Author Topic: Weird PP700 stuff (Read 9317 times))

YEMX · « **on:** July 14, 2019, 03:42:30 PM »

Another thread got my brain rolling...

I found this on Aliexpress:
https://www.aliexpress.com/item/32819121608.html?spm=2114.search0104.3.9.383e2535CCAu7t&ws_ab_test=searchweb0_0%2Csearchweb201602_1_10065_10130_10068_10547_319_10546_317_10548_10545_10696_10084_453_454_10083_10618_10307_537_536_10059_10884_10887_321_322_10103%2Csearchweb201603_53%2CppcSwitch_0&algo_expid=6858051f-65bd-4e76-9422-905e22829a56-1&algo_pvid=6858051f-65bd-4e76-9422-905e22829a56&transAbTest=ae803_5

Basically, it's a drop down adapter for an AF gun... The idea is to use it as an adapter to attach a small 350cc tank to the gun, replacing the reservoir. I know there'll be more work to make this adapter work, but would THIS adapter work?

I'm thinking maybe making a short-ish prechamber, throw this on the end of it and make an adapter for the tank side. Thoughts? There's a cheaper one of these as well, $41. They look to be the same.

Motorhead · « **Reply #1 on:** July 14, 2019, 05:02:13 PM »

sadly NO
The PP700 would require a drop block that had the same receiver mounting pattern of the regulator ( 4 bolts in an off square pattern )
Am surprised with this topic coming up fairly often sense these pistols came out that no one has stepped up and produced such a drop block.

YEMX · « **Reply #2 on:** July 14, 2019, 09:03:37 PM »

Quote from: Motorhead on July 14, 2019, 05:02:13 PM

sadly NO
The PP700 would require a drop block that had the same receiver mounting pattern of the regulator ( 4 bolts in an off square pattern )
Am surprised with this topic coming up fairly often sense these pistols came out that no one has stepped up and produced such a drop block.

Well, the idea would be to reuse the original silver part that threads into the gun, and re-use a section of the factory tube to create a sort of pre-chamber. Then make a coupler that threads into the pre-chamber and this drop adapter... Then the other side of this drop adapter would have another coupler to go between the drop down and either the tank or the tank's reg...

Did That make any sense? I have a hard time properly describing what's in my head... I'll draw a quick pic and post it if you're having trouble picturing what I'm typing...

Motorhead · « **Reply #3 on:** July 14, 2019, 11:25:17 PM »

Makes sense and also a LONG air bottle configuration. ideally JUNK the OEM reg and use a NINJA type at the bottle connection.

Tho said ... more than 1 way to skin a cat

YEMX · « **Reply #4 on:** July 15, 2019, 12:54:17 AM »

Quote from: Motorhead on July 14, 2019, 11:25:17 PM

Makes sense and also a LONG air bottle configuration. ideally JUNK the OEM reg and use a NINJA type at the bottle connection.

Tho said ... more than 1 way to skin a cat

Oh absolutely... I'm taking my PP700 apart... I want to see what I'm working with... I know I don't need one, but I think I'm going to re-design the rotating breech block so I can have a bolt handle... I do so love those USFT's... Maybe use something silly, like a 22xx knob or something.

In my original build, I "deleted" the factory reg and I have installed a HuMa- that's why I wanted to to retain the original silver adapter part, and re-use part of the original reservoir. I could retain the HuMa reg and just use a tank... The length of the original reservoir (if I can even use it) would only be as long as needed to house the HuMa reg and the drop down adapter... adapter? End cap? I'm not sure how to word that.

Another idea is... Junk the original silver part as you mentioned, and make a new one that's hogged out as much as possible (not really looking for too much flow, as this is gonna be a .20 or .22, 15 fpe or so). Maybe use a section of Mrod main tube. They LOOK the same. I'll take measurements tomorrow. If I can use/modify a section of Mrod tube, I can use a Brod conversion block for this build... Maybe. Dunno. Just a thought.

YEMX · « **Reply #5 on:** July 15, 2019, 06:18:13 PM »

If I do go down the bottle conversion route, I think I'll definitely scrap the factory reg body (silver piece) and just make (or have made) a new one. The Mrod tube and factory PP700 tubes are close- 1.25" vs. 1.26" respectively. Which means I can use a section from the front of a scrapped Mrod tube and use a Brod conversion block to do the bottle conversion...

What am I getting myself into?

