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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