I have a 75 mod Sako which has a problem with the trigger adjustment screw.

Over time, and exposure to extreme conditions I noticed that the trigger became heavier.

I had adjusted it to the lightest setting it could take without going off when you slam the bolt. Now the hammer will drop if you're not careful, and the adjustment screw does very little to change the trigger pull.

It's not at a level I would call dangerous, because you have to give it a fair old whack to set it off, and the trigger isn't too heavy but I would like to rectify the situation.
So far I have limited my tinkering to taking the trigger out and brushing thouroughly with a toothbrush, but ther wasn't really much gunk in there to start with.
In the past I had sprayed WD40 into it, but shook it out before reinstaling, and it hasn't really seen a whole lot of dust to clog it up.

A friend suggested I just pull it all apart and put it back together again, which has work for other mysterious problems in the past.

Does anyone here have any other suggestions?

Express ,
I had some problems with the trigger on my L579 and messed around for 2 years before I worked out that the lubricant inside it had gone tacky and was causing inconsistency . I was getting occassional hangfires .
Have had experience with some products like WD 40 becoming tacky with age too .
Think they're designed to be that way .
In the end I flushed the whole thing thoroughly with petrol , re- lubricated with a light oil specifically designed for use in firearms and solved the problem .
Easy to do and definitely worth a try as the gradual increase in your trigger pressure sounds a bit sus .

Shoulda though of that myself...Thanks mate.

Express ,
BTW have you done the dive / hunt trip that we discussed yet ?

Bushchook, I've sent you a PM about the trip, and have the trigger in petrol right now. I was thinking it would be nice to be able to keep it oil free and lube up with graphite for this hunt to save it from getting all clogged up with bulldust, but then I suppose it would rust?

I'll try a light coating of WD40 blow out the excess with the compressor.

Express ,
Why not try something like G 96 complete gun treatment if you can get it there ? Comes in a spray can and doesn't go tacky in my experience .