Re: Remington 700
KT88
Trigger pull weight has a relationship with the amount of sear/trigger engagement.
If memory serves me correctly you indicated that your trigger pull has become erratic, which indicates to me the trigger pull has enough variation that you can feel the difference from rep to rep... but also the trigger pull becoming so hard that you believe the safety is on when you pull the trigger.
I have heard of this happening on other X Mark Pro fire control(s) (hence a trend I have observed) - from a Sniper I shoot/work with with training from time to time. He reported the same thing happening to him at an event we were both at, with his duty rifle last year. What I am forced to wonder is the amount of visible wear that can/might be observed on the sear?
For starters, pull the bolt from the action and look at the top of the sear if you would - do you detect any wear on the sear from the cocking piece as it rides down the length of the sear, as the sear rotates downward to release the striker?? Also look for indicators that the cocking piece is rubbing, or getting caught on the edge of the fire control housing - I am wondering IF you ARE pulling the trigger to the full extent of its travel, but the sear is not releasing the striker?? Next time this happens, with the trigger pulled, jar the rifle with your palm of your other hand & see if this releases the sear/striker?? Frankly, I would not think you should see much, if ANY visible wear on the sear, with only 250 rounds down the tube, but check it out and report what you observe - If you want?
As to another potential explanation involving an erratic trigger pull:
I am wondering if this might possibly be an indication that the return spring has taken some "set", thereby creating a situation where the trigger is not returning to a consistent sear/trigger engagement condition? In other words, one rep lets say you get engagement of 15/1000", another rep - say 25/1000" of sear/trigger engagement... assuming the system is clean as you have already indicated.
As far as dry fire drills, they are a good thing to practice, so I am not pointing out any blame on your part IF you have been performing such drills, as a matter of fact, I would encourage you to do so... just use a snap cap in the chamber while doing so.
Aug ><>