Smart Mag has a long, mushy trigger pull

[ghost flanker]

This is a friend's Smart Mag (has the big tumor growing out the side of the valve). It has no detectable leaks and shoots fine, but the trigger pull is utter crap. Long, mushy, not snappy at all like an AGD classic mag. Trigger rod is properly adjusted, and we swapped out the sear and the on/off from my classic mag into his SP mag, yielding no difference in the trigger feel. I'm stumped.

Do all Smart Mags have a trigger pull that feels like this? Caused by a difference in operating pressure, maybe? I've never owned one, so school me.

[Nobody]

Look at the bolt, bolt spring and check the valve for any detritus in the air flow to the on/off.

Conversely, try your valve in the gun to see if and or where the problem can be. Process of elimination

[going_home]

Is it a benchmark frame ?

[athomas]

I was going to ask the same question. What type of trigger frame is on it? That is usually the cause of a mushy trigger. Benchmark trigger frames are notorious for being sloppy. You can fix that by shimming the trigger so that there is less side to side action.

Another place that might cause it to be less snappy is if the powertube spacer is too short.

[ghost flanker]

The bolt spring is in good condition, of sufficient length, and not worn out. The bolt appears to be in good condition, as well.

His mag does have a single-trigger Benchmark frame, but I don't think that is the culprit. I have a single-trigger Benchmark on one of my own mags, and I'm more than accustomed to the side-to-side trigger slop that's inherent in the design. But it's still quite crisp/snappy and short. That is not what this is. When I say long trigger pull, I mean looooooong. Like 1/4" travel of the trigger before this mag will finally fire. I doubt an AGD cf frame's trigger would afford enough travel to even fire this gun...that Benchy might be on there for a reason. And it's a fairly light and soft trigger pull, too. Maybe 3 or 4 pounds. Very, very un-mag. Feels like a limp handshake. It's the weirdest thing.

I'll do a process of elimination troubleshooting party next time I see him. He lives pretty far from me so it might be a while til I get around to it, though. I mostly just wanted to confirm with any Smartmag owners here whether or not this is normal.

[Laku]

Just side observation, but your friend has "magic box mag" not smart mag (unless it says so on the valve side).

I have smart mag and as far as I can tell the trigger feels the same as on any other classic valve.

What kind of tank regulator is your friend using?

[ghost flanker]

My mistake. Yes, it is a Magic Box Mag. I'm pretty sure it says "smart mag" on the valve, too, but now I'm doubting myself. The gun's reg is stock. I don't know what tank regulator he uses. That's a good point. I'll ask. Do magic box mags function on lower pressure than standard classic valves?

[Nobody]

My mistake. Yes, it is a Magic Box Mag. I'm pretty sure it says "smart mag" on the valve, too, but now I'm doubting myself. The gun's reg is stock. I don't know what tank regulator he uses. That's a good point. I'll ask. Do magic box mags function on lower pressure than standard classic valves?

What is was supposed to do and what it actually did are 2 very distinct and different things.

[ghost flanker]

What is was supposed to do and what it actually did are 2 very distinct and different things.

Huh??? Sorry, I'm really not sure what you meant there, but your post did remind me of this: https://m.youtube.com/watch?v=L6h-zFdWZdc

[Laku]

All the magic box and smart mag valve mod did was increase the dump chamber volume. So theoretically I guess the chamber operates at slightly lower pressure, not sure how that works out in reality though. The 8 hole mod didn't actually help anything since the valve halves at that time were already indexed to match. Then there was all the hype about longer shot range and stuff, that was pure marketing bs.

[Nobody]

Huh??? Sorry, I'm really not sure what you meant there, but your post did remind me of this: https://m.youtube.com/watch?v=L6h-zFdWZdc

The magic box was supposed to be a wonder for all mags, per SP marketing, to lower pressure, make a softer shot. It only increased the chamber volume with negligible pressure results (remember, it was taking air for the regulaor side).

What it did was, allow co2 users a little extra area to have liquid in to get a hot ahot (a la thumbing the cocking rod on a cocker) and to take money out of the pocket of people who chase mods for modding sake.

Its funny when you look through the years at SP's blatant lies, fabrication and obfuscation on physics, the truth, and plain common sense. "Spiral porting will cause the ball to spin, giving better accuracy on a shot". That was a true statement made by SP on their spiral ported barrels like the All American barrels.

[ghost flanker]

Well, if you increase the volume of air that pushes paintballs through a barrel, then the velocity will increase. Right? So, in order to bring the velocity back to where it was before we increased the volume, we must lower the pressure of the air to compensate.

[Nobody]

The volume is increased but the pressure is still the same. You are gaining volume but not loosing pressure or at least such a slight change that the difference is negligible to the operation of the gun. And at the time that this fad was new, you only had 3k tanks, so the efficiency only went down. This was in the time that "low pressure" was a fad that not many people understood in the relationship of the operation of the gun.

