CA P90, prowin and nozzle help

[Ichkabible]

Hey guys, I recently got a prowin hop up for my CA P90, and when I installed it and tested it, the bbs simply will not come out of the gun. I pull the mags (dboys low caps) and there is three bbs in the hop as usual. I removed two so there was just one sitting there ready to go and shot and it just sits there. I switched back to my stock hop and it shoots fine. I'm thinking the nozzle is too short maybe?

I still have the stock nozzle in there since it seals better to the lonex cylinder I have installed. I also have a modify nozzle here but as I said, it does not seal as well to the cylinder head.... But I'm pretty sure it's longer....

I have access to cnc machines and a machine shop as well as a professional machinist or two, so i have no limits here, but I still wanna keep it simple if I can, any ideas? (Other than leave it stock)

[Kos-Mos]

Your nozzle is too long to fit the prowin hopup.

Try tapering/chamfering the top tip if the nozzle like this and see if it helps.
DO A LITTLE AT THE TIME.

[lurkingknight]

is the BB falling into the path of the nozzle and not shooting or is it sitting on top of the nozzle and not shooting?

is the nozzle capable of inserting completely into the hopup unit without obstruction without a bb there?

[Spike]

Cycle the gun till the nozzle is in the fully back position. Will a BB pass through?

It's probably too long, like has been said. Compatibility with aftermarket hop up units can be a bitch. Honestly if your stock unit works, there's not much of a point in changing it.

[Ichkabible]

Originally Posted by lurkingknight

is the BB falling into the path of the nozzle and not shooting or is it sitting on top of the nozzle and not shooting?

is the nozzle capable of inserting completely into the hopup unit without obstruction without a bb there?

Yes the bb falls in the path of the nozzle. The nozzle hits the bb but does not push it past the bucking lip.

I can't really tell if the nozzle goes completely to the bucking but it does fit in the hop fully. I will test this further at a later date as I suspect the nozzle is to short, not to long as was mentioned above. If you look down the top of the hop straight on you cannot see the bucking. If you look the same way at the stock one, it is slightly protruding. So the bucking is deeper in the prowin.

[Ichkabible]

Originally Posted by Kos-Mos

Your nozzle is too long to fit the prowin hopup.

Try tapering/chamfering the top tip if the nozzle like this and see if it helps.
DO A LITTLE AT THE TIME.

How is making it shorter going to help? The bbs feed fully but cannot get past the bucking lip. Thanks for the tip about the tip though 😜

[Ichkabible]

Originally Posted by Spike

Cycle the gun till the nozzle is in the fully back position. Will a BB pass through?

It's probably too long, like has been said. Compatibility with aftermarket hop up units can be a bitch. Honestly if your stock unit works, there's not much of a point in changing it.

The bb goes in when the nozzle is back. I got all winter to make this right and I already got the part so I may as well make it work.

[lurkingknight]

Originally Posted by Ichkabible

Yes the bb falls in the path of the nozzle. The nozzle hits the bb but does not push it past the bucking lip.

I can't really tell if the nozzle goes completely to the bucking but it does fit in the hop fully. I will test this further at a later date as I suspect the nozzle is to short, not to long as was mentioned above. If you look down the top of the hop straight on you cannot see the bucking. If you look the same way at the stock one, it is slightly protruding. So the bucking is deeper in the prowin.

take the gearbox out of the gun

cycle the gearbox or reset the gears until the nozzle in full forward position

align the gearbox with the body and push it in slowly. observe the nozzle through the hopup feed tube. When you push the gearbox all the way in, the nozzle should not stop and go all the way into the hopup chamber.

To test if the nozzle is properly sealing to the bucking, partially block the barrel and put a piece of tissue paper over the feeding hole. Cycle the gun in semi. If partially/mostly blocking the airflow from the barrel and the tissue shoots off with some force, the nozzle is not sealing to the bucking. So either the hopup unit is longer than the original or it's holding the barrel assembly farther away than stock.

Why would you want to change hopup units anyways? If there is nothing wrong with the one you have, there's no reason to change it. The whole misconception people have is that metal is better. no, not necessarily.

CAs should have come with a metal unit anyways unless it was a sportline, then I'm not sure what unit those things come with, but I've only ever seen a metal unit on a ca.

[Ichkabible]

Originally Posted by lurkingknight

take the gearbox out of the gun

cycle the gearbox or reset the gears until the nozzle in full forward position

align the gearbox with the body and push it in slowly. observe the nozzle through the hopup feed tube. When you push the gearbox all the way in, the nozzle should not stop and go all the way into the hopup chamber.

To test if the nozzle is properly sealing to the bucking, partially block the barrel and put a piece of tissue paper over the feeding hole. Cycle the gun in semi. If partially/mostly blocking the airflow from the barrel and the tissue shoots off with some force, the nozzle is not sealing to the bucking. So either the hopup unit is longer than the original or it's holding the barrel assembly farther away than stock.

Why would you want to change hopup units anyways? If there is nothing wrong with the one you have, there's no reason to change it. The whole misconception people have is that metal is better. no, not necessarily.

CAs should have come with a metal unit anyways unless it was a sportline, then I'm not sure what unit those things come with, but I've only ever seen a metal unit on a ca.

Thanks for the tip, that is a great idea! I'm changing hop ups because my guns Fps varies bye +- 20 and I have done all the internal mods for compression. Stretched O ring, 8 port lonex piston head, lonex double seal cylinder head which I siliconed to the cylinder, tapet plate is filed down, and during compression test with the nozzle forward in shooting position I cannot push the piston in all the way, so that area is good. I use permatex on my bucking as well as tephlon tape and dental floss, the bucking is a prommy red, on a prommy barrel with r hop. So my thinking is that maybe the stock hop is not perfectly round, since it's two piece, and therefore not sealing completely. Or I botched the bucking when I flipped it, but I'm thinking fps would be much worse if the bucking was botched. Unless I'm missing something? I am going to get prommy blue straight bucking next week to eliminate any bucking issues and borrow this down further. My goal is +- 2 fps