A pierced primer occurs when the primer fails during firing, allowing high-pressure gas to escape rearward into the firearm. This gas can potentially damage components such as the firing pin, breech face, action, and trigger.
An overpressure event is similar, except the primer may remain intact while excessive chamber pressure still causes damage to firearm components. Common signs of overpressure can include ejector marks on brass, flattened primers, or difficult bolt lift.
The severity of pierced primer or overpressure events can vary significantly. In some cases, no damage occurs, while severe events may cause substantial damage to the firearm and internal components. Some firearm actions include gas venting features that may reduce the severity of the damage.
What Should I Do?
- Always inspect fired brass for signs of overpressure or pierced primers
- Have the firearm inspected by a qualified gunsmith before continued use after an overpressure event
- Stop using the trigger immediately if you notice:
- A sudden change in pull weight
- Inconsistent trigger behavior
- Reduced ability to hold the firing pin when closing the bolt
A TriggerTech trigger’s pull weight may change slightly over time as components wear in, but changes should remain gradual and should not exceed approximately 6 oz or 15% of the set pull weight, whichever is less.
Do not attempt to compensate for abnormal trigger behavior by simply increasing pull weight.
Always perform proper safety checks before use and follow all applicable firearm safety rules.
If you suspect your TriggerTech product may have been affected by a pierced primer or overpressure event, please contact TriggerTech Support:
- support@triggertech.com
- 1-888-795-1485