Does anyone have issues with dropping the weight on Triggertech with the Impact action?
On my Impact Precision I cannot safely go below about 10-12oz with a Triggertech Diamond. 10oz is completely drop-safe, but it's not until you get to about 12oz that it's safe even if you run the bolt as fast and hard as you can (more on why closing the action is harder for triggers in an Impact than the drop test later).
The reason, almost certainly, is because the action is 50/50 cock on open/cock on close and it has a heavy firing pin spring. This means that when you go to close the bolt there's a lot more pressure on the sear of the trigger since it's being used to finish cocking the firing pin, especially considering the stout firing pin spring. More pressure against the sear means it's harder to get a light trigger pull that remains drop safe, and cocking on close makes it harder to get a light trigger pull that's safe when slamming the action home hard and fast.
Here's what the Triggertech website has to say about that sort of thing:
All pull weights and measurements are approximate. ***Pull weights of TriggerTech Triggers are directly impacted by firing pin spring weight. Overweight firing pin springs may cause pulls weights to vary above the advertised range***
The Impact has an overweight firing pin spring, if memory serves me correctly it is 26 pounds compared to the 20-22 pound springs you find in most Remington 700 short actions. It's also cocking on close, which will always put more pressure on the sear than if you aren't cocking it as you close the action. Based on that info and what TT says, it makes sense that a TT Diamond can't get down to the 4oz advertised and is instead closer to a 3/4-1lb trigger on the Impact action.
For me it doesn't make much difference. I used to like my trigger at 8oz when I had my Nucleus, but I caught myself falling into the habit of slapping the trigger. I've got my Diamond set to 1lb now and it's helped me break that habit since it's just heavy enough to be seriously noticeable when I do stupid stuff like that. I make up for the "heavy" trigger (by PRS standards) by enjoying the super light bolt lift of the Impact. It's also a lot safer now if I am taking others to the range with me, since it now only takes them a couple shots of dry fire to get used to the trigger instead of multiple minutes before they're not accidentally setting it off.
