• Light Primer Strikes

    Occasionally we get a question on the forum from someone who is experiencing ignition problems with their Savage 110-series rifle. The below information was assembled to help troubleshoot and resolve those issues. Note that the majority of this information is only applicable to Savage models from the 110-Series that have the adjustable firing pin assembly.

    Firing pin protrusion should be set between .035" -.045" with anything more than .050 being excessive and counterproductive. It has been proven that as little as .020 firing pin travel will ignite the primer once the firing pin makes contact with the primer. This is contingent on a properly sized case with a properly seated primer.

    If your bolt and firing pin have been assembled correctly, there are basically only three reasons for a light strike.

    The first being improperly seated primers. If the primers are not seated properly, they will move inward when the firing pin strikes driving the primer into the pocket. This movement absorbs the energy the firing pin needs to ignite the primer.

    The second being a dirty firing pin/bolt assembly where grime and or gunk will restrict the movement of the firing pin resulting in light primer strike. Poor choice of lubricants or pierced primers can be the culprit.

    Third incorrectly sized brass. Measure base to shoulder dimensions when setting up your dies. That dimension is critical to the correct and safe function of your rifle. Over sized brass or brass that has had the shoulder bumped back too far can cause issues. You might have a fail to fire or if it does fire, the primer is backed out. A situation where oversized brass has been pushed forward into the chamber and the pressure inside the case forces the primer partially out of the pocket. If this condition is repeated you may see case head separation in the near future if you have not already. If you reload, get tools to check your sizing die adjustment. If you are good you will learn to feel when the shoulder is bumped as you adjust the die down.

    All things considered if you still think there is a problem with your bolt/firing pin....

    When inspecting or rebuilding your bolt and firing pin assembly, measure the compressed spring length and document. Return to as close of a setting as possible when reassembling. Ensure the cocking piece pin is not bottoming out at the lower end of the cocking ramp. There should be a small amount of movement side to side. This will ensure you are getting close to .250" lift of the firing pin. If you move your bolt handle 45* before you feel cocking effort you may have lost half of your firing pin travel from improper adjustment. Turn the cocking piece to down making the compressed spring length shorter and increase the firing pin travel.

    Keep it clean. Use a fine light lubricant if you must. I spray with Kroil and wipe of the access. It is mostly used for a rust inhibitor. Don't use a lubricant that attracts dirt or evaporates becoming sticky and gummy. Make sure the Firing pin assembly slides easily with no friction or drag.

    If you back off the cocking piece thinking that it reduces the bolt lift by changing the spring pressure/preload, you are mistaken. You have only reduced the amount the firing pin will fall when the trigger is pulled. For every full turn you have shortened the Firing pin travel by .036" reducing the energy for igniting the primer. The preload of the spring is not effected by the position of the cocking piece it is effected by the position of the cocking piece sleeve, held in position by the BAS. When the bolt is cocked it further compresses the spring 1/4", the approximate amount the firing pin travels.

    Your chances of light primer strikes due to a problem with your rifle are non existent if you follow these guidelines.


    Trigger/sear hand-off or timing effects firing pin travel and how the bolt closes also. That, bolt lift kits and other Savage firing pin issues are topics for another day.

    DISCLAIMER:
    The information contained in this article and/or the attached video are for educational purposes only. Should you choose to use this information to alter or modify your firearm you do so of your own accord. In doing so you accept full responsibility for any adverse affects, damages, injuries and/or death that may occur as a result.

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    This article was originally published in forum thread: Light Firing Pin Strikes started by Robinhood View original post
    Comments 14 Comments
    1. DeltaNu1142's Avatar
      DeltaNu1142 -
      New to this... but how does this section relate to the bolt lift kit offered by Nat Lambeth (and others)?

      If you back off the cocking piece thinking that it reduces the bolt lift by changing the spring pressure/preload, you are mistaken. You have only reduced the amount the firing pin will fall when the trigger is pulled. For every full turn you have shortened the Firing pin travel by .036" reducing the energy for igniting the primer. The preload of the spring is not effected by the position of the cocking piece it is effected by the position of the cocking piece sleeve, held in position by the BAS. When the bolt is cocked it further compresses the spring 1/4", the approximate amount the firing pin travels.
    1. Robinhood's Avatar
      Robinhood -
      One would have to know the stacked dimensions of the new pieces to determine what the net effect would be on spring tension. To get back to the factory preload you would have no change in the position of the cocking sleeve once the BAS is tightened and the pointed set screw are in the correct position.
    1. DeltaNu1142's Avatar
      DeltaNu1142 -
      Good to know. I'll try to remember to take measurements pre and post.
    1. Kylis-dad's Avatar
      Kylis-dad -
      I'd like to add, Accutriggers, if the rifle is equipped, can cause light primer strikes/misfires. I'd look there first.
    1. Robinhood's Avatar
      Robinhood -
      I'd like to add, Accutriggers, if the rifle is equipped, can cause light primer strikes/misfires. I'd look there first.
      This is one of the reasons this article was posted. Accutriggers do not cause light primer strikes or misfires.