Rallyshark · « **Reply #6 on:** July 16, 2019, 12:48:08 AM »

If you really want to wake the gun up and give it some more potential, then enlarge the hole that the air travels into the gun from. The one that sits between the two o-rings on the silver piece is what I'm talking about. That hole is tiny. You can only take it so far with the factory silver piece in place, BUT if you're removing that silver piece(factory reg housing), then you should be able to make a pretty good improvement in air flow to the valve. You could also give the gun an actual plenum to work with too while you're at it! If you're able to do that stuff, then it will be a whole different animal me thinks

YEMX · « **Reply #7 on:** July 16, 2019, 12:53:24 AM »

Quote from: Rallyshark on July 16, 2019, 12:48:08 AM

If you really want to wake the gun up and give it some more potential, then enlarge the hole that the air travels into the gun from. The one that sits between the two o-rings on the silver piece is what I'm talking about. That hole is tiny. You can only take it so far with the factory silver piece in place, BUT if you're removing that silver piece(factory reg housing), then you should be able to make a pretty good improvement in air flow to the valve. You could also give the gun an actual plenum to work with too while you're at it! If you're able to do that stuff, then it will be a whole different animal me thinks

That's the plan! I'm not trying to make this a MONSTER, but I'd like to make improvements where I can and let the whole system breathe better... I WILL be making a new "silver piece", because I'd rather make a coupler that's sized for the Mrod tube, rather than making an adapter to fit the factory stuff... I'm not sure if that made sense... $:-\$ As soon as I get it disassembled, I'll start posting pictures and such.

JungleShooter · « **Reply #8 on:** July 16, 2019, 09:06:44 PM »

Tom, SUBSCRIBED!

Very interesting, keep us updated. I'd be interested as long as the thing doesn't get any longer..., bulkier is fine, just not longer, rather shorter if anything....!

Matthias

YEMX · « **Reply #9 on:** July 16, 2019, 09:46:16 PM »

Quote from: Rallyshark on July 16, 2019, 12:48:08 AM

If you really want to wake the gun up and give it some more potential, then enlarge the hole that the air travels into the gun from. The one that sits between the two o-rings on the silver piece is what I'm talking about. That hole is tiny. You can only take it so far with the factory silver piece in place, BUT if you're removing that silver piece(factory reg housing), then you should be able to make a pretty good improvement in air flow to the valve. You could also give the gun an actual plenum to work with too while you're at it! If you're able to do that stuff, then it will be a whole different animal me thinks

How much larger do you think we can go?

YEMX · « **Reply #10 on:** July 16, 2019, 09:53:39 PM »

Quote from: JungleShooter on July 16, 2019, 09:06:44 PM

Tom, SUBSCRIBED!

Very interesting, keep us updated. I'd be interested as long as the thing doesn't get any longer..., bulkier is fine, just not longer, rather shorter if anything....!

Matthias

I'm not trying to go longer unless I have to. But even if I have to go longer, it will only be as long as is necessary to put the LDC threads past the tank.

Okay, this is what's in my head so far for the overall build:

- New "silver piece" with a larger port and made to fit a Mrod tube
- Mrod tube length is to be determined
- Brod bottle adapter
- 200 cc bottle (because I already have one)
- Breech will have both those pellet loading tabs (JSAR breech) and also more material so I can add a bolt handle (yeah, I don't NEED it, but so what?)
- Folding stock similar to KRG Whiskey 3 chassis. Probably the same kind of grips, since I have a set here to play with

Other than that, I'd like to re-use the rest of the factory parts. I'll figure it all out as we go along. I'm really hoping to be able to re-use that HuMa reg w/the Mrod tube, so I can just thread the bottle into the Brod adapter and keep the OAL as short as possible.

What I'm really hoping, with regard to the bottle stuff:

- 200 cc tank w/just the adapter to direct thread into the Brod conversion block (to keep OAL short)
- Able to reuse the HuMa reg
- The 200 cc tank/Brod adapter is short enough so that I can have a decent sized pre-chamber in front of the HuMa reg... Not sure what's an appropriate size. I'd like to keep this pistol around 15-20 fpe... Or maybe 30 fpe if the new "silver piece" with larger through port works out. For now, I'm going to keep the energy conservatively at 15-20 fpe... Again, this is all hopes and speculation right now!!

Rallyshark · « **Reply #11 on:** July 17, 2019, 06:23:09 AM »

I can't wait to see how this turns out! You are definitely going to need to come up with some plenum one way or another to reach the higher end of the numbers regulated I think. I completely bored out the factory reg housing on mine, and was able to reach 25fpe in .177 unregulated, but 20fpe is the upper limit on regulated power with mine. Back before the FB group for these was shut down, one of the guys did a bottle with drop block on his. I think he was able to get it close to 30fpe in .22., but I can't remember what kind of drop block he used. I know he installed a pressure gauge on the side of the breech to show regulated pressure.

I think you'll end up with a cool little beast either way

YEMX · « **Reply #12 on:** July 17, 2019, 08:48:31 AM »

It'll be a fun build for sure! I'm definitely going to keep this build more modest, I don't want to even attempt to go above and beyond what is realistically capable for this platform... So 15-20 fpe is still the main focus... Once I get the gun apart, I can do some real preliminary mock ups...

