Any one with experiance with flat-hops?
 

Just ordered a modify Flat-hop rubber and nub combo for a LCT AK hop up unit with a tight bore barrel. Anyone have any experience with these nubs/rubbers?

lazy man's r-hop... basically you put the sleeve on like any other. The nub is a little taller to compensate for the fact there's less material where the mound normally is.

What's the question exactly?

It shoots straight, yes.
I have one in my G36, but if I had the hardware required, I would r-hop it.

Edit:
Beat me to it.

Sorry the question I guess is what to expect, what to look out for. What kind of performance bump I should expect. (right now using a pommy rubber and a standard nub.)

I am a relative newb to arisoft, this will be my first do it your self project (had been using gun docs previously.)

R hop seems way to difficult for me as I do not have easy access to a range and pulling apart my gun multiple times to sand my rhop over and over seems a bit much for me ATM.

This is the combo I ordered. Thought that the fact the rubber does not need modification and is designed to go with the nub would work best.
http://www.airsoftparts.ca/store2/in...oducts_id=2466

Nothing wrong with the flat-hop, don't let the "lazy" word discourage you.

Before changing the hop-up rubber, I would make sure you have no air leaks and a consistent FPS (which is consistent because of the lack of air leaks... I digress).

The performance bump cannot be measured, but there should be one. Just be sure that the new rubber sleeve provides a good seal, or mod it so it does. An air leak will kill your performances and leave you with poor accuracy.

If it's your first hop-up change, I would read a lot of guides on how to do it, because if you screw something, you gun will shoot like crap. That doesn't mean it's hard to do, but you should know what you're doing.

air seal is everything, if you have an inconsistent seal before, you'll have incconsistent accuracy, with a new rubber, same deal. Piston o-ring, cylinderhead to cylinder seal, nozzle to cylinder seal, nozzle to hopup chamber/bucking seal. Any one of those leaking will affect accuracy.

I've heard mixed reviews
mostly good though
I've used two modify flat rubbers to convert barrels to R-hop. The flat nub is GREAT for use with R-hop, but the rubber I found was on the hard side. One was okay, the other I had to sand the mouth a bit because it was too difficult to push a BB past.

Honestly I would stick with a PDI-W or firefly though, they have more consistently awesome performance reviews

I have that modify setup in one of my aks. I like it. Its a bit more consistant.

W hold is great as a standard bucking. If you're going to spend as much on a flat bucking or bridge/flat hop nub, might as well just r-hop lol... not that much more in cost, and better performance. To get the best results though, shave a soft rubber for better seal instead of a harder rubber.

Or better yet, take your favorite hop bucking, shave the inside and put the flat hob tensioner with that and save the cost of buying an overpriced sleeve.

The nub in the Modify kit is a bit undersized laterally and unless you center it correct across the arm, you'll get curved shots.
The sleeve also isn't universally that good, for the reasons stated above.

An R-hop installation only requires you to remove and disassemble your barrel group once. Where did you hear that you had to take it apart multiple times?

Lastly, even an R-hop with a standard round nub will blow a flat-hop setup out of the water. And that's fact.

when the barrel lies to you by letting a BB pass through fine with the rhop patch on... then hops to the moon when fully assembled at 0 hop setting. :P

LOL wut? I've been able to underhop 0.20g. Check yo nub

Telling you man, this install method works.
AEG Accuracy, Hop-up and R-hop Install Tips - YouTube

I've gone through your vids and maekii's and HS5s.. every one I've installed had to be pulled and inner radius sanded. Even my first 2 with the mnubs. With 0 setting it still hopped.

Might be something to do with the natural "0" hop setting on platforms OTHER than AR15s...

Between the 3 of us (maekii, HS5, and me/us) we all use M4/M16 hop units.

that's possible, I've done a p90, 2 g36s and a 416... tho the 416 also had to be inner sanded. But once you silicone oil the inner radius and use the installation tool with some 800 grit, it's polished extremely well. you have to let the sandpaper do the work.. takes time but you can take down the inner and retain function. The trick is if you are working on the inner side, you tack the patch down with glue to the installation tool so it's braced and you're free to wrap sandpaper around the rod and sand the inner.

The p90 and my g36 use mnubs, the other g36 uses a standard cylinder nub and the 416 is setup to use the prommy bridge nub. 2 madbull and 2 prommy EG barrels between the 4. They all work really well though the 416 needs a barrel lockdown kit, when you leave the bolt closed it throws off the hop, which I think is just the hop unit being pushed to the side when it's closed.

I am using an LCT AK hop up. This is for my CYMA RPK. I also am using a 509mm 6.01 madbull.

Ok dumb question here.

If I am reading right you still use hopup/nub pressure on an Rhop? I was always under the impression that Rhops provided there own intrusion into the barrel that made applying hop irrelevant.

