Nice work! +1 for you. How was the accuracy effected? What FPS are you at with no hop and with various amounts of hop up added?
Top-Down Hop up
9
I had this problem with my hop up. I've been experimenting with extremely long hop up contact patches. My problem was traditional hop up systems applied pressure to the patches at an angle. This made for improper hop, or, rather, not fully used hop. It was almost impossible to apply flat, even pressure along the full length of the contact patch.
So I had an idea. If I could put a screw, or something similar through the top of the gun into my hop up chamber, I could give the hop up a more even contact surface. Simply by pushing the furthest part of the hop up down would help out; the rest of the chamber could hold the nub in place, and keep it centered well enough.
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These are my hop ups, the top is a Prometheus chamber, the barrel is vanaras 6.03 509mm, the bucking is a Prometheus Hard, the nub is an M-nub backed with metal, and the hop up is an XR-hop.
The second hop up chamber is a Madbull Ulitmate with a Prometheus 6.03 550mm, Madbull Red, sorbo nub backed with thin plastic, and the contact patch is a long flat hop contact patch.
The solution was simpler in my mind that it actually was to make.
I started by drilling a hole through the top of my gun, straight down, over the hop up unit. The first hole was too close, and the second one was right on spot. You can see the Prometheus's pink arm through the holes, to get an idea of where the screw is centered over the hop up unit.
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Once the hole was made, I JB welded a nub to the underside of the gun:
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The screw I used I modified to be easier to turn with gloves from outside the gun. I removed the head of the screw and added a dial I found at Ace. It turned out to be perfect for this application.
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These last few pictures show how it all comes together, and about how it all fits together. All in all, I'm quite pleased with how this came out. It was fairly simple to implement, and is remarkably effective for the longer contact patches.
It was really interesting to see it start to take effect. Because of the way I have the hop ups set up, I set it normally at first. Then, once I get the correct amount of hop, I start to apply hop with the screw until I notice the bbs starting to hop more. What's really interesting is, as I start to screw the screw in further, the range of the bbs begins to increase. I don't know what spring I had in my gun, nor do I know what it was chronoing at at that matter. Using Matrix .28s I was getting about 200-250ft of range during the initial hop up setting. Once I set the secondary part of the hop up, I was getting 300-350ft of range. I was very impressed, and it was really interesting to watch the range slowly stretch further and further, without adding any extra hop, as I screwed that screw in.
As for the name, I was discussing this with a sniper friend of mine, and it turns out Noobie did something like this a while back. So, the name is his, considering it's the exact same thing he did, just, this is in an aeg, and not a vsr-10. But, regardless, I figured I would share the mod, and show how I did it to my L85.
So I had an idea. If I could put a screw, or something similar through the top of the gun into my hop up chamber, I could give the hop up a more even contact surface. Simply by pushing the furthest part of the hop up down would help out; the rest of the chamber could hold the nub in place, and keep it centered well enough.
These are my hop ups, the top is a Prometheus chamber, the barrel is vanaras 6.03 509mm, the bucking is a Prometheus Hard, the nub is an M-nub backed with metal, and the hop up is an XR-hop.
The second hop up chamber is a Madbull Ulitmate with a Prometheus 6.03 550mm, Madbull Red, sorbo nub backed with thin plastic, and the contact patch is a long flat hop contact patch.
The solution was simpler in my mind that it actually was to make.
I started by drilling a hole through the top of my gun, straight down, over the hop up unit. The first hole was too close, and the second one was right on spot. You can see the Prometheus's pink arm through the holes, to get an idea of where the screw is centered over the hop up unit.
Once the hole was made, I JB welded a nub to the underside of the gun:
The screw I used I modified to be easier to turn with gloves from outside the gun. I removed the head of the screw and added a dial I found at Ace. It turned out to be perfect for this application.
These last few pictures show how it all comes together, and about how it all fits together. All in all, I'm quite pleased with how this came out. It was fairly simple to implement, and is remarkably effective for the longer contact patches.
It was really interesting to see it start to take effect. Because of the way I have the hop ups set up, I set it normally at first. Then, once I get the correct amount of hop, I start to apply hop with the screw until I notice the bbs starting to hop more. What's really interesting is, as I start to screw the screw in further, the range of the bbs begins to increase. I don't know what spring I had in my gun, nor do I know what it was chronoing at at that matter. Using Matrix .28s I was getting about 200-250ft of range during the initial hop up setting. Once I set the secondary part of the hop up, I was getting 300-350ft of range. I was very impressed, and it was really interesting to watch the range slowly stretch further and further, without adding any extra hop, as I screwed that screw in.
As for the name, I was discussing this with a sniper friend of mine, and it turns out Noobie did something like this a while back. So, the name is his, considering it's the exact same thing he did, just, this is in an aeg, and not a vsr-10. But, regardless, I figured I would share the mod, and show how I did it to my L85.
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I'm pretty sure this is how the system he uses works, thats how I would do it at-least. Its very similar to the Tanaka and KJW 700-series hop-up just with an added hop-up arm and an extended patch. MS-Paint!
2
A guy on Airsoft Retreat called Noobie made something like this for the VSR 10. He called his a TDC (Top Down Center) hop up. It's an awesome system, his has custom hop up arms with a screw hole in it so the thumb screw will always be pushing down in the center. I am lucky enough to have gotten a hold of one of these hop units, and his awesome M-trigger.
Heres some pics of my VSR hop:
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here's the link to Noobies TDC topic on ASR http://www.airsoftretreat.com/forums/index.php?topic=86871.0
Heres some pics of my VSR hop:
here's the link to Noobies TDC topic on ASR http://www.airsoftretreat.com/forums/index.php?topic=86871.0
3
Sadly this is all old news to some of us at the cutting edge :
Firstly can I correct you all......
TDC stands for Top Dead Centre, cuz that is the point of contact for the adjuster!
Noobie did not invent this style of hop, and even says so himself.
I've been running a TDC + long hop in my EMR and my 350 fps VSR for a very long time now, and I even made 1 for my CA M24 about 6 years ago.
I've even been running a system similar to starfolders in my EMR for the last 8 months because of the same problems he encountered, only I use 2 M4 bolts side by side that are exactly the same length and marked up the same, so I can adjust them the same amount, so I know the nub is going down at the same flat rate..... The only thing I havent done is the extrrrreeeemly long nub, mine is only 10mm long.....
Pics of version 1....... Version 2 was similar with minor mods...... Version 3 is the current 1 under test, including the twin bolt system
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Firstly can I correct you all......
TDC stands for Top Dead Centre, cuz that is the point of contact for the adjuster!
Noobie did not invent this style of hop, and even says so himself.
I've been running a TDC + long hop in my EMR and my 350 fps VSR for a very long time now, and I even made 1 for my CA M24 about 6 years ago.
I've even been running a system similar to starfolders in my EMR for the last 8 months because of the same problems he encountered, only I use 2 M4 bolts side by side that are exactly the same length and marked up the same, so I can adjust them the same amount, so I know the nub is going down at the same flat rate..... The only thing I havent done is the extrrrreeeemly long nub, mine is only 10mm long.....
Pics of version 1....... Version 2 was similar with minor mods...... Version 3 is the current 1 under test, including the twin bolt system
1 - 17 of 17 Posts
