Firefly hopup bucking or KM combo?

[fal]

I'm planning to replace my hopups to get better trajectory and bit more range I suppose. And I was wondering whether I should go with Firefly hopup bucking(if I can find) or KM RH65 V notch hopup + KM TN barrel combo? I heard KM hopup only works best when it is used with their TN barrel setup. Both will be installed in either stock TM 2 piece hopup unit, or guarder upper piece hopup unit.(not one piece)

 

What I'm wondering is, the FPS lose, range increasement and trajectory stability improvment, when either of these are installed over stock TM hopup rubber + Systema BS tightbore setup. What I want to find out after all, is whether these upgrade would be actualy worth it.

 

I heard someone lost 50FPS due to KM hopup rubber, but I have yet to confirm which barrel is used in this setup. 10 to 15fps lose can be neglected, but 50 is just hugh.

 

If anyone have this kind of setup or have 1st hand exprience, please post your comments. And no guess work or "I heard" please. I'm trying to get real information.

 

Thanks.

[Sale]

I have a KM rubber with a Prometheus barrel in my gun and it shoots well. I've heard that it's KM barrels that don't work well with other than KM rubbers, not the other way around. Any loss in FPS is caused by poor fit or something. It's not a feature so regardless of the hop up sleeve type, you should get equal muzzle velocity or swap/modify parts for the best air seal.

 

A team mate of mine just installed a Big Out H-hop and a KM RH65 hop up sleeve in his gun and it's tremendously accurate according to him. He has done a lot of tests in this field so I trust his word on this. I have never even seen a Firefly hop packing so I can't say which is better, but the KM hop packing is definitely an improvement over normal ones.

 

-Sale

[fal]

Ah I see. So it's the barrel, not the rubber then?

 

50fps loss that I heard, was that he lost 50fps when he put RH65 hopup in, but when he swaped it back to stock TM one, the loss was gone completely. He was saying that the reason must to do with RH65 hopup rubber because of this. This one was fitted to CA M15A4.

 

I have read another airsofter who also exprienced FPS lose(about 50FPS also) and it was installed in moded M4 with guarder one piece hopup unit. I believe neither have used Prometheus tightbore, but some other brand's tightbore. I can vaguly remember that moded M4 had systema barrel in it.

 

I read by someone who actualy had firefly hopup setp and he said it improved the range quite a lot. His friend had KM combo(RH65 + TN) and the range was increased to 210feet +. The gun was shooting at 300FPS. But he was unsure what spring it had and because of this, he couldn't estimate the fps lose. But he also noted that it seemed to have M100 spring, which means that is also about 50FPS decreasement in FPS. Again, I couldn't find which chamber this gun was fitted with.

 

What I think is that it has to do with more of combination which barrel and chamber you are using.

 

If you don't mind me asking, which hopup chamber are you using and which gun? and also your team mate's? Also I belive you and your friend didn't exprience any FPS loss? If you don't use Big Out H-hop, how much difference was there between your setup and your friend's?(in terms of accuracy and range)

 

Thanks.

[trfo2o]

I have a KM rubber with a Prometheus barrel in my gun and it shoots well. I've heard that it's KM barrels that don't work well with other than KM rubbers, not the other way around. Any loss in FPS is caused by poor fit or something. It's not a feature so regardless of the hop up sleeve type, you should get equal muzzle velocity or swap/modify parts for the best air seal.

 

A team mate of mine just installed a Big Out H-hop and a KM RH65 hop up sleeve in his gun and it's tremendously accurate according to him. He has done a lot of tests in this field so I trust his word on this. I have never even seen a Firefly hop packing so I can't say which is better, but the KM hop packing is definitely an improvement over  normal ones.

 

-Sale

<{POST_SNAPBACK}>

 

Ya i'm gonna have to call BS on what you said about KM barrels working well with only a KM bucking. I had the KM barrel i'm using now in my CAm15a4 and before I used it in my old SG552(which is no longer mine) with stock hop up. With the SG552 I got the best results i've ever seen with an AEG. barrel was 363mm using .25 excels or AE. With the CA it works really well now that I have a prometheus soft type bucking and a big out h hop up nub. I can now hit man size targets at 200' after about 2-3 shots. Before the CAm15 sucked with only a guarder soft type bucking and KM barrel. It was impossible to find a good hitting accuracy point.

