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Fixing the Ruger® Mini 14/30 Bolt to Shoot Imported Ammunition
by Roy Seifert

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Disclaimer:  This article is for entertainment only and is not to be used in lieu of a qualified gunsmith.  Please defer all firearms work to a qualified gunsmith.  Any loads mentioned in this article are my loads for my guns and have been carefully worked up using established guidelines and special tools.  The author assumes no responsibility or liability for use of these loads, or use or misuse of this article.  Please note that I am not a professional gunsmith, just a shooting enthusiast and hobbyist, as well as a tinkerer.  This article explains work that I performed to my guns without the assistance of a qualified gunsmith.  Some procedures described in this article require special tools and cannot/should not be performed without them.

Warning:  Disassembling and tinkering with your firearm may void the warranty.  I claim no responsibility for use or misuse of this article.  Again, this article is for entertainment purposes only!

Tools and firearms are the trademark/service mark or registered trademark of their respective manufacturers.


Many years ago I purchased a Ruger® Mini-14 in .223 Remington caliber.  The manual that came with it stated point-blank that I should not use imported ammunition with this rifle.  I soon found out why.

After firing only 30 rounds of Russian .223 ammunition, the rifle would no longer fire.  Upon examination, I found the firing pin was jammed.  I disassembled the bolt and found it filled with small, round, brass disks!  I removed the disks, fired another 30 rounds, and again, the firing pin was jammed because the bolt was filled with those brass disks.  I recovered some spent shells and discovered each primer had a neat, round hole in the center of the primer that corresponded with the brass disks I found inside the bolt. 

I carefully examined the bolt face and found a sharp burr around the firing pin hole (probably raised during the machining process when Ruger® drilled the hole).  I also discovered that the firing pin was protruding too far in front of the bolt face.  The long firing pin would create a too-deep indentation in the primer.  During recoil the case head was pressed against the bolt face, where the burr would cut out the center.  These two conditions would cause the center of the primer to be cut out into a round disk, and the blowback would cause that disk to be blown into the bolt body through the firing-pin hole.  Enough disks blown into the bolt body would jam the firing pin.

The fix was easy.  I removed the extractor and firing pin.  Then I used a narrow 400-grit stone to remove the burr around the firing pin hole.  Note in the photo the white ring around the firing pin hole.  This indicates I removed the burr.  I then shortened the firing pin by 0.010”.  I did this by rubbing the end of the firing pin on a smooth stone being careful to maintain a round end.  Now I could fire my Mini-14 all day using imported ammunition with no failures or jamming.

Ruger® has since rewritten their manuals and removed this restriction.  However, I recently purchased a Mini-30 and the bolt still had a burr, which I polished smooth to avoid any problems with imported ammunition.

 

 
   © Copyright 2008 Roy Seifert.