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Posted: 2/22/2008 3:50:29 PM EDT
| What would cause light primer strikes?? I was teaching a rifle class yesterday and one of the students was using a DPMS 16 inch rifle. Throughout the course, he experienced several fail to fire due to light primer strikes. Is it the weapon or ammo? I'm leaning toward ammo, but wanted to check. He was using Remington 55gr .223. |
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The two concerns will be the bolt failing to lock up completely, and the FP not having the correct protrusion once the bolt has locked up. Short of that, then you get into the tension of the hammer spring, and if it was installed correctly (read coil orientation and spring legs resting on top of the trigger pin, and not on the bottom shelf of the receiver). FP protrusion range is .032 to .037 with its back end seated flush against the back of the bolt. Spring install is coils winding rear upwards/ top forwards, and again spring legs on top of the hammer pin. As for bolt failing to lock up, bolt/chamber first head spaced checked, then the upper checked for binding, such as a key too wide for the upper track, recoil spring end of bur, or just hammer wedging or lake of lube/ a clean chamber that may be leading to short stroking problems. Also, a new mag that has not been cleaned, or burs on the bottom of it's feed lips could cause the fail to lock up as well. |
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I would check the firing pin. I would pull it out and check it against a known good one. Heck if you dont loose track of the pins you can even swap them to see if the problem carries over/fixes it self. You will not cause any problems swaping pins. If that doesnt fix it. Try different ammo, if your positive its not the ammo, then check/replace the hammer spring. Other than that the only other thing I know it could be is a mis machined bolt. Not too sure but I wouldnt put it past any manufacturer to have bad parts come out. |
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