 

 

Ah I see. So it's the barrel, not the rubber then?

 

50fps loss that I heard, was that he lost 50fps when he put RH65 hopup in, but when he swaped it back to stock TM one, the loss was gone completely. He was saying that the reason must to do with RH65 hopup rubber because of this. This one was fitted to CA M15A4.

 

I have read another airsofter who also exprienced FPS lose(about 50FPS also) and it was installed in moded M4 with guarder one piece hopup unit. I believe neither have used Prometheus tightbore, but some other brand's tightbore. I can vaguly remember that moded M4 had systema barrel in it.

 

I read by someone who actualy had firefly hopup setp and he said it improved the range quite a lot. His friend had KM combo(RH65 + TN) and the range was increased to 210feet +. The gun was shooting at 300FPS. But he was unsure what spring it had and because of this, he couldn't estimate the fps lose. But he also noted that it seemed to have M100 spring, which means that is also about 50FPS decreasement in FPS. Again, I couldn't find which chamber this gun was fitted with.

 

What I think is that it has to do with more of combination which barrel and chamber you are using.

 

If you don't mind me asking, which hopup chamber are you using and which gun? and also your team mate's? Also I belive you and your friend didn't exprience any FPS loss? If you don't use Big Out H-hop, how much difference was there between your setup and your friend's?(in terms of accuracy and range)

 

Thanks.

<{POST_SNAPBACK}>

 

Ya bs about that guy's friend. 210' with only 300 fps. I'm the guy who lost 50 fps in my CA. When I switched back to the guarder bucking my FPS was back to

normal. I had AEX look at it after I couldn't figure out what to do, and they tried and tried and couldn't get it to get back up to normal my springs normal fps level.

The best combination IMO is big out BOS hop up nubs, prometheus soft type bucking, 1 piece metal hop up, and a KM or prometheus barrel. This combo gave me really nice results.

[fal]

Thanks for coming in. Now we can debate based on two different results upon actual experiences.

 

I think Sale is not guranteeing his word on KM combo idea, as he said "he heard" and he is using his KM hop with Prometheus tightbore. I belive he didn't exprience any FPS loss, but he is yet to provide information/numbers on improvement in range and accuracy, also full list of his components on his setup. So I'm waiting to hear those.

 

Also the fact I'm thinking of, it could be combination between hopup chamber, barrel and the rubber. It might give better result if stock TM hopup unit is used with KM rubber and TN/Prometheus barrel instead of stock CA hopup unit. Then again, this is only a speculation untill, proper evidences are provided.

 

How does your setup performs in terms of trajectory stability? and what spring does your M15A4 in it?(in case you "cant" say FPS of your gun.)

 

For 300fps -> 210ft report, I believe you can achieve such range, because I have seen a custom gas gun shoots only 200fps or even less(cant even penetrate a cardboard at pointblank) and had KM RH65 + systema tightbore + modified TM hopup unit in it, and it was reaching out to 120ft. That doesn't mean it is accurate though. TM MK23 spring pistol has 220fps approx, and I have seen it reaching out to 130ft. And this is just stock TM springer hopup. Not some special setup like KM combo, Firefly or Big Out h-hop.

 

Have you tried using Big out H-hop with stock TM hopup? Just wondering how it would be like compare to Prometheus hop up rubber.

 

This FPS diminishment with KM hopup rubber is really weired. Because in theory, it cannot just lose fps unless fitting is not properly done, or hopup chamber is inferior to the tolerance that it will have problem with airseal. I really would like to hear the result of KM combo with other hopup units such as stock TM ones or Guarder 2 piece/1 piece or Systema ones.

 

I suspect that in your case, it must have been the airsealing between KM hopup rubber and CA one piece hopup unit. Because you said by switching to Guarder hopup rubber, they worked fine. As far as I know, and to my exprience, Guarder hopup rubber is thicker than others. I almost broke my stock TM M4 hopup unit when I tried to pull it back out. This wasn't the case with stock TM rubber. CA one piece hopup unit might have bigger bore where barrel goes in, compare to other hopup units. But this is just my speculation again, because I have yet to have exprience with hopup units other than stock TM ones. Airsealing is really sensitive matter so even slight tolerance difference/inaccuracy can cause problem.

