Just sharing something I've found to fix internal lock plugs that happen to not fit flush with the exterior of the receiver and/or sit lose (either drive me nuts). I'm finicky enough with just a hint of OCD that those plugs had better sit flush and snug or I'll lose sleep over it (figuratively). If I'm going to spend $40-ish for each of those plugs then they'd better fit flush and not move.
First off, I've now done 5 of my own (two 686's, a 66, a 69, and a 29), and 3 of my friend's revolvers (two 66's and a 586). I've used TK Custom and Original Precision brand plugs and both brands seem to have variations in height with no rhyme or reason to which finish or kind of metal is being used (or maybe it is the revolvers?)... ultimately both work equally well. Only one of the 8 have fit flush with no movement. The other 7 have all received this "trick" to bring them flush with the exterior and to eliminate any movement.
I put a slight bend the very tips (2mm worth?) of the "Y" retainer to force the plug upwards/outwards towards the exterior of the receiver. I'll hold the "Y" with a set of small regular pliers from the rear leaving both of the front tips exposed (that part that slides through the grooves in the plug) and with a needle nose put a slight bend in the tips. I'll install the spring on the leg and then slide the retainer in to the slot in the receiver with the bent tips point towards the hole. I slide the plug in to the hole from the outside, apply pressure to the "Y" retainer to get it to move rearward and out of the way, align the plug grooves as needed, and then slide the Y retainer forward. Due to the bent front tips I'll sometimes I need to apply a decent amount of pressure forward so the Y will slide in to the grooves of the plug. If the plug extends out of the receiver too far I use a nylon punch larger than the hole, and a light tap from an appropriate hammer to get it flush. Easy stuff.
On one revolver, a Model 69, I installed the plug without putting a bend in the Y retainer. Instead of uninstalling and putting the bend in the two Y tips I grabbed my Wheeler hammer and punch set and gave the plug a decent tap or two from the inside (while it was still installed). That seemed to put a bend in the Y retainer (I'm guessing at or above the neck of the Y) enough to push it flush and hold it tight. Thus far it hasn't moved with maybe 100 or so rounds of .44 Specials and maybe 10 rounds of .44 Magnum. I'll count it as a "win". I might go this route from this point onward since it actually installs easier due to not having to fight the bent Y retainer in to the slot. I just bought a new Model 10 with the lock so we'll see...
So there ya have it... Cheers.
First off, I've now done 5 of my own (two 686's, a 66, a 69, and a 29), and 3 of my friend's revolvers (two 66's and a 586). I've used TK Custom and Original Precision brand plugs and both brands seem to have variations in height with no rhyme or reason to which finish or kind of metal is being used (or maybe it is the revolvers?)... ultimately both work equally well. Only one of the 8 have fit flush with no movement. The other 7 have all received this "trick" to bring them flush with the exterior and to eliminate any movement.
I put a slight bend the very tips (2mm worth?) of the "Y" retainer to force the plug upwards/outwards towards the exterior of the receiver. I'll hold the "Y" with a set of small regular pliers from the rear leaving both of the front tips exposed (that part that slides through the grooves in the plug) and with a needle nose put a slight bend in the tips. I'll install the spring on the leg and then slide the retainer in to the slot in the receiver with the bent tips point towards the hole. I slide the plug in to the hole from the outside, apply pressure to the "Y" retainer to get it to move rearward and out of the way, align the plug grooves as needed, and then slide the Y retainer forward. Due to the bent front tips I'll sometimes I need to apply a decent amount of pressure forward so the Y will slide in to the grooves of the plug. If the plug extends out of the receiver too far I use a nylon punch larger than the hole, and a light tap from an appropriate hammer to get it flush. Easy stuff.
On one revolver, a Model 69, I installed the plug without putting a bend in the Y retainer. Instead of uninstalling and putting the bend in the two Y tips I grabbed my Wheeler hammer and punch set and gave the plug a decent tap or two from the inside (while it was still installed). That seemed to put a bend in the Y retainer (I'm guessing at or above the neck of the Y) enough to push it flush and hold it tight. Thus far it hasn't moved with maybe 100 or so rounds of .44 Specials and maybe 10 rounds of .44 Magnum. I'll count it as a "win". I might go this route from this point onward since it actually installs easier due to not having to fight the bent Y retainer in to the slot. I just bought a new Model 10 with the lock so we'll see...
So there ya have it... Cheers.
). This plug was a challenge to get turned in the hole so the grooves lined up with the Y retainer (I tried to get all of the plugs aligned as close as I could but if they weren't close enough I'd rotate them in the hole using a toothpick). Cheers. 