      An Accutrigger with the trigger spring adjusted too low can be easily tripped on accident. This can happen on bolt closing or if the trigger is touched or maybe just a slight bump of the weapon. When this happens the sear will slip from the trigger and the safety blade will stop the sear from releasing the the firing pin. This is how it is designed and is not considered a light strike or a misfire. The firing pin never touches the primer.

    1. SFLEFTY's Avatar
      SFLEFTY -
      First, the SEAR stopping the cocking pin determines the stroke of the firing pin. The only problem the other causes is just low firing pin spring force. I have a bolt with that problem. Yes it misfires. Second, I have seen enough on here through the years to know that some (a few?) Accutriggers have been out of spec enough to cause misfires. No matter how good their QC is, their high speed manufacturing does let some lemons slip. Re: the ratchet barrels that they let out. Third, the only Savages I have is two of this style, but I became so sick of their complexity that they have been laying in pieces for years with match grade barrels waiting, and I'm actually afraid to bother the gunsmiths around here with a firing pin change on one. Don't worry I will get up the courage to tackle it or have it tackled, I'm getting the urge back. Just so you know, I was a degreed manufacturing engineer, have tinkered with guns most likely longer than you have lived, and I converted both of these RH actions to Left Bolt and they are both done except some stupid annoying details like the firing pin. In my life I've also converted a Springfield and a Remington. Rebuild a 1903 Springfield or Mauser and see why I just got sick of these two.
    1. kapman's Avatar
      kapman -
      Extreme cold can also be a factor. Have experienced it wolf hunting at-40. Cure is no lube on bolt
    1. Robinhood's Avatar
      Robinhood -
      Quote Originally Posted by kapman View Post
      Extreme cold can also be a factor. Have experienced it wolf hunting at-40. Cure is no lube on bolt
      True Kapman, and a good point. I mentioned poor choice of lubricants with the intent of covering the dampening effect of dried out lube but was not clear on the cold weather impact. Most of you northerners and Kanuks are already familiar with freezing weather and its effects on everything not just rifles. Duely noted.
    1. Bigfoot's Avatar
      Bigfoot -
      I use kroil, to test it I placed a bottle cap full of it in my freezer for 3 days at minus 11 degrees, there was no apparent thickening or wax formation, hunting at minus 20 with no problems with 6.8 AR platform. good stuff.
    1. SFLEFTY's Avatar
      SFLEFTY -
      Quote Originally Posted by kapman View Post
      Extreme cold can also be a factor. Have experienced it wolf hunting at-40. Cure is no lube on bolt
      Is that Fahrenheit?
    1. dfrosch's Avatar
      dfrosch -
      Quote Originally Posted by SFLEFTY View Post
      Is that Fahrenheit?
      Curious thing... -40°F is the same as -40°C.
    1. blvedere's Avatar
      blvedere -
      I have had light strike problems and finally found "my" problem was when I installed the bolt head pin, I did not get it centered and the firing pin was riding on the ID of the bolt head pin.
    1. Robinhood's Avatar
      Robinhood -
      Quote Originally Posted by blvedere View Post
      I have had light strike problems and finally found "my" problem was when I installed the bolt head pin, I did not get it centered and the firing pin was riding on the ID of the bolt head pin.
      I wondered if there was anyone who has had that problem. I have never seen that happen even after the hundreds of times tearing them down and back together. When I first started messing with them I thought It would be easy but the wavy washer has always prohibited it from moving.
      I
    1. blvedere's Avatar
      blvedere -
      I perhaps stated my problem incorrectly. When I inserted the bolt pin I did not get the C/L of the bolt pin hole, that the firing pin went through, lined up with the C/L of the firing pin, allowing the firing pin to rub on the bolt pin. Don't know if that explains it any better. LOL