Madbull Shark bucking. PDI W-hold bucking. Must share my success

[airsoftjunky]

So in my long recent journey to a good air seal, I've played around with different hop up buckings and felt the need to share my success. I started with a King Arms Bw15. The stock bucking ripped after only 1000 rounds or so, and thus began my journey. After trying several different cheaper buckings, I decided to try some of these other cool ones that have been hitting the market.
The first one I tried was a pdi w-hold.

http://www.airsoftstore.ca/index.php...roducts_id=164

It's a very nice bucking. However, I was having troubles with air seal. I thought my low fps was from the need of a higher power spring, so I put in a Lonex M130. I was achieving approx. 370 fps. I emailed Airsoft Store Canada and asked for advice, and they suggested wrapping a few wraps of Teflon tape around the bucking. I did so, and achieved approx. 423-425 fps. Much better. I took it out that evening and did some test shooting. It worked very well with .25 bbs. At 100 feet, (all the room I had) the grouping was about 5 inches. I then tried .28 bbs, which is the weight I prefer for that fps, and the grouping went wild. I'm assuming the rubber does not work to well when you have to dial it up that much. I was content for now, however I would probably recommend this rubber for fps limits of maybe 400 fps max, but I'd like to hear any input on that from anyone else.

Two days later the Madbull Shark Bucking arrived.

http://shop.ehobbyasia.com/upgrade-p...cking-red.html

So far I have nothing but good to say about it. I just installed it tonight, and was happy to see that it fit just snug enough as to create a perfect air seal in my hop up chamber, without teflon tape. Then, on to the chrono. Much to my surprise, the fps jumped up to 430-435! I have yet to see how it performs long range. The soft rubber may be to soft for that high fps, but as soon as I get a chance to make a drive to the country and do some accuracy tests I will make a point up updating this.

I do not want to give the pdi w-hold a bad review. It is perhaps just not the right fit for the King Arms hop up unit, but as of this moment I will recommend the Madbull any day of the week. I hope this can help someone with an air seal problem such as I had, and if anyone has anything to add to this I'd be very interested. Any long term results anyone?

[airsoftjunky]

So, just came back from some tests, and I can say its definitely not shooting worse. I didn't have the privilege of having an actual distance to compare with, but with the MadBull bucking I am now able to use .28 bbs more effectively, and at the longest distance a had available (I can only guess approx 180 feet) I can easily hit a pie plate size target quite frequently.

Two things of interest to note:

First, I tried it with my Promy barrel. The hop up window was to narrow to fit the fishbone or concave spacer that came with the bucking. The MadBull barrel worked, however. I tried the Promy barrel with a regular nub and the MadBull bucking, and it definitely yielded no special results.

-Second, it doesn't seem to work to good with .30 bbs. As with the PDI rubber, it seems to soft to accurately lift the heavier bbs. Here again, however, this could be just my own opinion. Now begins the long term results. I assume the accuracy will just continue to improve as the rubber wears to the shape of the spacer.

[LocoYokoPoco]

I too, was pointed towards the PDI W-Hold bucking and had a very similar experience. It does't work well at all for higher fps (350+ ish) setups. In the end, I stuck with my Prometheus purple rubber + SCS Nub, works muchos better in my DMR setup.

[pestobanana]

I've had quite positive experiences with PDI W-hold rubbers in 3 different guns shooting at 370, 380 and 450 fps. I find Prometheus purple just as good, but right now I'm using bridge tensioners and I find that best.

Originally Posted by LocoYokoPoco

I too, was pointed towards the PDI W-Hold bucking and had a very similar experience. It does't work well at all for higher fps (350+ ish) setups. In the end, I stuck with my Prometheus purple rubber + SCS Nub, works muchos better in my DMR setup.

[airsoftjunky]

Originally Posted by pestobanana

I've had quite positive experiences with PDI W-hold rubbers in 3 different guns shooting at 370, 380 and 450 fps. I find Prometheus purple just as good, but right now I'm using bridge tensioners and I find that best.

Just curious what brand and style of hop up unit you had the good luck with? Also, do you use the bridge tensioners with the promy purple rubber? I'v been interested in trying those.