Again, the 2 things it did well was take money out of your pocket and ruin your valve.

[athomas]

Theoretically, the larger dump chamber would reduce the pressure required. That would work if all the air dumped at the instant the bolt was released. In a mag with the bolt spring acting like a restrictor, it didn't work that way. The larger volume just meant that there was more air leaving the valve after the ball had exited the barrel resulting in less efficiency. That is why the most recent mods actually reduce the chamber size, thus increasing the chamber pressure and causing a shorter high pressure burst which wastes less air after the ball has exited the barrel.

When you indicate the trigger pull length is long, what is the actual distance that the trigger rod moves? Is the sear pin pressed firmly down into the rail?

[ghost flanker]

athomas,

The actual distance the trigger rod must move before the gun fires is about 3/16" to 1/4". There is a 1/16" space between the trigger and trigger rod. As far as I could tell, the sear pin was seated just fine. I swapped out the sear with one known to be good just to make sure...same result. I neglected to inspect his rail more closely to see if there was any sort of defect, but I didn't notice anything unusual there when I took his gun apart. I would liked to have been more thorough, but we were at a paintball field, so time was kind of limited.

Regarding the Magic Box Mag... so its operating pressure, in reality, is roughly equal to that of an AGD classic valve?

[Nobody]

AFAIK, yes the operating pressure is the same or slightly lower. You aren't changing the reg pressures, just the volume of the dump chamber, but i think there is a mathematical relationship between preasure & volume, but i dont know it.

[athomas]

The pressure impulse from a magic box that actually pushes behind the ball is about the same as with a regular valve, but the trailing air pressure lasts longer because of the increased volume. Given that the pressure impulse is about the same, the operating pressure to provide the amount of force to develop the required velocity is also about the same. The pressure with a magic box is a tiny bit lower than the standard mag, but not enough to really notice or make a difference given that everything else is the same.

Nobody: The pressure volume relationship is P1V1nRT = P2V2nRT. The values of nRT (number of moles, gas constant, temperature) are constant given that you are using the same type of gas at the same temperature. Therefore P1V1 = P2V2. However, this equation only represents the starting pressure in the chamber under ideal conditions if all the air could be delivered instantaneaously and not the pressure applied behind the ball because of the bolt stem restriction in the air delivery to the ball.

[athomas]

When you have the valve removed from the body, look at how the trigger rod moves to allow the sear to move from the forward reset position to a point where the sear just clears the body? That movement will give you an idea what you are dealing with from a visual standpoint.

[Cyco-Dude]

His mag does have a single-trigger Benchmark frame...

there you go. the trigger rod is closer to the pivot point on benchmark frames compared to an agd frame, which results in an easier, but longer-travel trigger pull as you have more leverage. it's opposite on the agd frames; shorter but stiffer trigger pull because the rod is farther away from the trigger's pivot point.

no issues here.

[ghost flanker]

But I own a Benchmark frame and am extremely familiar with how they normally feel. My classic mag with a Benchmark feels NOTHING like his magic box mag: soft and long pull vs. stiff and still pretty short pull. I hear what you're saying about the pivot point, and that's a good point (badum tsst), but it's still a very short pull on my benchy'd gun. I don't have to pull the trigger a full quarter inch on my gun before it fires. With his gun, you do. I'll definitely try an AGD frame on his gun next time I see him, though.

[ghost flanker]

athomas,

I'll be sure to do that next time I see him. Maybe this Sunday. Thanks, buddy.

[ghost flanker]

Cyco-Dude, going_home, and athomas,

I have to say you guys were on point about the frame being the culprit. I was mistaken about the make of the frame though; it's a Kapp, not a Benchmark. Anyway, my friend put an AGD pot metal frame on it and said it shot nice and snappy. You guys were right. Probably due to very close proximity between the trigger rod and the trigger pivot point exactly how Cyco-Dude described. I appreciate all the help.

[Cyco-Dude]

Cyco-Dude, going_home, and athomas,

I have to say you guys were on point about the frame being the culprit. I was mistaken about the make of the frame though; it's a Kapp, not a Benchmark. Anyway, my friend put an AGD pot metal frame on it and said it shot nice and snappy. You guys were right. Probably due to very close proximity between the trigger rod and the trigger pivot point exactly how Cyco-Dude described. I appreciate all the help.

keep in mind it's not bad, it's just different. kapp frames (kapp groovy?) with some hogue palm-swell grips are pretty comfy too!

[Spider-TW]

If you like the frame otherwise, I have filled in the back side of a benchmark trigger pocket with solder to bring the pocket back to the AGD shape. You could probably use some red loctite on a tiny half round of brass back there also. After I got the trigger setup, I still didn't like playing with the shape and width of the frame, so it turned out as more of an experiment.