Hop up unit, rubber for DMR? (approx 475 fps)

[airsoftjunky]

I recently purchased a King Arms BW15 with the intention of turning it into a dmr type gun. I plan to disable the full auto function and have it just semi auto. One of the first upgrades I want to do is a hop up upgrade. I like the king arms hop ups, but having already upgraded another sniper, (L96, bolt action) I strongly feel a hop up is the primary upgrade. I currently use a Prometheus hard type in my L96, not sure what degree of hardness, but I'm not sure what type of rubber is optimal for a semi auto gun vs a bolt action. I intend to upgrade it to around 460 - 475 fps. Enlightment, anyone? I'm also open to other ideas for any your personal tried and true upgrades. Dmr only, please. I'm also planning to do the usuall. (better piston, if needed, bearing spring guide, if needed, probly a Promy tb barrel, concave hop up spacer, etc)

[Off_kilter]

Prommy barrel and R-hop!

[airsoftjunky]

I read about the R-hop up, but details of it I know none. Where do I purchase, and what makes it outstanding?

[ThunderCactus]

More importantly, what weight of ammo do you plan on using?
If you're using anything but .36s at 475 there's no point upgrading your hop rubber

[Stealth]

This topic has been discussed to death:

http://www.airsoftcanada.com/showthread.php?t=146831

http://www.airsoftcanada.com/showthread.php?t=145810

http://www.airsoftcanada.com/showthread.php?t=143354

Although, reading them now I guess I should add that I find myself using Lonex hop units and R-Hops more often now. Mostly because back in July I never used the Lonex units and I didn't have a ton of time to fiddle with R-Hops.

I've also started my migration to .32g BBs.

[sushicake]

I wouldn't remove the full auto function, I'd keep it as a precaution. If you rip on semi too much in too short a time frame (shooting again before the gears fully cycle) it will cause the gearbox to seize. And its either crack open the gearbox to reset everything or just shoot a burst in full auto to reset it.

A lot of companies keep their full auto functions on dmr based guns. Take the SR-25 for example there's a nub on the body that looks like it'll stop the selector from going into full auto, but in actual fact the selector will go right over that nub and go into full auto no problem. Again this is for primarily resetting the gearbox, but if the owner wants they can still put it into full auto.

[ThunderCactus]

The reason you remove full auto is because most fields prohibit even the possibility of full auto above a certain limit.
Example:
Full auto: 420fps
Semi auto locked: 440fps
Bolt action: 490fps

And full auto is useless on a dmr since you never use it and it's inherently less accurate than semi auto.
Dmrs are generally set up to cycle fast anyway with 11.1v lipos or 9.6v large batts. It's typically extremely difficult to mechanically jam a dmr or really any well set up aeg on semi.
Sw-comps drastically reduce the chance of mechanically jamming as well through application of active motor braking.

[airsoftjunky]

Originally Posted by ThunderCactus

More importantly, what weight of ammo do you plan on using?
If you're using anything but .36s at 475 there's no point upgrading your hop rubber

I usually use .30's. Would be willin to try .32's or .36's though...

[ThunderCactus]

if you're using .3s, stick to 430fps, anything above that is just losing accuracy
I run my VSR at 430 with .3s and I get pretty spectacular range and accuracy though

[airsoftjunky]

Good to know! Ok so would someone please explain R hop to me? I find almost no actuall info about it anywhere. But everyone keeps talking about it. Do you buy it? Make it? How does it work?

[Stealth]

https://sites.google.com/site/hsarmo...s-and-services
Scroll down.

Order direct from HS5 or through us.
It's really not for newbie tuners, although you're more than welcome to attempt it. To get somewhat good results you'll need the Rhop tuning/install tool or some kind of similar home-brew.

[Azathoth]

Originally Posted by Stealth

https://sites.google.com/site/hsarmo...s-and-services
Scroll down.

Order direct from HS5 or through us.
It's really not for newbie tuners, although you're more than welcome to attempt it. To get somewhat good results you'll need the Rhop tuning/install tool or some kind of similar home-brew.

Definitely not for newbies. I've almost been taken out of retirement by people trying RHop installs themselves that had no tuning experience. 99% of problems is too much downward force on the hopup resulting in stripped pistons.

And in all honesty my first self R-Hop install took me nearly 6 hours of fine sanding and testing. I tried the dremel as a short cut and that was a big waste of time.

[airsoftjunky]

Great info here. Thanks. One question I have, is does the bb rub directly on the R hop? Or does it push through the rubber? Just wondering, because if I'm gonna be superglue-ing the rubber to the R hop, I hope it works the first time, because if not its going to be super glued on there! But if not glued, its going to fall through into the barrel wont it? Any info here would be appreciated. I will, however, research this more later when I have time.

[MaciekA]

Direct contact. You need a moundless bucking to use with it.

[airsoftjunky]

Originally Posted by MaciekA

Direct contact. You need a moundless bucking to use with it.

Ok! After further research it is now crystal clear, except for one thing. Do I need a special nub to make this adjustable? Or do I use the original nub to any success? Or do I sand the R hop to a certain weight of bb? (I'm not sure yet exactly what weight of bb I plan on using, or what fps for sure I wanna run.) I'v seen some talk about an M nub. Is this mandatory to the true success of the R hop?
Edit: I just cheched the faq's on Hs5's site, and it looks like either works, or some people make their own nub. However, if anyone has personal experience with either, I'm all ears.