 

Thanks.

[Five-sEvEn]

I read by someone who actualy had firefly hopup setp and he said it improved the range quite a lot. His friend had KM combo(RH65 + TN) and the range was increased to 210feet +. The gun was shooting at 300FPS. But he was unsure what spring it had and because of this, he couldn't estimate the fps lose. But he also noted that it seemed to have M100 spring, which means that is also about 50FPS decreasement in FPS. Again, I couldn't find which chamber this gun was fitted with.

<{POST_SNAPBACK}>

I made the post. It was stuck in an MP5K with an M4 length barrel and a full cylinder. And doing a quick lookup at what the RH65 is, that's not the rubber he had in this gun. His was a full length hopup rubber. Oh ****. I just found the hopup rubber he had on his gun via the website that told me what the RH65 was. He was using a Soft prometheus hopup bucking in conjunction with the KM barrel. Sorry about the mixup. I guess my opinion on the KM rubber is now null and void .

 

 

Ya bs about that guy's friend.  210' with only 300 fps.

<{POST_SNAPBACK}>

It was Zero-ops tuned. Killer studios was its predecessor I believe. I believe my friend easily. If I can get almost 190' with 295fps, with an MP5K length barrel, 210' doesn't seem out of reach if you know how to tune properly. Also, he shot on a measured field and it clearly outranged his 210' Beta shooting around 330 I believe.

 

Now we can debate based on two different results upon actual experiences.

<{POST_SNAPBACK}>

Someone needs to get both, and do some actual test results. Once I find some cash, I plan on doing it for myself though

 

For 300fps -> 210ft report, I believe you can achieve such range, because I have seen a custom gas gun shoots only 200fps or even less(cant even penetrate a cardboard at pointblank) and had KM RH65 + systema tightbore + modified TM hopup unit in it, and it was reaching out to 120ft. That doesn't mean it is accurate though. TM MK23 spring pistol has 220fps approx, and I have seen it reaching out to 130ft. And this is just stock TM springer hopup. Not some special setup like KM combo, Firefly or Big Out h-hop.

 

Have you tried using Big out H-hop with stock TM hopup? Just wondering how it would be like compare to Prometheus hop up rubber.

<{POST_SNAPBACK}>

With the 210'+ range reported by my friend, he made no mention as to how accurate it was at that range, just said it reached out that far straight. If you think about it, fussing around with my friends stock G-Spec today, seeing as that shoots past 200' easily, it shouldn't be supprising that an AEG can't do that same with the right tuning.

 

Also, the big out h-hop works well with the stock TM rubber. I have no other normal rubbers to compare it too so I can't say much, but it does improve trajectory if anyone was wondering .

[Sale]

Someone needs to get both, and do some actual test results. Once I find some cash, I plan on doing it for myself though

It's not just about the cash... I've had different rubbers and tightbore barrels lying around for months but tests like this demand a huge amount of time and effort. Even if the gun is quick to disassemble. The reason why just installing the parts in different guns doesn't work is because they are individual platforms. You should change as little as possible parts when you test a single part's effect like the H-hop.

 

My mate chronoed the gun now and it's shooting really low for an M100. I'll ask about the barrel he's using to see if it's something else than a KM. Maybe there is some truth that you should have a KM tightbore for their hop up sleeves. The hop up chambers on both our guns are Systema and they are assembled into Guarder receivers. My gun is in pieces at the moment so I can't provide test data.

 

-Sale

[Five-sEvEn]

It's not just about the cash... I've had different rubbers and tightbore barrels lying around for months but tests like this demand a huge amount of time and effort. Even if the gun is quick to disassemble. The reason why just installing the parts in different guns doesn't work is because they are individual platforms. You should change as little as possible parts when you test a single part's effect like the H-hop.

<{POST_SNAPBACK}>

 

He speaks the truth!

 

It took me a couple hours to fully test both the H-hop nubs in my K and AK (even though I read the website). While the white nub is meant for longer barrels, and black is meant for shorter barrels, I found that the white nub performed better in both my guns than the black one. The configuration of my guns isn't very typical, so I guess the results from certain products aren't very typical in my guns as well...

