Ruger 7.62x39 rifles bore size.

Discussion in 'Ruger' started by Mark, Oct 21, 2002.

  1. Mark

    Mark Guest

    I recently requested information from Davidson Guns regarding the actual bore diameter of the Mini Thirty and Model 77 rifles of this caliber. I'm considering reloading, and had heard different stories on the true bore size. The following was the reply I received today:

    Dear Mr. Phelps,

    Thank you for your inquiry at! Ruger's groove
    diameter for the 7.62X39 caliber cartridge for either the Mini-30 or model
    77's is .3100 - .3115 according to their engineering dedpartment. This is a
    compromise diameter designed to shoot either the .308 or .313 diameter ammo
    that is available. A .311 diameter bullet would be my choice for handloading
    applications if available.

    I hope this helps!


    Rebecca L. Gridley
    Web Administrator
  2. jpaulghetto

    jpaulghetto Guest

    I think Davidsons is giving bad info. Somthing does'nt jive with my info. Both , Sierra and Hornady reloading manuals indicate a ..308 bore diameter for the mini-thirty. Perhaps brand new models have .311 bore but older models do not.Too us Reloaders of this fine cartridge, it would be of intrest to know serial #s as to the larger diameters introduction. It was my understanding that bullet makers tried to cover both bore diameters with the .310 bullet. Bottom line, slug your bore before handloading for the mini-thirty!!

  3. TERRY8mm

    TERRY8mm Guest


    the Rugers have the same bore as all of their other .30 chamberings.

    load 'em with lighter .308 weights and they shoot just fine.
  4. Mark

    Mark Guest

    Anyone have any experience reloading with 110 grain bullets in 7.62x39?