[pestobanana]

Originally Posted by airsoftjunky

Just curious what brand and style of hop up unit you had the good luck with? Also, do you use the bridge tensioners with the promy purple rubber? I'v been interested in trying those.

I've used Lonex, CA, G&G and VFC hop up units. I find the unit itself makes no difference, as long as you tune them all. I have had no FPS changes from switching hop up units, and no accuracy benefits from changing out a plastic unit to a metal one.

I use a Modify moundless hop up rubber, and a Prometheus bridge tensioner.

[Rabbit]

Originally Posted by pestobanana

I've used Lonex, CA, G&G and VFC hop up units. I find the unit itself makes no difference, as long as you tune them all. I have had no FPS changes from switching hop up units, and no accuracy benefits from changing out a plastic unit to a metal one.

I use a Modify moundless hop up rubber, and a Prometheus bridge tensioner.

There probably isn't a hop up combination I HAVENT tried these days (with the exception of bridge/rhops) and I can tell you, you DO get various results by changing out units - they all dont have the same dimensions and they all dont seal the same either.

You also have to take into consideration nozzle to hop up seal as well which is one of the main causes of air leaks - this is why I always try and match nozzle and hop up unit brands.

When it comes to hop up sleeves, the rule of thumb is soft sleeves for 400fps and less - Hard sleeves for anything over 400. (Some will actually say soft 350fps and lower and hard for 350fps and above.)

I've had nothing but horrible results in air seal with the PDI-W hold in various units - teflon tape is a MUST.

The most consistent results in fps have ALWAYS come from using a Prometheus Purple and ARS for me.

The best combination I have ever used for a consistent 395fps have been a combination of a Cyma Nozzle, Cyma unit and a Prometheus Purple sleeve and purple nub - its just a shame the Cyma m4 unit does not fit in all guns (does not work with my King Arms m4 receiver currently)

Currently I am using the Prometheus Neo chamber, prometheus purple sleeve and nub at a very consistent 363fps.

Edit: If you are curious about range - hands down the best range I have ever had was from the ICS hop up unit using a stock 247mm barrel (ICS CXP) easily over 200 feet with stock sleeve and stock nub.

Barrel length/bore will get you accuracy but will do nothing for range which is the conclusion I have come to - hop up unit/arm engagement is KEY.

If you look at the Lonex hop up adjustment arm, it is MUCH different than most standard arms - also wider (I can't even get this unit to mesh with various receivers and nozzles - always seems to air leak yielding much lower fps compared to another unit in the same AEG)

In conclusion there are MANY variables when it comes to selecting a consistent match for hop up units and everything else used in conjuction.

[airsoftjunky]

The madbull bucking I just reviewed is a 60 degree bucking. Unfortunately I don't think they make a harder one. even though I had good success with it, is it to soft for 430 fps? Is it going to wear out quite fast?

[Rabbit]

Mad Bull makes two kinds of sleeves, the red and blue - they are both 60 degree which is fairly soft - and yes, at higher fps they will wear down much quicker an/or tear.

You can find them both at airsoftparts.ca and read about them in the small description - the blue actually states its supposed to be used for 350fps and lower.

During my several year long quest in hop up unit selection, i've actually read that those mad bulls cause jams and double feeding all over the place - mind you this boils down to your own user perspective and results will always vary.

Edit: My suggestion for 400fps and above - pair this bad boy with some teflon tape (if needed) and you're golden.
http://www.airsoftstore.ca/index.php...626jhvmv2l9cq7

The best investment I have ever made in airsoft is buying my own chrono because i do my own gun work. I can check things twice, thrice whatever you want.

I ALWAYS tear down my hop up units twice - once without teflon tape, once with. Sometimes it will fit sometimes it wont, not all inner barrels have the same diameter (such as the mad bull python) and some hop up sleeves are thicker than others - therefore not allowing the teflon tape and/or creating air leak.

[airsoftjunky]

Originally Posted by Rabbit

Mad Bull makes two kinds of sleeves, the red and blue - they are both 60 degree which is fairly soft - and yes, at higher fps they will wear down much quicker an/or tear.