 

I want to become an expert tuner someday, so carrying out tests and finding the time to do so is just another part of my hobby

[cjfield1129]

Wow, good debate so far! I too have not had any luck at all with KM RH buckings (RH65 to be specific). I have tried one in both my stock barrel and a KM tigthbore barrel. I have a G36 with stock hop up unit. The bucking was changed to the RH65 during a barrel upgrade (KM TN tightbore barrel). I thought the barrel may be defected and tried to switch back but the problem stayed the same. I experienced an approx 50 fps loss with this combination setup in both barrels. I also experienced feeding problems as it seemed like the lips of the bucking were a little too stiff causing the bb to not feed properly. You don't want the BBs to roll out but you also don't want it to be so tight that you can't blow the BBs out with a breath of air from your mouth. I tried and tried with numerous re-installation attempts but didn't have any luck. The fps went back up and feeding was corrected after I installed a Guarder clear bucking. In all actuality, even the guarder bucking didn't have the best airseal until I played around with it for a bit. I had to install the brass ring a further into the hop up unit. I have a Systema bucking that I will try if this setup ever goes south again on me. I don't want to touch anything right now as I have a very airtight setup right now. I have minimal experience with Prometheus buckings so I won't speculate. I only installed a soft (purple) bucking into a stock TM and had good results and left it like that.

[Mech_E_Travis]

If you lose power with a KM bucking, try 3-4 wraps of teflon tape around the forward edge. I did this and picked up 47 fps in my ca m15.

[cjfield1129]

Interesting fix...Are you wrapping the barrel or the bucking? If your talking about the bucking, how do you get it to fit into the hop up unit then? Also, what barrel are you using?

[Sale]

3-4 layers of teflon tape doesn't do much to the outer diameter so it might still fit without problems, while providing a good seal.

 

-Sale

[trfo2o]

If you lose power with a KM bucking, try 3-4 wraps of teflon tape around the forward edge. I did this and picked up 47 fps in my ca m15.

<{POST_SNAPBACK}>

 

hmm never tried that.

 

Well this is what i'm gonna say since I DO own both a RH65 new type KM bucking and now a owner of a prometheus soft type.

I can't say what kind of spring I have in my gun, but it's where mostly every American has their gun at (field limits that is).

 

If you compare the size of a KM bucking and a prometheus/guarder/CA, the KM is really short. Now the end of the bucking that faces the air nozzle is like non existent, it doesn't go out as far as a normal bucking. Therefore I think when the airnozzle chambers a round the airnozzle is not fully sealed inside the bucking, causeing a little bit of an airleak when fired. I tried for many hours to by bucking to work and I failed to get it to be accurate and give good air seal. AEX found they couldn't either.

Oh ya my set up is

guarder 1 piece metal hop up

systema air nozzle and TM nozzle (i've tried both and they both had the same results)

363mm KM inner barrel

.25s (AE, excel, toytec)

 

I've tried the following set ups. (all with the KM barrel)

1.guarder 1 piece with guarder %50 bucking

2.guarder 1 piece with guarer %70 bucking

3.CA 1 piece with the ^ set ups.

4. guarder 1 piece with KM bucking (RH65 new type)

5.Guarder 1 piece with Big out H nubs and a guarder %70 bucking

6. Guarder 1 piece with Big out H nubs and prometheus soft type bucking

 

#1 it was ok but I couldn't adjust it to where the bb's had a flat trajectory for 200' or so. When I tried they would over hop or maybe drop off to the left the right. But overall it wasn't too bad of a set up.

#2 Don't try it, it gave me even worse results then ^

#3 only worked well with the guarder %50 but was inconsitant

#4 Like I said before, bad accuracy and 50 fps loss

#5 Now this set up was really great for long long range like out to 250' but closer ranges it was pretty inconsitant. Why this is I don't know. I adjusted it higher because I wanted to see what kind of range I could get out of it. So I adjusted the hop to a little higher then usually and all I can say is that it was pretty spot on accurate at long ranges.

#6 I haven't tested much of this, i've only put 1 mag through to test (68 rnds) So far though with toytec .25's it's really really good, best set up so far. Flat trajectory. I tested it at my 200' range and it past the test in terms of accuracy. I need to try even longer ranges when I get the bb's but i'll keep this thread in formed.

