Prometheus new-fangled hop-up

[sharingan]

Well I also have a jamming issue. You guys said that the feeding lip is too thick. Could someone post a picture where to remove the material? I compared it with a guarder hard bucking and found out that the feeding lip of the Promi is slightly longer -> Is it enough to shorten the feeding lip?

[kojak]

Shortening it is most likely going to have a negative effect on airseal; if anything I'd try increasing the inner diameter of the feed lips. Maybe a conical sanding bit?

 

I didn't bother, it's much easier to use a bucking that feeds and just shave the ridge and bump yourself.

[gijohn2]

Tested this set up yesterday....it was poor! There was no flat trajectory it just spun up then down onto the target 50meters away. My friend got better results with a element blue rubber with H nub. I would advise not buying any of these

[kojak]

Are you using a stock barrel? The "bump" created by this bucking/nub combo is much larger than a stock barrel window, so it won't work as intended.

[dwong]

I was finally able to test this yesterday, and overall I'm pretty pleased. The setup I used was a Madbull 6.03 300mm barrel, generic shaved bucking, and the bridge nub. My fps was 400 chronoed with .2s and I used .3g bbs (bioval and goldenball). I was able to get a consistent flat trajectory to about 150-170 ft estimated using Google Earth. I think a slightly longer barrel would be able to squeeze a bit more range out of this setup, and I will try out a 363mm madbull next weekend. A few things to note would be that I lengthened the window on my barrel to achieve contact from the entire length of the nub, and I have yet to get the prometheus flat bucking to work. I think with an unmodified barrel you would have to trim the nub to fit the window, otherwise it'd pinch and give you strange trajectories. I haven't been able to compare this with the rhop yet since that setup put me over field limits.

[kojak]

I was able to widen the feed lips of the Prometheus flat bucking with a conical sanding bit on my Dremel tool. I had to turn it inside out partially so I could remove a bit of material from the inside of the lips as well as the outside, and I kept the barrel and chamber handy so I could check the fit and avoid sanding too much.

 

Eventually I sanded it enough that the BB stops at the feed lips but can be pushed through with very light pressure.

[coolurjets]

Mine has arrived today, Bridge type nub and straight bucking. I will post up the results in a few days. I've got a Classic army G36 hop unit and a Lonex G36 hop to test in with a Madbull v2 barrel,

I'm hopeful on the Lonex Chamber as the inside diameter is a shade to large for the marui buckings.

[coolurjets]

The install went ok. The Prometheus straight bucking did arrive very dry and hard so i gave it a soak in silicone over night.The Bridge nub was the perfect width for the Lonex chamber, no problems should arise about the groove being off center. I had to trim down the front and rear quite a bit though, but that was quite straight forward with a scalpel. I am using the soft type nub to start with as the gun is 320 fps (for UK CQB limits). Visual inspection of the hop effect seems to give good range from totally off to a significant amount of hop, so over hopping should not be an issue. However I've hit the same problem with the bucking neck being too tight to let BB's in. I will gently attack this over the weekend.

 

I remain vaguely optimistic...

[sharingan]

I finally get a chance to test the setup in the field..custom m16 with element m4 chamber. Well on every second single shot i will get double feed (2 bbs comes out). I already trim down the front. Well im dissapointed.

[coolurjets]

Update: After taking a Dremel with some rolled 600 grit paper and gently widening the neck of the Hop Bucking, I set out for the first Skirmish with the new set up.

 

Lonex G36 Hop chamber, Madbull V2 6.03 tightbore, Prommy Straight bucking and soft Bridge nub (Trimmed length ways to fit the G36c chamber).

 

This was a bit of a mixed bag of results. Misfeeds, double feeding, and the occasional no feeds. However when the gun did fire consistently the range/consistency was quite impressive, I was able to easily harass people who thought they we're safe outside 'normal' aeg range. But still, utterly hampered by feeding issues.

 

After the game day I widened the neck of the hop rubber further and this seems to have sorted out the feeding issues of the set up, gives good air compression and kept the great range. I'm not familiar enough with R-hops to claim comparison but this is definitely a great improvement over 'Standard' hop set ups. Just as other people have found, the Prometheus straight buckings are really not worth the effort as you can mod any hop rubber to the same effect.

 

This I did with a Madbull shark 60 degrees bucking in a Madbull Ultimate Hop unit, the second Bridge nub installed into this hop unit without the need for modification and also gave equally great results. I've been able to get really flat trajectories using .25g bb's in both set ups.

 

So the Prommy Bridge nubs to seem to be worth it, may require a little bit of modification. The Prommy Straight bucking, not really worth it.

[hunter512]

Running an ICS galil fitted with a prommy tightbore with the soft bridge and the hop rubber, took a LOT more noticeable bedding in period during which it literally threw bb's everywhere. Since then I cannot give specific figures but it has felt a lot tighter and more accurate, plus has got rid of the right hook that my galil had out of the box.

[hunter512]

Oh and for completeness sake stock G&P hops do not play nice with the Prommy bridge buckings

[kenofchaos]

would this type of bucking be suitable for use in a real sword SVD???????