Kinda guessing that yours has a military two stage trigger, and the other ones that you saw had a commercial trigger. Post #2 suggested taking the rifle out of the stock and you would see it happen as you cycle the bolt - your picture in Post # 3 is showing that you have taken the bolt out of the rifle. Take the rifle out of the stock and watch the trigger as you cycle the bolt - am sure that will make it clear to you what is going on.
Also, perhaps a detail - trigger should not move if you have simply closed the bolt and then opened it - unit stayed "cocked" all the time. Quite probably it will move if you have closed the bolt, dry fired it, and are re-cocking it as you open the bolt. Assuming that you have a standard military sear and trigger arrangement. Commercial triggers work differently.


In your picture of the bolt - can see the underside of the cocking piece - those areas separated by the "V"'s - front edge is to be held back by sear until trigger is pulled - then cocking piece slams forward to fire the rifle - trigger sear ends up between those "V"'s - will be pressed down as the bolt is opened and pulled back. Just took a quick look at a 1909 Argentine on the work bench - its "V"'s are more central, perhaps back a bit more - any evidence whether the cocking piece is original to your rifle? Often has the last two digits of the rifle's serial number on the very rear end of it - but many are not marked at all. My best guess, without seeing your trigger and sear, which require removing rifle's action from the stock.
"safety is stuck in the fire position" - that is likely because that safety and that cocking piece have never been fitted together - that particular issue has nothing to do with the rifle - is between the safety lever and the cocking piece. However, your description about the trigger also raises questions about the cocking piece, so may be truly is your problem. Mixing and matching - what could go wrong? Mauser 98's were made in dozens (?) of countries and factories, for 50 + years - and subtle variances between them - most definitely not always a "drop-in" solution, although if, for example, you have Argentine marked parts, they will be very nearly all "drop in". No one said that a Yugo safety was going to work in an FN bolt with an Argentine cocking piece when installed in a Czech receiver, though.
"safety is stuck in the fire position" - that is likely because that safety and that cocking piece have never been fitted together - that particular issue has nothing to do with the rifle - is between the safety lever and the cocking piece. However, your description about the trigger also raises questions about the cocking piece, so may be truly is your problem. Mixing and matching - what could go wrong? Mauser 98's were made in dozens (?) of countries and factories, for 50 + years - and subtle variances between them - most definitely not always a "drop-in" solution, although if, for example, you have Argentine marked parts, they will be very nearly all "drop in". No one said that a Yugo safety was going to work in an FN bolt with an Argentine cocking piece when installed in a Czech receiver, though.
If you want to play with this stuff, eventually, my suggestion would be to get a set of decent gunsmithing screwdrivers first. I buy stuff and just amazing to me how many people appear to have no clue that owning a Canadian Tire one-size-fits-all screw driver does NOT qualify them to work on guns or scope mounts. Should be able to remove and re-install a slotted screw with no sign whatever that it had been touched - screw driver has to fit exactly - to be ground with parallel sides and full width - for many of us a single screw is a lot more expensive to find "one of" to replace, than is making a properly fitting driver in the first place. I happen to use a Wheeler Engineering kit, but have dozens of extra bits ground to fit particular slotted screws. Next, I don't do U-tube much - I am old-school and prefer books - so for Mausers, get a copy of Jerry Kuhnhausen "The Mauser M91 through M98 Bolt Actions - A Shop Manual". There is so much stuff that has been "forgotten", that a WWI soldier could do without tools, in the rain, sitting in a muddy ditch, in the dark.
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So does the lug thingy on the cocking piece push down on the sear when you rotate the bolt causing the trigger to move?
The trigger is also loose when it gets pushed back when I #### it; so I can easily stop it from moving when I'm cocking the gun if that adds any useful information.



























