They changed the bolt lock safety over in '75 or 76. The change allowed the bolt to be operated with the safety engaged (on SAFE) to unload the chamber &
magazine if you wished to.

Prior to that, the design only allowed and expected you to place the safety on FIRE or F (with a round in the chamber to be unloaded!), lift and open the bolt and pull it to the rear,,unloading the chamber.
Then before sliding the bolt foreward again, re-engage the safety to the Safe or S position.
Then go ahead and slide the bolt forward and back to empty the rest of the magazine,,or just remove the entire box magazine from the rifle by detaching with it's catch.

You can see where the first part of the operation begged for a accidental or negligent discharge.
There never was a out and out Recall on the old style bolt lock safety on the 788. There was a factory notice about it's proper operation and the cut off time in production ect put out.
That was tagged along with the Model 700 bolt lock recalls in '02 or '03 a couple times as an additional note.

The .223 cal came out about the same time in 1975. I don't know if they all have the later bolt lock safety mechanism.

Nice little rifles they are. Accurate for sure.
A local shop just had a NOS .223 version w/box on the rack and priced at $499 and it went in a hurry.

The hard soldered on bolt handle has always been an issue with the 788. Seems they used an induction type process and not a very good one. Or the solder & flux wasn't right or something.
Some of them just have a poor bond betw bolt handle and bolt body.
Done right you can beat on a hard soldered joint all day and only end up bending the steel parts involved.
The induction process was used so as to keep any excess heat away from the rear locking lugs on the bolt body. Maybe a couple extra amps were needed on some!
Induction can heat the part and small area needed to the right temp in a couple of seconds and then cool right back down.
It's used quite a bit on SxS shotgun bbl to braze the breech ends together now instead of furnace brazing them

The 30-30 and 44mag versions bring a lot of attention and $$ now.

Grab any extra magazines you find as they are becoming harder to find. The 222 and the 223 magazines are interchangeable.