Sorry Pete.
The triggers are adjustable, by a very good gunsmith.
Here is what i would do and see it this helps. I do this to my shotguns to keep the trigger constant.
I do not think your trigger is a drop out, so you will need to remove the stock. You could send the hook and sear to be titanium coated. (be careful on this one, it reduced my trigger pull to less than 1 pound on my P gun.) When putting the stock back on, tighten the lug bolt until it is snug then turn the wrench 1/4 more turn for a consistent snugness. (recommended by major gun makers)
Clean the trigger, i use G96 spray cleaner and lube. Wipe off excess (use q tips in tight spots) and let it sit for about 10 min to drain any excess and wipe again.
Look at your trigger sear and hook. Now use a magnifying glass and look at your hook and see for any metal unevenness (you will find some). Depending on what you find, this is where a good gunsmith with a hone will reduce these grab areas. I have my P gun set up for 3 1/2 lb for the first shot and 3 3/4 for the second shot.
During drying time take some good wax and polish your stock. Wax that does not clean i will add.
Now What i use, is a release trigger grease, take a q tip and lubricate the hook and sear. Try this, you will see immediately that the trigger pull is lighten and more consistent. Do you have a trigger pull scale? I have one with me all the time when traveling with my shotguns. You need to have one to check to see that your trigger pulls is staying the same or if work need to be be done to the trigger..
If you have a difficult time finding a good grease go to a bicycle shop and look for a very good synthetic chain grease, i use tri-flow grease when putting the action and forearm on.
You will need to check the inertia block for hang up also and lubricate it also. You also have a selector button that need to be cleaned and lubricated.
Tri-flow makes a oil and grease that some of the top gunsmith recommend. I use a few drops of tri-flow oil for the ejectors.
When i work on another shooters trigger i do the following:
Check tripper pull poundage. then here we go.
1. Spray with carb cleaner.
2. Spray with G96
3. Wipe and dry
4. Q tip time
5. Q tip grease apply time.
6. Check trigger pull poundage.
7. put gun back together.
Surprising what a good trigger cleaning and lub job will do.
I carry my honing stones along and they have only been use by 2 other persons than my self.