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VSR Hop up Arm Comparisons-Dangerwerx Arm

41380 Views 79 Replies 20 Participants Last post by  foxactual
More details to come for grades given to hop up arms....stay tuned


Recently got in touch with DangerWerx, a member on some of the other forums that a few of you guys may know or have at least been reading up on some of his custom works.

I was able to get a hold of one of his custom VSR hop up arms. With that said, I told him I would put together a review for him, and compare it to some of the other hop up arms I have used in the past.

With that said, this review will deal with the hop up for the VSR 10. The arms in comparison will include the stock arm, the PCS modded arm, the rubber o-ring hop up arm, and the Dangerwerx arm. I will start off by describing and linking some information (copy and paste for most part) from the hop up arms I have used in the past and will rate them on a scale of 0-100. 100 being the best obviously. ;)

So buckle up, here we go!!

1. Stock VSR hop up arm: No mods, straight up standard hop up arm. When I first received my VSR 10, I used a stock arm with a non-modified hop up chamber, nine ball bucking, and EDGI barrel. Results were not bad, but immediately noticed a curving issue to the right. After some research, it became apparent that this is an extremely common issue with the stock VSR hop up, but some shims would solve the issue. So I added some shims....


Shimming the hop up:

First off, I went to the hard ware store, and unfortunately, no brass shim stock was available. However, I decided I could use something that I had at home, and that was note cards (suggested in Rick's linked thread). All you need is some note cards and Elmer's glue!

Note cards, being thicker than standard paper, seem like the perfect fit. Nice and smooth, and can allow for the arm shim to not get in the way of adjusting it back and forth. But at the same time, it keeps the arm from moving freely.

I applied some glue to the bottom of the shim and flattened it out with a flat head screw driver (more steady/smooth than using your fingers.)

I moved on to the arm next, and carefully cut out another shim.

I still need to let the glue dry before testing to see if the note card is too thick to allow the adjuster piece to slide in there.

Next up, the more tedious shim job.

Two pieces, was easy to do, just a tad more time consuming.

And here is all three shim jobs together:

Total time was roughly 15 minutes, very easy to do, and can be re-done if necessary! Only things you need are scissors, note card(s), glue, and a somewhat steady hand. I also found a phillips head screw driver/flat head screw driver was useful for cutting holes and flattening out shims.

For more pictures, see this thread:



Anyways, going into Saturday, shots were straight and consistent for the most part but as the day went on I started getting some good curve to the right. I was thinking the hop up arm shim started to wiggle up leaving me with more pressure on one side than the other, resulting in the curve. I have yet to take the rifle down, but hopefully I can figure it out shortly, before trying to dish out the cash for a new Precision chamber.

I managed to take down the chamber, and removed hop up shim as well as the shim on the base of the hop up arm. I put her back together, and took a few shots. I noticed that with the hop up set the same amount as usual with .3bbs, it was going a bit down. Therefore, the hop up shim arm DOES in fact make a difference in the amount of hop on the bbs. What I am unsure of, is how CONSISTENT the notecard shim was in relation to hop.Shots were going dead straight (considerable amount of difference than from before) as well as a increase in distance. I am getting out an extra 20-25 feet than I was before. I was not able to pop off a lot of shots, but so far so good. I am interested to see if I start getting some curve action again. The only thing I could think of would be that the bucking sneaks out of position when in the chamber. Let's hope that does not happen. It is about time I am able to zero her in and let her enjoy the summer.

After some more shooting today, I was getting some more curving again. Same thing as before, curve to the right. It seems the bucking comes out of place ever so slightly. That is the only thing I can think of, as every time I go back in to realign it I get some straight shots for about 50 rounds or so.

Tried using tape on fangs of the arm to compensate for curve right.
Results: Curve left, but could not get it to shoot straight.
END RESULTS: Never got it shooting the way I wanted it to....Hence round two below

Grade: N/A--Its like doing half your homework and then turning it in. The part you did is great, but the half you didn't work is no good. I walked away from this to try different mods. I had plans to add a anti-flex plate but never got around to it. With that said, saw potential in this set up, but moved on to other mods to experiment a bit.


I did the Shredder mod after getting the metal files and stuff together from the hardware store. Can't say I am happy with the work, but curious to see how it works out.
To start off the morning, I installed the PCS and put the rifle together, noticing a significantly large bulge inside of the rifle. It was slightly crooked but I decided to give it a whirl anyways. Keep in mind, the shim on the arm is still installed, so expect HUGEEE hop or jam right away.

