30 on 375 ruger case.

Discussion in 'Long Range Hunting & Shooting' started by ann brezinski, Feb 3, 2014.

  1. ann brezinski

    ann brezinski Well-Known Member

    Feb 12, 2008
    I have since seen on my computer a sight that shows a 300 ruger factory magnum.i assume it is basicly the 30 375 ruger case.
    am I right about this.
  2. WildRose

    WildRose Well-Known Member

    Feb 3, 2011
    That's the 300 RCM. Yes it's based on the same case but cut down about a half inch so it will work on the shorter actions.

    .300 Ruger Compact Magnum - Wikipedia, the free encyclopedia

    You're giving up considerable case capacity and performance as a result vs going with the full length 375 case necked down.
  3. AZShooter

    AZShooter Well-Known Member

    Dec 12, 2005
    The 300 RCM and 338 RCM share the same shoulder diameter and angle as the 375 Ruger with shorter bodies. The beauty of this is you COULD use 338 and 300 RCM dies to neck down the 375 Ruger case to 30 cal.

    I had a box of 375 Ruger brass sitting on a shelf ever since it was introduced. Last year I decide to see if I could size it down to 7mm with existing dies.

    I already owned a some dies for the 338 RCM: Hornady FL die set and a Whidden FL/bushing die.

    Start reducing the neck diameter by using a 375 Ruger FL die with sizer ball removed. Then move to the 338 RCM FL die. Just don't go to far and size the body.

    I used other dies to continue but I would suggest the 300 RCM FL die would be the inexpensive way to get to 30 cal.

    Use the 300 RCM FL die for subsequent sizings and a 375 Ruger FL die for any shoulder/body taper sizings. While I am using the whidden bushing/fl die for my sizing of the necks I use the 375 Ruger FL die for the body of my 7mm/375 and it has worked just fine.

    I suppose you could talk to Whidden and have them make a 300/375 Ruger FL/bushing die.

    As for seating with the 7mm/375 you could do the same thing I did. I used the chamber reamer to open up the sliding tube in a Redding 7 Rem mag competition seating die. You could do same with a 300 win mag or similar comp seater.

    The 30/375 Ruger is very appealing. Brass is readily available and it would perform somewhere between the 300 win mag and a 300 RUM. It has been on list of to do cartridges for a while now.
    Maybe when my 300 RUM barrel wears out I'll switch.