 

I'm also going to try and buy a prometheus inner barrel to test.

 

and yes the white H nub is the best over all because it's softer and has a different shape.

 

Now that's what I have to say. I'm not a liar and I have honestly tried and tested all the above set ups many many times in a row to find that kind of accuracy my older SG552 had.

[fal]

Very intersting. Nice discussion here guys. Keep 'em coming!!

 

It seems KM RH65 is a bit off from standard dimension. The thickness of rubber is thin enough to develop the air leak. The length of it is also shorter which is another factor causes airsealing problem. It's not dependent on barrel either because from this discussion, various barrels has been introduced such as KM TN, Prometheus and Systema BS. But problems are still there.

 

cjfield1129 reported that his KM combo setup with G36 hopup unit causes misfeeding. But this is first time I ever heard of such instance. Misfeeding indeed relates to other factors such as nozzle and barrel/hopup fitment to the hopup unit. It is yet to be verified that whether this is caused by RH65 or not.

 

Mech_E_Travis reported that few wraps of teflon tapes cured FPS loss, which seems that most of air leaking occuring towards the front rather than inbetween nozzle and the hopup rubber. We need more people to expriement on this so we are sure this can be the cure.

 

If hopup rubber is not properly sealed with nozzle before firing, this can affect shot accuracy and consistancy greatly. I personaly have heard few instances that RH65 has airsealing problem, but it is first time I ever heard that it's also causing shot accuracy problem.

 

Overall, It seems that Prometheus hopup rubber, has good results. But I have read one instance that it doesn't work well with Systema one piece hopup unit.

 

Big-Out H hop seems that it stabilizes the trajectory and increases the range when it is used with Prometheus hopups. I have read quite a few instances that this combination works. Also regarding to Sale, that RH65+Big-out H hop, also improves accuracy and range, even though it may have air leak issues. What I'm wondering here, is comparing these two setups when RH65 is properly tuned.

 

Though, if Prometheus hopup rubber + Big-Out H-hop combo gives same or better improvement on accuracy and range increasement over KM RH65 with Big-Out H-hop setup, I see little to no point of bothering RH65 issues. But this comprasion hasn't been made yet, so it would be interesting to find out which combination works better.

 

My speculation is that aftermarket hopup rubbers such as Prometheus and KM ones are made to work with stock TM hopup unit. I'm guessing this because they don't make their own hopup units and my logic is that when they made these parts, they would run tests on stock TM hopup units. So eventualy, these hopup rubbers would work best with TM stock hopup units raher than others such as Guarder, CA or Systema. It would be good if we can pull some more results of these setups when they are properly installed on stock TM hopup units.

 

Regarding to trfo2o, that Guarder hopup units + RH65 cause not only bad airsealing, but also accuracy issues. Others have exprienced airseal problem but not the accuracy problem. It maybe the case tha Guarder hopup doesn't work well with KM RH65 hopup rubber.

[trfo2o]

personally I would just stay away from the Km bucking. Buy a prometheus or guarder bucking. The prometheus works the best in my guarder 1 piece metal hop up now. It could be better I bet if I bought a prometheus barrel.

 

Where did you hear that systema 1 piece metal hop ups don't work well with prometheus buckings?

[fal]

I read it somewhere in this forum. I cannot recall who it was but he said he had Systema 1piece metal hopup unit and installed Prometheus hop rubber but it didn't work well. So he switched it back to Guarder clear bucking.

[trfo2o]

hmm do you mind finding it? A guy in the armalite photo threads has that set up and he didn't mention anything wrong.

[fal]

ok I will try. But please allow me some time because it is hidden somewhere. I found it while I was reading countless threads. He didn't say much by the way. What I said was pretty much all he did.

 

It is known, so far, to be that Premetheus Soft hopup rubber + Big-Out H-Hop gives 200ft~210ft range, however the accuracy is unknown. It seems that at 300FPS and upwards of muzzle velocity, BB can easily reach out to such distance.

 

I'm still keen to find out "numbers" with properly tuned/installed KM RH65 + Big-Out H-hop setup. Like at such range you can hit man sized target or a torso size target etc. Also we need to know what FPS the gun was shooting at.