Now with that said, keep in mind, I don't exactly have the luck of the irish, and my four leaf clover is still in my jeans from yesterday, so I was on my own for this one. Went outside, took a shot, and guess what...? Jam..

Round Two:

Decided to do a bit more filing, nothing too significant. Then I removed the shim on the hop up arm. With the PCS, getting hop is not a problem. So no need for extra hop up due to a shim on the arm. With that removed, much easier to install pieces on top/inside gap on arm.

Went out for a test shot, using .3s, and about 15-20% hop up on. The bb flew up a good 60 feet in the air. Very very large amount of hop on that one. I didn't even bother adjusting the hop up for .3s, as it was time to get the big boys out.

Got out the ol' madbull .4s, and gave her a go. Took some shots, with about 10% hop up on, and they're flying. A tad bit curve to the left but not near as bad of a curve as before, where you could literally hit a guy hiding behind a tree...

So so far I am happy. Not sure if I want to mess with it anymore. I already filed a good bit and I am going to zero her and see what happens.

More updates to come.
I am relatively happy with it, especially compared to how it was before. I am literally getting .4s out there on basically zero hop. I feel like buying some crazy weight like a .83 just for giggles.

Anyways, going to play a small game with it, see how it goes. If all goes well, no need to fiddle with it anymore before Saturday. I am hoping to get a custom arm soon and this is basically just to hold her off so I can get some action with it.

Thanks for the input in the thread!
Update after LP game: (there are a few of them...)

1. Started out the game using some .4s, PCS nub, and all was good. Went to the chrono station, found my rifle shooting 380 fps (with .2), rather than the 410 fps two weeks earlier. Did not think much of it, as compression and consistency was still spot on. Not bad, considering teflon tape mod prob. wore down a bit.

2. Day went by, PCS doing a good job of carrying the .4s, overall happy as day went on.

3. Last game of the day, trouble started. Was taking some test shots out on the field, adjusted the hop up to 70% for a "test" and got a jam. Turns out that the hop up cannot be set too much otherwise you get too much hop which then results in the jam. (nubbin blocked hole where bb goes through.)

Fixed the problem by adjusting the hop up back down to the lower setting (opened hole where nubbin sat).
END RESULTS: Ehh...definitely a improvement over the stock arm, but way to much hop even on the lowest setting. It was also extremely inconsistent out on the field, even with .4s. Overall, it sufficed for the time being, but being the perfectionist I can be sometimes, I strived for further improvements. This brings me too round three!!

Grade:79- While this mod proved to be beneficial in the time that I used it, it also was not the best solution to the problems I was having. The inconsistencies were the major issue, and left much to be desired. There was also too much hop that I never really got under control. Overall, I give it a C. It provided decent results, similar to that of a stock rifle, minus the curving issue apparent in the VSR 10 series rifle.

For pic reference, see:

3. O-ring Modded Hop up arm:

Did this mod on the fly, right before a game. Saw someone talk about this mod online and decided to give it a try. The object of this mod was to shave down the original hop up arm, just enough so that a small o-ring could go over top and around the hop up arm and sit on the fangs. This would in theory, help provide even pressure on the hop up arm.

The results were actually quite impressive, a big step from the PCS mod. The shots were much more consistent, and while less pressure was now applied to the bucking, I still had enough hop to push the .4s out to a pretty good distance. I was pushing around 200 feet accurately with an SP130 spring, which clocked out at about 375 fps with .2 gram bbs. Not to shabby if I say so myself...

However, there were a few problems. Occassionly the o-ring would slip off the fangs and sit on the side of the bucking, rendering itself useless. Shots became less consistent and since the fangs were shaved down, the pressure on the bucking would become susbstantially less.

In addition, when adjusting the hop up for different weight bbs, the o-ring would slide around and snag on the side of the chamber. This sometimes made the pressure on the bucking a little "off" and curving would occur.

Overall, this was a decent mod that when installed right, was actually pretty nifty. Got rid of the curving issues most VSR models have while at the same time keeping shots relatively consistent.

