a few observations on my S-12

[tretpflyr 2]

Earlier, you guys helped me out with my bolt jamming problem. Want you all to know that I got it fixed. A friend advised me to coat the bolt surfaces and reciever serfaces with valve lapping compound then work the bolt several hundred times. IT WORKED!! I cleaned it all up put it together and it runs MUCH better now. I ran 4 boxes of low brass on the #2 setting but the high brass ran far better and perfect on the #1 setting. Isn't that what we are supposed to do? ... run the mags on #1?

 

One area of possible improvement I think, could be the hammer. It seems to make the largest contribution to drag on the bolt and I can't help but think that taking 1/38th off the surface of that hammer and then smoothing it out would help it run even better. Any of you done this?

 

On aftermarket parts: I found the "gun fixer" gas adjuster to be about worthless. The stocker works better, far better, in my gun. I did put in a twister puck but I see no real difference thus far.

 

Now I am psyched to do the mod. Parts are in hand and I will start it next weekend. Any advice/suggestions greatly appreciated.

[vitamink 90]

I'm glad to hear you got your stuff running. Polishing the internals is an excellent way to lower your friction coefficient and make sure everything slides like buttah, i wouldn't screw with the hammer though. You may find that it won't "cock" anymore, or worse you may find that you now have a full auto/multi round burst s12 and the guy next to you at the range is ATF agent. The gunfixer gas plug is an excellent piece, but you're not using it to it's potential. where the gunfixer plug shines, is if you're going to the range with several different ammo types birdshot/buck/slugs and you need to switch on the fly and not mess around with pressing a button and using a tool to unscrew the knob. It also makes it easy to clean when all you have to do is unscrew. The gunfixer is more helpful in overgassed guns than undergassed, but i'll bet once you get her broken in you'll begin to appreciate the ease of use.

[Paulyski 2,227]

Earlier, you guys helped me out with my bolt jamming problem. Want you all to know that I got it fixed. A friend advised me to coat the bolt surfaces and reciever serfaces with valve lapping compound then work the bolt several hundred times. IT WORKED!! I cleaned it all up put it together and it runs MUCH better now. I ran 4 boxes of low brass on the #2 setting but the high brass ran far better and perfect on the #1 setting. Isn't that what we are supposed to do? ... run the mags on #1?

 

One area of possible improvement I think, could be the hammer. It seems to make the largest contribution to drag on the bolt and I can't help but think that taking 1/38th off the surface of that hammer and then smoothing it out would help it run even better. Any of you done this?

 

On aftermarket parts: I found the "gun fixer" gas adjuster to be about worthless. The stocker works better, far better, in my gun. I did put in a twister puck but I see no real difference thus far.

 

Now I am psyched to do the mod. Parts are in hand and I will start it next weekend. Any advice/suggestions greatly appreciated.

If you do a trigger polish & want to smooth it, only remove a touch of steel JUST where the lower bump is (underneath where the firing pin is hit)

Just a touch. If you do it to much, you not only worry about the warning above, but slamfiring. That wouldn't be cool with 12 gauge

[3ac6ucb 24]

Yep, polishing the hammer will make a big difference. If you compare a Tromix-modded Tapco G2 hammer versus a stock one, you can see how the top surface has been reprofiled. IIRC, Tromix also relieves the side of the hammer pivot to make room for the factory BHO.

 

VitaminK has the right idea with the gunfixer plug - it will let you run a greater variety of shells than the stock gas plug will. Plus the knurling makes it easy to adjust without tools.

 

I'm not sure what the rule of thumb is for being overgassed.... say, maybe if your shells are ejecting farther than X feet away? My 4-port 19" S-12 has polished internals and a stock length gas system, and it kicks birdshot about 6 to 10 feet on Gunfixer setting 2. For me at least, setting 3 serves as an "adverse" setting if the gun gets badly fouled. It's totally not needed when clean. Setting 1- is enough to run high brass reliably for me at the range, but 1+ doesn't launch shells into orbit, so for HD I keep it on 1+ for that extra margin of reliability.