IF you do still need to apply hop pressure in an rhop would you be able to combine a flat hop nub with an Rhop system?

a flathop nub is generally taller than a standard nub or the prommy bridge nub. It has to be taller because there's thickness on a standard bucking where the mound is. The rhop patch fills this void and you shave the mound off the bucking.

A flat hop setup has no mound, just a cylinder of rubber so if you used a regular nub, your hopup adjustment wheel would bottom out and there would still be no protrusion of the rubber material into the barrel to initiate hop.

Rhop isn't magical it still works the same way as a standard hop setup, it just replaces the mound with something that's a far more consistent shape. You can use a standard cylindrical nub, a block of eraser, HS5 m-nub, or a flathop nub. Though block shaped nub replacements work best once it's all working properly.

Depending on how much protrusion you get is how you know you need to sand more on the patch which is what can make an r-hop install tedious.

That would be fixed hop, that would be bad.

Stealth, not everyone is as good as us, lots of people doing R-hop need to take the barrel group apart to tweak it afterwards.

Knight, sorry dude, you're not doing it wrong, but you're testing your work wrong.

I've done over a dozen so far and only the first and one other had to be re-worked. Once I nailed down my testing method I never had to go back and tweak a patch. It's all about your testing.

dude, BBs push through fine with a naked barrel and rubber, they don't push through fine when it's all packed into the hopup unit, that's that. After adjusting they all work fine though and they all have great accuracy.

Maybe I just have bad luck and all the barrels I've done are in between the kit patch sizes. A couple required less adjustment than the other 2. It's the nub size that seems to push it down at 0 hop. I've asked HS5 about it and he said it was luck of the draw, if it still shoots straight after needing that much rework then it's still installed right, it just takes longer.

I use the modify right now, I pretty much try any hopup version, I am very impressed with the flat. You just have to modify it to your set up or tastes.

Do not use the junk rubber that came with it. Grab a quality one, I use the Systema Energy, cut off the nub and sand flat, or even better, cut off both that and the groove channel, and flip the rubber around so that you have a 100% clean patch to use for the hop, I got extremely good results from doing that.

You need to super glue a tiny extra peice of rubber to act as a shim between the hop arm and the rubber, I noticed it needed a bit of extra firm and hop to it to really perform.

As Stealth said, it has to be perfectly centered, it takes a few tries to do, but when you do it like I found, it really is top notch.

I've had two other guys have the same issue your having, where the Rhop applies pressure after it's been assembled into the hop chamber.
I've only noticed it on the second one I did, but I adjusted my installation method to compensate for any compression pressure from installing it into a hop chamber, and I make sure the rubber sleeve is 100% flat on the inside. I haven't had any recurrences of having hop applied after the fact.

You just have to identify what's going on, which you've already done, and then adjust your testing and installation methods

Maybe a picture tutorial would help... maybe I'll publish one... some day...

Wow i didnt think the modify rubber was all that bad sheesh. It performs very well in my ak with very little fps deviation. Gonna have to experiment with softer rubbers.

softer hopup rubbers seal better for the nozzle side... but aren't terribly great for lifting heavier rounds at higher fps.

harder rubbers don't seal as well but lift heavier rounds much better. This is why the Rhop is good.. the material is a reasonably hard tubing that lifts heavier rounds very well, but you combine it with the soft, best sealing shaved rubber of your choice for the best of both worlds.

I get how it works i just have fine performance with the harder modify rubber i am using is all. An interesting concept for sure. I dont pay too much attention to most airsoft fads. At least this one has some thought behind it.

reaps was a fad. magpul is a fad.

r-hop is results.

Haha good one.

SCS was a fad lol

Well I won't have access to a better rubber so I will press ahead with the modify rubber that comes with the kit. It should arrive tomorrow and I can test it on Saturday or Sunday. I will post an update.

Your gun doesn't come with a hop rubber?

Please. Flat, R and whatever else is out there beyond stock. :)

A picture tutorial for these mods would be awesome.

I didnt like the flat hop due to what stealth said (not sized correctly shots pull to one side, even if you get it centered itll slip out unless you glue it in place)
I went with the prometheus smooth rubber and bridge tensioner. Works great. Way more hop for lifting heavy rounds and it does it consistantly and evenly (no pull to either side)

"Your gun doesn't come with a hop rubber?"

Well it does but want to get a game in this sunday so I need a roll back plan it the flat hop shits the bed. IF I shave my current rubber and the flat does not work I'm screwed till I can get another rubber.

a wise man once said... always have extra rubbers.. never know what might happen.

What hop unit are using? I have the flat hop in my ak with a lonex hop unit and the nub fit just fine. It didnt seem too small or anything for me.

G-Hop is the real lazy mans R-Hop - less fine tuning.

Results (from what i've read) are comparible between the two with R-Hop having the slight edge (again if you have the patience for the fine tuning.)

R-Hop is just HS5's advancement of the G-Hop.

Stock round nubs work - but most use flat nubs or the HS5 m-nubs.

