Mag sear problem, I’m pretty sure….where are the gurus?

[GrumpySmurf429]

So, I’m revamping the teal splash mag in my profile pic. I switched the rail to a benchmark rail. The first thing that wouldn’t fit was the sight rail because the benchmark one comes so high up the sides of the body, no big deal I decided to ditch the splash. The sear pin was too fat to fit into the slot in the rail, so I sanded the ends down until it fit, next the pin to the trigger seemed way to short, it wouldn’t even fire. I adjuster the trigger pin out to where it seems it would normally be. Same thing, won’t fire, sear pin is sticking in the frame and won’t protrude out to the trigger unless I disassemble the bottom half. Any ideas? It does not appear to be a setup for an RT sear, no hole in rail, way too large diameter to accept the skinny side of the pin. Any theories here? Even if they involve aliens….im listening.

[GrumpySmurf429]

Really? Nobody? I’ve gotten it as fas as firing once but won’t recock by messing with the sear length.

[F1FX]

A few questions for you. Any pics of trigger rod when aired up? Was it working before you changed rails? Is sear pin all the way down in the slot in the rail? Without frame attached does sear moves freely or is it binding/rubbing on rail?

[GrumpySmurf429]

It worked flawlessly before I swapped rails. Trigger rod stays inside the frame when aired up regardless of adjustment. It has only popped out 1 time, it fired, retreated back inside, and nothing ever again. The rail is benchmark if it helps.

[GrumpySmurf429]

Sear moves free as something blowing in the wind.

[Alexndl]

Pictures for the sear, rail and frame?

[GrumpySmurf429]

It won’t show you anything

[GrumpySmurf429]

I’ve since taken the aka sidewinder I put on at the same time off thinking it maybe wasn’t outputting enough pressure. I swapped on a gas thru grip. Same thing. I have to crank the back of the marker so high it leaks from multiple places, the sear pops out, it has like a 50lb trigger pull, fires once, sear stays retracted, no recook.

[GrumpySmurf429]

Here’s a basic assembled pic

[nak81783]

I know you said the sides of the rail reach further up the sides of the body, but that rail looks thick to me. Does it measure the same thickness from the face that contacts the trigger frame to the radius that contacts the body as the AGD rail?

I don't know anything about Benchmark rails. Are they meant to be used only with Benchmark bodies and trigger frames?

If you put the AGD rail back on, does everything go back to shooting properly, assuming you change back any other adjustments you made (e.g., trigger rod)? I realize you want to use the Benchmark rail; I'm just asking for troubleshooting purposes.

[GrumpySmurf429]

Not sure what you’re asking measurement wise. It’s definitely chunkier. Wider yes, taller yes.

[Melrosejedi]

Makes me beg the question, is this rail ok with level 7 or made for a RT, or another version. The other mags have different sears then the classic. Sounds like the on/off pin cannot push your trigger farher due to the distance to the trigger. I would look into the rail applications,and if it is then maybe a longer rod on the sear.

[GrumpySmurf429]

This I have no idea about, I saw one online, liked the way it looked and hunted one down. However if it was built for the RT, wouldn’t it have a hole for the rt sear and holes for the rails?

[Melrosejedi]

I dont know, i have only messed with a classic setup. I have set up several hyper frames and the issue is always on/off pin length to operate the sear correctly. Sounds like you have exceeded the operating length of the trigger push rod.

[FredMnkyDad10]

I would say switch everything back. If it works again then you know it's the rail.

I had the same rail. Cant remember why I sold it, but I think I was having issues with it too. If you like that look, look for Taso rails or place WTB post. They have different milling on the side including pills and pill/channel.

I been tinkering this weekend on a few classic mag setups. And just came across the sear pill issue mentioned above.

Started with the pill not fitting in the rail. So picked up another pill, and another. 4 different pills and rails. Only 1 pill fit in the 1 rail and barely. If you did not pay attention youd think they dropped all the way down, they did not.

Not sure you can tell in the picture. But the 4 pills above the edges are more flat/straight cuts. I pulled the lower two from other builds and you can see they are more round/beveled.

[GrumpySmurf429]

This is the initial problem I had. I used a dremel to round off the ends like the single one you have posted, that’s how I got it to fit.

[FredMnkyDad10]

Couple samples of Taso rails.

[GrumpySmurf429]

Thank you to all for the input I solved it. I need to round over one of the ends of the sear pin just a tiny bit more. It was sitting like a mm off the bottom of the slot on one side making it sit crooked and bind up. Shoots like new again.

[FredMnkyDad10]

Damn I wonder if that was the issue with the benchmark I had and I never saw it. Oh well have to keep that in mind for the next time. And got grind some of these down.