Grade: 91 Proved to be a worth while mod, and a rather significant improvement over the PCS mod. Consistency went up and the amount of hop on the bbs went down in comparison to the PCS version. However, compared to the stock hop up, the o-ring provided much more hop and could carry a .4 on about 50% setting. While consistency increased, I was not 100% happy with the mod. There were a few shots here and there that "escaped" the normal line of fire, and these imperfections proved costly on the field. Granted, towards the end of the reign of this mod, it was near winter, when the winds picked up substantially and proved to affect shooting quite a bit. If anyone needed a home made mod, this would be the one to try and would be relatively happy with it. A high B for the o-ring mod, although I am sure some will find it to be "A" worthy, as it truly is a useful mod.

Groupings:Standing Position, no bi pod, minimal winds, .4 madbull bbs, 100 foot distance

DangerWerx Arm:

Got two of these from DangerWerx himself to do some extensive testings and such, and upon receiving it in the mail, was very excited, as this particular hop up arm was designed very differrent from previous used arms. Rather than the fang system, the Danger Arm involved one single mound across the arm, resulting in more pressure on the bucking then with a standard arm. I am able to push .4s out with minimal hop adjusted (about 30% on).

The Danger Arm is CNC machined, and is custom made to fit the VSR 10. The single mound results in even pressure on the bucking and bb, and will help increase consistency over the stock arm as it is not plastic (which bends often).

One of the things to note though is that right curve can occur with the arm still due to the slider hop up adjuster (with the pin that goes inside the arm) coming out a bit, resulting in uneven pressure applied to the bucking. One of the things I wish TM did was...
1. made a anti flex plate
2. Provided two drilled holes instead of one so that two shims could be applied to the hop up slider piece, which would prevent bending, resulting in even pressure applied to the arm....or just made the hop up parts out of a quality bending, no problems.

However, I dealt with that by adding a piece of thick card board to the hop up adjuster piece, placed a shim on top, and this has helped keep the hop up adjuster piece down, and not popping up.

If there is one thing I wish someone would do, that is to make a metal anti flex plate. It is not exactly hard to do, but I unfortunately do not have the tools to do so. If anyone is interested in dimensions and would like to make a prototype, let me know and I can get the numbers for you.



Some things to note about the DangerWerx Arm:

1. It seems to be a tad thinner in size, as it leaves a bit of wiggle room in the hop up chamber in comparison to the stock arm. I simply applied some scotch tape as a shim (idea came from another user of the arm, thanks bud!) and this helped tighten it up and prevent unnecessary wiggle.

I would post a pic of the shim, but it is clear tape, and is simply applied in the same areas as the note card shim was applied above in other arm mods, with the exception of inside the hop up not need more hop then I already have.

2. You will be producing shots with more hop. In comparison to other mods, with the exception to the PCS mod which gave wayyy too much hop, this arm will provide more hop and ability to use heavier bbs without having to increase the fps output. For those of you with small FPS limits, you can easily run under 400 fps and still use your heavy weights if desired.

3. Like said before, the design is great, and provides even pressure on the bucking. This is the most evenly pressured you can get, as with previous mods, all was done by hand, and small variations could occur. (slightly unbalanced, etc.)

Therefore, the Danger Arm is perfect for you perfectionists, and will fling the bbs out without any side spin due to uneven pressure on the bucking. Please note though, any variations such as wind can cause curve, so keep that in mind when hitting the field.

Not much more to it than that. I recently got some testing done today and from weeks ago, but unfortunately heavy heavy winds prevented solid testing from taking place. I still need to get some shooting charts up so that you can compare the various hop up arms to each other and check out the groupings.

If you have any questions please let me know. Pics and more pics to come.
-shooting comparisons
-Grade of Danger Arm---Postponed until extensive testing in suitable weather conditions occurs. Stay tuned.
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You might find my experience with hopups interesting. My Bar10 has the same hopup arm as the VSR10(ofcourse) and awhile back one the arm's knubs broke. I was at a game and some quick thinking of a friend managed to solve the issue. He took one of my bb's, chopped it in half with sidecutters, cut off the other arm's knub and dropped the half bb in place of the knubs.

A diagram I stole from dangwerx:

The first shows a normal hopup arm side and front view(x'ed out). The second is my current setup.

This is how I have kept my rifle for a year because it shoots extremely well(and I haven't had time to experiment with enough other possibilities). The interaction it has with my firefly bucking is quite interesting though. The curvature of the bb pushes the knubs of the bucking outward evenly and I think causes my bb's to shoot quite straight.
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Very interesting stuff Kreeper! If this does in fact work, I could see an arm being CNC machined to form the shape of the bb instead of the fangs. Have you tested it with other buckings?