Ok so as promised I did the flat hop mod. I also installed a 6.01 barrel at the same time
(from a 6.03 both madbull) so it was pretty hard to determine what was the cause of the improvement. The gun defiantly has more range and tighter groupings. From what I read I think i would have expected that from the barrel alone though. The Flat hop seemed to neither help nor harm the overall performance.

It's the hop rubber giving you improvements, I'm getting tight groupings from a 6.10mm barrel. There's absolutely no reason for anyone to ever install a barrel smaller than 6.03
The bore size of a barrel doesn't magically give you more accuracy, only the consistency of the bore matters.
The tight and longer the barrel is, the greater it's chances of reducing accuracy by fouling.

anyone tried crossing "fads" (haha) ... and putting a flat or rhop with a TK twist?

we've seen great results from the flat here on the island (namely in M4's the choice combo to date appears to be prowin hop unit, flat hop and madbull 6.03

I personally haven't had a flat hop be 'sideways' on me (maybe I'm just catching it during install?) and seen great results from 340fps too 400+ ... including an M4 based DMR doing honest 200ft repeatable torso shots just under 400fps ...

no ones had a functioning Rhop on the field yet... but I'm just coming out of just over a year of retirement from smithing and airsoft in general ... so it's next on my list (very few builders/proper smiths on Van island)

so the point of that above LOL is .. I quite like the flat hop... see if a proper Rhop will be worth the effort over the 'lazy man' flat hop



Edit: THANK YOU Thundercactus for your words on the barrel thing... I find myself constantly argueing with people over them HAVING to put in the longest tightest barrel cause they heard it was awesome on youtube...

Next time I find a stock MC-51 or the like with a reasonably short barrel (~250mm) for sale we need to do that low velocity mod I was thinking with the rhop and the tk twist. I'm suspecting it might prove to be extremely accurate at mid range.

With everyone using the term "flat hop" are you referring to merely the hop up nub being flat?

Or does this term refer to something else I'm not aware of.

Flat hop means a flat hop sleeve and flat hop nub

There's no reason a tk twist should give better accuracy over an orga widebore, but may give better results than a 6.01
The tk twist is effectively a widebore barrel, that's how it works

Hold on a minute. Just because I can't hit the side of a barn door doesn't mean the r-hop patches in my VFC HK417 and KWA M4A1 aren't functioning. :D

my p90 with a 247mm madbull has better accuracy and consistency than most AEGs on the field... people always look at it and ask wtf kind of virgin pixie dust is spread all over it.

this + 1

ive seen setups that make no sense on how they get the range/acuracy that they do.

like my 6" inner barrel (152mm) M4 shooting roughly 315fps can reach out and touch people easily beyond 200ft.

I really really wish there were verifiable consistent lab quality tests of all these setups. The contradictory information makes choosing what internals to get impossible. For what ever reason my groupings came down an average of 2 inches at 150 feet, and I felt (but did not test) my effective range improve.

the prep and setup are usually more the defining factors then the parts used... I don't care how much you've spend on parts or what brand they are.. or what thousand your gun cost... if it ain't consistant, if the hop up chamber is moving around.. if the barrel is moving..etc etc... all the money/brands chest beating ain't gonna do shit.

Its very simple
This isn't real steel, longer barrels don't equal more accuracy
A 6.01 barrel will theoretically have the same accuracy as a 6.10 barrel, but the 6.01 will foul faster causing accuracy loss after just one mag.

With my VSR's 6.03 barrel I noticed accuracy loss due to fouling after just 120rnds

The BB isn't actually supposed to touch the barrel at any point after the hop, its just a cushion of air that guides it centered down the barrel. So whether its a 6.01 or 6.10, the physics are the same, they both use air pressure to center the BB, just one has more room to allow for fouling.

The same goes for shorter barrels, beyond a certain length, once a BB is stabilized its stabilized and no extra amount of barrel will make it any more stable.
Case and point; compare a stock M16a3 against a KSC USP
The USP gets very comparable range despite having a 4" barrel vs the M16s 20" barrel.

Too many variables at play.
Platform variations, installation skill, tuning time, consistency, manufacturer tolerances, I could go on.

All else being equal, the best possible AEG barrel group setup has been accepted to be an ER-hopped/EM-nubbed 455mm 6.03 stainless barrel with the barrel consistency as high as possible and a good-sealing rubber. I've tested this theory personally by swapping an identically set up 363mm and 455mm barrel group, keeping the same lower receiver the same. Ignoring barrel volume for a second, the grouping size and range was noticeably better with a 455mm barrel. I do recognize that not everybody wants to run a 16" barrel AR-variant or a full-length AK, etc. so the 363mm is a good tradeoff. I have another barrel group at 230mm that I'm going to try when I get back.

Flat-hops are nice but it's just an evolutionary step towards the R-hop. I'll say this again: a proper R-hop install should not take more than 10 minutes more than a Flat-hop setup (excluding dry time).