. The guy selling them didn't know too much about them other than they seem to have a steel jacket plated with copper. A magnet will pick them up and it looks like steel when I have scraped away the copper.
I can't find any information on a steel jacketd bullet in any of my reloading manuals. Is this a discontinued Hornady?
Can anyone identify this for me? I would think I'd have to back off on loads for copper jacketed bullets as a steel jacket would most likely increase pressure. Is that true?
Thanks in andvance.
Jim

[Hewey 260]

I have half a box of exactly the same bullet with base and the thick jacket you describe and show in picture. I aquired them from my grandfathers reloading stuff. For what it's worth the box they are in is a hornady box with 300 GR .375 F.M.J printed on it. Lot #1060. Mine stick to a magnet too. Don't know if that helps you at all.

[Hewey 260]

I also just went to my bench and looked at one of the old reloading books that I got from my grandfather too. It's a Hornady reloading handbook published in 1967 that has reloading data for those bullets. If you interested I can scan the pages and send to you or copy them and mail it.

[Jim Finn]

Thanks Hewey 260!
If it isn't too much trouble, I would like to get a look at the reloading data you have. There is no rush at all as the rifle I'll use these in is still being put together. It will be a 375 Ruger on an Interarms Mark X action. Can you save the scanned page as a file? if so, you could just e-mail it to me at ( jfinn@mtaonline.net ). I mostly want to get an idea how much I should adjust cooper jacketed bullet loads when I start loading these.
Take care
Jim

[Hewey 260]

Not a problem. Happy to help.

[Murphy]

It is a Hornady 300 grain RN solid, which is a steel clad, copper covered FMJ. I have several of them also and the Hornady manual I have uses the same data for both solids and soft points. They are currently manufactured.

70.0 grains of RL-15 or 66.0 grains of H4895 will make a good load.

[Jim Finn]

That should do it!!!

Thanks Murphy,
That is all I really need to know. When I get the rifle together, I'll start of cautiously using the current Hornady data.
Hewey, seems there is no need for you to go to all that trouble. Thanks so much for being willing to do it though!!
Jim

[Jim Finn]

This is the reply I got directly from Hornady:

++++++++++++++++++++++++++++++++++++++++++++++++++ +++++
Jim, It sounds like you have a box of our dangerous game solids. They
are copper clad steel jacketed bullets. They perform very well with no
expansion. The standard load data for the 300 gr. bullets can be used.
thanks
++++++++++++++++++++++++++++++++++++++++++++++++++ ++++++

I think that settles it.
Jim