Also, so far the Danger Arm and Cheese Man's flex plate is working together beautifully.

I added an extra shim to the anti flex plate to provide more tightness overall across a larger surface, and am getting solid results.

Using a modify bucking and some washed madbull bbs at this time. Going to get some test results at 100 feet and compare them to the results I had with the old o-ring modded hop up.

Kreeper, if you can, can you get some groupings at 100 feet up? Would be great to compare them to the ones I have and see which hop up design suits the VSR the best. I'm all for new ideas and improvements!

Wow! That bb idea sounds really great.
Now, anyone have any bbs?
Jokes aside. I think i'll test it, when I get my gun a piston and a spring guide, then we'll see how gspec that shoots ~450 fps with stock barrel and nineball bucking.
Wow! That bb idea sounds really great.
Now, anyone have any bbs?
Jokes aside. I think i'll test it, when I get my gun a piston and a spring guide, then we'll see how gspec that shoots ~450 fps with stock barrel and nineball bucking work with this.
With goldenball 0.4g and blaster devil 0.25g.
The only other bucking I have is a King Arms which is much stiffer and thicker than the Firefly(hard). Because of the size of 1/2 a BB, it pushes too much on the King Arms and immediately over-hops the bb. I'll try and get the range shots for you this weekend.

I have essentially tried:
King Arms w/ 1/2 BB
Firefly(hard) w/ glued 1/2 BB
Firefly(hard) w/ 1/4 BB
Firefly(hard) w/ glued 1/4 BB
Firefly(hard) w/ glued plastic piece

None of these seemed to work and I really haven't been motivated to buy another hopup arm because my current setup has worked so well. Though, I may still end up getting one to do some tests.

Now there are draw backs to this. Due to the BB curve, it gets the bucking knubs caught on the edge of the bucking's barrel slit when you are putting together the hopup so you need to be extra careful about BB placement and the bucking knubs cleaning make it into the barrel. Once it is setup, even with hopup all the way off, the bucking knubs don't go far enough down to get caught against the barrel slit edges. I hope that makes sense. If you need a picture let me know.
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Does this explain the firefly bucking?

oh! You mean nub!
Maybe nineball bucking isn't as stiff as king arms. Have you tried to sand the bb smaller to get less hop with king arms nub?
Danger, have you thought about making an arm that is shaped more like what a PCS nub is shaped like? So instead of a flat nub across the arm, more like a "PCS" shape. Just a thought!
Interesting idea Finland. I am not gonna mess with the bb that works now, but I may try and cut another bb and do that in the next couple weeks.

Haha on the knubs. I found out knub is derived from nub due to the influence of the term knob.
I think I am going to buy the type B some point soon here.

"Type B Is best Suited for H-Type or W-Type Hop Up Buckings" H type is Firefly, correct?
I think I am going to buy the type B some point soon here.

"Type B Is best Suited for H-Type or W-Type Hop Up Buckings" H type is Firefly, correct?
That's correct. Type B worked nicely with my nineball buckings. I can reach out to 240 ft easily.

I have thought about a pcs style arm and it was actually one of the things keeping back my release.

Because the type a and type b have a more simple nub, the $ is lower.

Translating the sloped contour of the scs style would have been an additional operation. A true concave tip would be expensive, but I will probably release something with a curved profile, but missing the true concave detailing.

The single bump is an interesting idea.


Yes, a type-b would be more ideal for the firefly bucking

Ya might have even better results with a type-A :D
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lol I'm confused. Type B is more ideal yet type A might be better?
He said it to whisper.
Have you thought about doing r hop hop up arm? It would be a longer part that presses on to the bucking. But I quess the angle it presses would make it not press with it's whole surface..
Haha, oh. I thought he was *whispering* to me.
lol I'm confused. Type B is more ideal yet type A might be better?

For you, using a firefly hop up rubber, a type-b hop up would be ideal because of how it interacts with your hop up bump

For Whisper,
who is using a nineball hop up rubber, the type-a arm would be ideal because of how it works with the flat hop up rubber.

I am currently working on getting a bump-less hop up rubber done for the vsr-10, and a corresponding arm to go with it.

I am unfamilar with the R-hop, I have read about it, but would rather not venture into something I have no solid information about.
Google hunterseeker armory, he is selling r hops.
Also check airsoft mechanics, there is a lot of talk about it at advanced technical.
Ps. Bumbless bucking is perfect for r hop!
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