P90 hi cap issues.

[nicditty98]

I recently bought a king arms p90 AEG. The gun it self is amazing, but the high caps are less than par. First off, they have the classic p90 hi cap feed issues, and I can deal with that. The big issue is with winding it up. I'll wind it, waiting for it to click, and the release let's bb's fly out. I'll hold the release shut aND everything will be fine, but if I don't hold it while winding the bb's will shoot out like crazy. What can I do to fix this. I'm gonna buy mid caps but I also want to use some hi caps. Any advice would help

[Snarf]

One of my friends had a P90 for a bit. The mag was one of the reasons why he flipped it. It was terrible.

If you're going to buy midcaps, just use midcaps. This forum is generally pro midcap and anti hicap, because most people seem to be MILSIM players.

[snafu]

The Tokyo Mauri hi caps are actually the best you can get for the p90, what makes them great is that they are gravity fed and you don't have to wind them once more than once. That being said, mid caps are what everyone wants and unfortunately with the p90 options are very limited. You can buy 68 round TM mags or the hit or miss MAG 180 rounders. When I bought a case of thE MAG brand 2 of the 4 wouldn't feed at all, one of which I was able to modify to work after some time. The other never worked..

[X]

P90 high caps are not gravity fed.

[Elvis]

I may be wrong but I am guessing that tokyo mauri high caps may be on a slight angle allowing the bb's to roll down

[X]

You are wrong.



P90 High Caps have a big follower that forces the BBs into the feeding mechanism.

[Elvis]

I am aware of how p90 high caps work, what I was saying is if they worked the traditional way but did so on a slight angle, enough for the bb's to roll down by them selves and being pushed by the thing.

[Gunny87]

Nov 17, 2014 0:32:32 GMT -5 snafu said:

The Tokyo Mauri hi caps are actually the best you can get for the p90, what makes them great is that they are gravity fed and you don't have to wind them once more than once. That being said, mid caps are what everyone wants and unfortunately with the p90 options are very limited. You can buy 68 round TM mags or the hit or miss MAG 180 rounders. When I bought a case of thE MAG brand 2 of the 4 wouldn't feed at all, one of which I was able to modify to work after some time. The other never worked..

Nov 17, 2014 10:38:27 GMT -5 X said:

You are wrong.

P90 High Caps have a big follower that forces the BBs into the feeding mechanism.

I would argue that you both are correct. Yes, the P90 uses a follower when the magazine is wounded to move the bb's into the opening of the magazine but it's still gravity that forces the bb fall into the hop up chamber from the top. As opposed to most magazines that require a spring with a follower attached at the end to force the bb's up into the bottom of the hop up chamber.

Anyways, to the OP. If you must use P90 high caps, spend the extra money and get a Tokyo Marui P90 high-cap magazine. But really, you're better off just getting midcaps and only using midcaps. I've owned five P90s over the years and I've only experienced one high cap work for a while which was a Tokyo Marui P90 Hi-cap as snafu suggested.

If using and carrying P90 midcaps is going to be a problem for you, then I suggest getting a new gun.

[X]

That's still not true Gunny. If anything one could argue an M4 high cap is partially gravity fed.

When you wind a high cap mag (M4 or P90) you are winding what's called a clock spring. Pic below for reference.





The tension of this spring turns a sprocket that forces the BBs into the hop-up on both designs. The M4 type (similar to above) has a cavity in the magazine where the BBs reside. In this style magazine gravity does in fact feed the wound spring which then uses it's stored energy to lift the BBs into the gun. With a P90 you have exactly the same setup except since the magazine is horizontal you can't use gravity to feed the spring. To solve this they use a large follower powered by a compression spring (similar to a real magazine) that basically replicates what gravity would do for an M4 mag.

A simple way to prove this is too take a P90 with a high cap and shoot it upside down (or any orientation). I guarantee it will work. The M4 will not because the bbs cannot be fed into the sprocket at the bottom of the mag. It will shoot a few times then you'll hear the ZOOOM of the sprocket free spinning releasing all of it's stored energy. This happens because there is nothing to block the sprocket from moving.

I think the P90 mag design is superior to the other high caps. The spring can store enough tension to feed the entire magazine and it can be used in any orientation. I have only ever used TM high caps and they have worked great.

For the OP the problem that you have is the magazine stopper which holds the bbs in the mag (don't know the technical name) is either broke, stuck, or the spring which forces it closed is weakened or missing entirely. If you take a picture of where the BBs come out we could eliminate a few of those possibilities.