You can find them both at airsoftparts.ca and read about them in the small description - the blue actually states its supposed to be used for 350fps and lower.

During my several year long quest in hop up unit selection, i've actually read that those mad bulls cause jams and double feeding all over the place - mind you this boils down to your own user perspective and results will always vary.

Edit: My suggestion for 400fps and above - pair this bad boy with some teflon tape (if needed) and you're golden.
http://www.airsoftstore.ca/index.php...626jhvmv2l9cq7

The best investment I have ever made in airsoft is buying my own chrono because i do my own gun work. I can check things twice, thrice whatever you want.

I ALWAYS tear down my hop up units twice - once without teflon tape, once with. Sometimes it will fit sometimes it wont, not all inner barrels have the same diameter (such as the mad bull python) and some hop up sleeves are thicker than others - therefore not allowing the teflon tape and/or creating air leak.

Interesting, because I installed one of those madbulls in my girl friends gun and she had two jams early in the game before they finally stopped jamming. I guess we'll see how it works at the next game. It's a 370 fps set up vs a 430 fps, however.

[airsoftjunky]

Originally Posted by pestobanana

I've used Lonex, CA, G&G and VFC hop up units. I find the unit itself makes no difference, as long as you tune them all. I have had no FPS changes from switching hop up units, and no accuracy benefits from changing out a plastic unit to a metal one.

I use a Modify moundless hop up rubber, and a Prometheus bridge tensioner.

One thing I don't understand about the bridge tensioners, is they're to long to fit in most if not all barrel windows. Is trimming from both ends required to utilize them? Or are they designed to hang up on both ands of the barrel window then just push through more in the middle, if you will. I hope that made sense. :S

[Rusty Lugnuts]

I've had good results with the reaps bucking, not infinity of course, but good seal and consistency- which is all i ask of a bucking

[pestobanana]

Originally Posted by Rabbit

you DO get various results by changing out units - they all dont have the same dimensions and they all dont seal the same either.

Originally Posted by Rabbit

I've had nothing but horrible results in air seal with the PDI-W hold in various units - teflon tape is a MUST.

I would disagree to both, I've used all those different hop up units and seen no real difference. Yes Lonex units are made to different specs, but after modding it to fit it works fine.

As for the PDI W-Hold leaking, I've never had a leak with it, and I've never had to use teflon tape. Right now I have it in a M14, shooting a consistent 380 fps with a M100 spring. It also worked fine in my G36 and another M14, which was netting 455 FPS on a M120 spring.

Originally Posted by airsoftjunky

One thing I don't understand about the bridge tensioners, is they're to long to fit in most if not all barrel windows. Is trimming from both ends required to utilize them? Or are they designed to hang up on both ands of the barrel window then just push through more in the middle, if you will. I hope that made sense. :S

Yes they are too long, kinda annoying that they are too long to fit in Prometheus barrels. You do need to cut them with a razor blade so it fits snugly. My Firefly nub is actually the same length as my Prometheus ones, so I can't really blame Prometheus here lol

[ThunderCactus]

I've had a low fps problem with a customer's gun that turned out to be both the chamber and rubber.
He had a PDI-W in there, said it was no good. But the gun could barely feed BBs past the lips because they were too tight.
Changed to R-hop and modify flat rubber, same issue. Poorly casted chamber tapered inside and put extra squeeze on the hop rubber's lips. Just sanded them out a bit and it worked great after.
With the rubber in the chamber, it should take a very minimal amount of force to move the BB past the hop rubber's seal

[Stealth]

I've had shit results with the Madbull bucking in anything other than a Madbull unit, which IMO sucks because the tolerances of the arm were way too loose. Teflon tape on the PDI W-Hold as necessary, but really, if you're doing proper install/testing, that should be obvious by now.

I think the biggest takeaway is really this:

Originally Posted by Rabbit

In conclusion there are MANY variables when it comes to selecting a consistent match for hop up units and everything else used in conjuction.

Just because me and a bunch of users sing the praises of one rubber over another doesn't always mean it's a magic drop-in solution. As with anything airsoft, some ingenuity and fiddling may be required to achieve optimal results.