Dominator International 870 Shell Ejection shotgun, new system?

[Katotaka]

PPS Orange shells don't work well with anything stronger than normal green, e.g. WE 4X.

[Wingmann]

I'd have one of these shotguns, but then I think about it and reason takes over...

[blobface]

[swatti]

Yay... More shell ejectors. Meh.

 

My PPS purple shells utterly died when using Co2.

Speaking of, does anyone know of a working email to PPS? Their contact form in their site is broken. Obviously.

 

Friend of mine gave me an interesting idea about a triple barrel system that could easily shoot 6 or 9 rounds with spring power and light cocking action.

Internal magazine too.

 

Prototype in the works.

[PureSilver]

My PPS purple shells utterly died when using Co2.

 

Damn, and you were the source I was relying on for how good they were with CO₂! How hard would be they be to fix?

[Katotaka]

 

Damn, and you were the source I was relying on for how good they were with CO₂! How hard would be they be to fix?

 

I used to run CO2 on my purple shells, they're OK if they're fired within a short time like 10-15 min, after that the o-rings will swell badly and probably seize the primer.

 

I gave up and switch to WE 4X and Guarder gas with black fat canister.

[swatti]

I had a VERY odd issue with the shells.

 

The trigger button "backfires" backwards at an INSANE strength. I think the valve opens so fast it hits the button backwards.

 

That power is enough to crack the end cap of the shell. That end cap is made of steel btw.

 

BUT! Not all of the shells have that issue. They all backfire at least a bit but some far less than others.

EDIT: all moscarts backfire too, very little but they do.

 

It seems some shells are a different generation then others.

I have six shells and couple of em have different size components.

 

I've tried all combinations of parts but can't figure out what causes the backfire.

 

I do have a potential fix. The spring in the valve. Replace that with a stupidly stiff one. That would lessen the backfire enough so it won't kill the shell.

Local gun-store is my source for springs, il post what spring it is if I find a replacement.

 

Also. The O-rings. Some get bloated and die, some are too thin and pop off releasing the gas in your pocket with pop-sound. They won't "fire" in your pocket.

The main seal is also too soft and fat. Resetting the shell may cause it slice off a part of the seal resulting in leaks.

 

I have bought a bulk package of O-rings and fixed the problems. I'l post sizes when I get home.

 

These shells are bit too high maintenance imo, but I'd let it slide if I got them to work reliably.

The performance is very good with Co2 and my god, the noise, orgasmic.

[Katotaka]

That backfire issue is another reason that I stopped using CO2, that will also break firing pin and bolt if you're still using plastic one.

 

I then filled the holes underneath the bolt w/ epoxy and made these:

SLS printed nylon, strong as *fruitcage*, and still have 19 more replacements if you manage to break one.

 

BTW, shells from Alpha Parts have much stronger base but the upper part is , if you're interested.

 

To be frank I wouldn't think spring will help, because when they hit the base, the primer and the cap(that holds 4 ball bearings) are sticking together.

 

 

Main seal will swell shortly after use even it discharged the shot normally, I would let the shells "rest" a while before resetting them. Some base can get loose causing the bigger o-ring on the cap "not big enough", I replace them with slight bigger ID ones, while original one is 9mm ID x 1.5, that the new ones will be 9.5ID and 10ID x 1.5 thickness.

 

 

Yeah, I also love the BANG of CO2 shots, and I could feel a very very slight recoil from the discharge, but then I stopped using CO2 and suddenly almost no maintenance needed.

 

Contact me if you decide to switch and you may need these 

[swatti]

Are those part of the gun? You see, I don't have a PPS shotgun. I use the shells in my own self-made shotties.

 

We don't have regular gasses here much, propane is in 13kg tanks, green gas can cost about 30 bucks a bottle.

 

Co2 on the other hand I can fill 600g for 4 euros.

 

Million dollar question is, why do some shells backfire so heavily and some almost not at all? Answer that and win the interwebz.

 

I replaced my main seal with one made from material that can withstand huge temperature variations and corrosive stuff. Seemingly identical size but lot harder.

 

All the other seals I replaced with bit thicker and lot harder ones.

 

Are the bases sold separately anywhere? Never heard of this alpha parts... Do they have a contact email, I could ask for the bases if they are compatible.

[Katotaka]

Are those part of the gun? You see, I don't have a PPS shotgun. I use the shells in my own self-made shotties.

That's the actual firing pin part that hits the primer from a PPS 870, yes they backfire so much that will break the bolt/firing pin/etc.

 

We don't have regular gasses here much, propane is in 13kg tanks, green gas can cost about 30 bucks a bottle.

Co2 on the other hand I can fill 600g for 4 euros.

Ouch that's expensive, I see why you're sticking with CO2 there...

 

Million dollar question is, why do some shells backfire so heavily and some almost not at all? Answer that and win the interwebz.

Not sure, I just reinforce the mating parts so they can withstand the impact.

 

I replaced my main seal with one made from material that can withstand huge temperature variations and corrosive stuff. Seemingly identical size but lot harder.

All the other seals I replaced with bit thicker and lot harder ones.

I'm definitely interested in that, if that works in CO2 it would work better in Green.

 

 

Are the bases sold separately anywhere? Never heard of this alpha parts... Do they have a contact email, I could ask for the bases if they are compatible.

Not sure, just a reminder, you don't want to run CO2 in those shells straight out of the box.

[swatti]

No small suprice, Airsoft Mechanics topic isnt raising much interest...

"The beginning of the end"

 

https://scontent-frt3-1.xx.fbcdn.net/v/t1.0-9/13932865_1286536154719878_8940989097883358310_n.jpg?oh=1933b7e76831dde88741c131bd801c03&oe=58216A24

 

"... And when it did end"

 

https://scontent-frt3-1.xx.fbcdn.net/v/t1.0-9/13882268_1286753501364810_1036113485515813052_n.jpg?oh=c391bb23cbb5539841d3c0a75c6087d9&oe=585D6E93

 

 

Still, the "oddity" is that not all shells backfire. Before and after O-ring swap, they behave the same. The only thing you can do really is to lube em and swap the O-rings. 

 

The CO2 i use is in gas form. I have means to run it out in both liquid and gas. Liquid would most likely destroy the shells even faster.

 

APS shells need the plastic wads and the paper wad. We take ~5min breaks between games and im fat, slow walker, mostly last to get back and barely have time to fill my rattle-caps. How am i suppose to fill up those!?

[Katotaka]

Yep I had similar deforming pattern in some of my shells, I just stopped using and tear them down for spares. If I can get spare bases I could get them running again.

 

 

Considering your condition, you don't have much options and you must deal with it. (Sorry for pun, I saw you're from Finland and I thought about Hydraulic Press Channel.)

[Wingmann]

Getting them done in CAD then CNC in steel?

[blobface]

 

[Roland1014]

Anyone got one?

[NonEx]

Anyone here cal tell me if APS CAM870 shells would fit in a PPS 870 shell holder? :o

 

http://shop.ehobbyasia.com/pps-cnc-6-shell-carrier-for-aps-pps-m870-shotgun-870-qac-008-1.html#.WQPhf4h95aQ

[Katotaka]

the shells would probably fit but the carrier's pins location are way off

[NonEx]

The shells do not really fit out of the box.

 

In the shell holder there is a plastic/PVC tubing running along the inside "spine" of the holder which protrudes slightly into the actual shell holes. This is too thick and puts too much pressure to fit the APS shells.

 

But if you replace it with a slightly smaller plastic tube or something similar it will work :D

 

Have not checked the pin holes yet.