[trfo2o]

Ok I contacted the guy who has systema 1 piece metal hop up, prometheus soft type bucking, prometheus inner barrel, and big out H hop up nubs. he should be responding anytime now.

 

as far as having 300 fps and being able to reach out to 200 ft. I'd say the only way to do that is setting the hop too high and haveing the bbs curve up after taking a shot. Even with 300 fps your going to have a hard time hitting anyone moving away at 200'.

[trfo2o]

This is a quote from thichrome

 

"I'm really not that knowledgable on the accuracy side; I use what everybody has told me is the best set-up and I take it at face value that there's nothing better.

 

I can hit a man sized target (even a crouching man sized target) at around 180 feet max range on my Mk.12 Mod.0 SPR at 400 FPS with .25's (field limit in the northeast USA).

 

For the Big-Out hop-up nubs I've tried both the black and white and a regular and I've noticed no difference between them; but I do plan on doing some testing when I have the time and see if I keep records that one will seem better than the rest.

 

for now, the best setup seems to be a Systema Hop-up (I haven't tried Guarder like you have before). and the single best part I've invested in is the First Factory Strike Chamber. This makes you able to dial in the hop-up much finer than the traditional system.

 

 

If you're based in the UK, and can only have a gun that shoots 330 FPS, I would highly suggest getting a Tanio Koba twist barrel."

[cjfield1129]

OK, just another update from my tinkering today. I could not get my new KM RH65 to provide quality airseal at all. I tried it in a Madbull TB barrel and two separate stock barrels (Star and CA). All three experienced a pathetic drop in FPS not to mention feeding issues. I tried several layers of teflon tape as suggested earlier -still no avail. I also tried a Systema bucking in each of the barrels. Better than the KM, but still not as good as it should be. My fps was still the highest with the guarder clear bucking. Unfortunately that tore; hence the new tests. I have a Prometheus soft, a Guarder clear, and a Guarder black (improved??) buckings on order. I'm hoping I'll have luck with the Prometheus bucking. I'll post back with the results.

[tgrillo]

Where can I get a Big Out H nub? Everywhere seems to be out of stock. +1 to whoever can find one for me.

 

Also, should I spend the $40 and get a STRIKE chamber for my G&P M4's hopup? Right now I'm running a G&P Hopup, Prometheus Soft Bucking, and Prometheus Tightbore. I am hoping to install a Big Out H Hop into the prometheus bucking, but I'm also curious about the STRIKE Chamber.

 

Thanks

[fal]

Thanks for input guys.

 

It seems Prometheus soft bucking have good reputation overall. However, with guarder buckings, I heard some issues such as over hoping, and it being too soft that it rips easy. But someothers reported it is good. Guarder bucking falls into kinda mixed feedback.

 

So it looks like teflon tape cant cure the problem with RH65. Where did you wrap your teflon around? Did you wrap it at the end of hopup sleeve where it overlaps with the barrel? What hopup unit did you use? I don't know for sure, but if stock TM hopup is used, it might work, since I assume that KM doesn't make their own hopup unit, and is designed to work with TM hopup unit.

 

From what I have heard from one of the experts, those one piece hopup units(in case of M16 varients) is not recommanded over stock TM 2 piece hopup, because of the tolerance issue. I didn't have chance to have chat with him further on this issue but that might mean something.

 

I think best setup for hopup system, would be go with same manufacturer. This is just a logic work, but for instance, Prometheus produces their own tightbore, hopup unit and hopup sleeve. wouldn't it be that they are designed to work together? For instance, I heard systema is gone down the hill recently, but that is when you mix and match parts from different brands. I read that if you have all systema internals, they will work together nicely.

 

It seems getting the best hopup configuration, is making good combination between barrel, hopup sleeve, hopup unit and the nozzle. It looks like you can only obtain optimum results when these components are matched and without a doubt installed properly.

 

I havn't heard good things about G&P hopup. So far I have read people recommanding either Systema or Strike chamber but never heard of anyone recommanding G&P hopup unit.

[ronburgundy__]

Where did you find a prometheous hopup unit?

[tgrillo]

who has the H hop nubs in stock....I really need another one.