Rallyshark · « **Reply #13 on:** July 17, 2019, 08:34:37 PM »

Quote from: YEMX on July 16, 2019, 09:46:16 PM

Quote from: Rallyshark on July 16, 2019, 12:48:08 AM
If you really want to wake the gun up and give it some more potential, then enlarge the hole that the air travels into the gun from. The one that sits between the two o-rings on the silver piece is what I'm talking about. That hole is tiny. You can only take it so far with the factory silver piece in place, BUT if you're removing that silver piece(factory reg housing), then you should be able to make a pretty good improvement in air flow to the valve. You could also give the gun an actual plenum to work with too while you're at it! If you're able to do that stuff, then it will be a whole different animal me thinks

How much larger do you think we can go?

I missed this part earlier. If you are able to push the rear facing o-ring as far as possible to the rear of the new silver piece you are going to make, I think you can probably open up that hole at least close to bore size, but it may need to be a bit oval shaped. The factory hole is probably less than .100 if I remember correctly. I would have to look at it again to be sure on that though. You shouldn't have any problem figuring out how much you can open it once you get it apart I don't think. If not for that tiny hole, I think I could have gotten my .177 over 30fpe. I wasn't able to open it very much at all with the factory reg housing.

YEMX · « **Reply #14 on:** July 18, 2019, 06:32:41 PM »

Well... I got the pistol apart and did a mock-up... Good news and bad news folks. Bad news first:
We're gonna have to make the gun longer. Even with no plenum, the barrel won't clear the tank. This is a 200 cc tank too, a 350 cc will be even longer. Now, how much longer depends on a few things- how long to make the plenum, whether or not the Huma can be re-used in the Mrod tube or if I have to go with a Ninja clone reg... The good news is that the Brod bottle drop adapter will work!!
Just barely, but it really looks like it'll work. That's with the barrel shroud on. I plan on re-using the LDC adapter. Anyhoo, real basic mock-up here:

Rallyshark, which hole are you talking about enlarging?

This one:

Or this one:

After doing some measuring, I came to the conclusion that I CAN re-use the Huma reg in a Mrod tube, so we're good. Also, some more "bad" news. The factory tube length is basically what I'll need to have 30 cc's+ of air after subtracting the space needed for the Huma and the bottle conversion block.

Which is fine, but I'll need to have a 17-18" OAL barrel so I can mount an LDC... I'll have to figure out what I'm going to do about the barrel... If I can go bigger on the O.D. of the barrel, I will. I don't think I have the room for it though. It's probably why they went with such a thin barrel- to have more material up front to clear the air ways to the valve...

EDIT:

Man, that barrel really IS thin... At the rear, where the o-rings are, the sleeve is .472" O.D. The barrel itself is about .392"... There MIGHT be enough room to make the barrel bore .472" all the way through... I guess I could secure the barrel with a grub screws in the dovetail- that way they can be hidden when I put on a scope...

For those that have messed with the pistol- do you think there's enough room to up the barrel bore to .472" all the way through, or will I hit an air way?

Rob M · « **Reply #15 on:** July 18, 2019, 08:28:59 PM »

what about simply doing an Mrod tube with an offset ( eccentric non centered ) adapter to fit the inlet of the gun .. in other words.. it would just be a pp700 with a regged and shortened marauder tube , same front end fill assembly.. same everything but shortened with a read adapter ( which would be the hard part to make

YEMX · « **Reply #16 on:** July 18, 2019, 09:28:01 PM »

What would be the point of that be? That's just a PP700 with extra steps, and a foster fill instead of a probe... Also, there's no need for an offset adapter if using an Mrod tube, since an Mrod tube and a factory PP700 tube is nearly identical. At least in my case- as I measured my examples of both the PP700 tube and Mrod tube here at the house, with my (not extremely accurate but good enough) instruments...

I'm trying to add a bottle to my PP700 and keep it as short as possible so that I can have a compact foldable carbine with more air...

Although, you do bring up a viable option if I decide to possibly go with a longer barrel... That is, if I can open up the receiver's barrel bore w/no issues... That's a touch less than 17.25" of a longer tube. Hmmmm... I might have to buy a 2nd PP700 and see what this contraption would look like!

Rob M · « **Reply #17 on:** July 18, 2019, 09:30:01 PM »

Quote from: YEMX on July 18, 2019, 09:28:01 PM

What would be the point of that be? That's just a PP700 with extra steps, and a foster fill instead of a probe... Also, there's no need for an offset adapter if using an Mrod tube, since an Mrod tube and a factory PP700 tube is nearly identical. At least in my case- as I measured my examples of both the PP700 tube and Mrod tube here at the house, with my (not extremely accurate but good enough) instruments...

I'm trying to add a bottle to my PP700 and keep it as short as possible so that I can have a compact foldable carbine with more air...

Although, you do bring up a viable option if I decide to possibly go with a longer barrel... That is, if I can open up the receiver's barrel bore w/no issues... That's a touch less than 17.25" of a longer tube. Hmmmm...

ok i forgot the PP700 actually had a pretty fat tube .. something along the lines of 32 mm o.d..

YEMX · « **Reply #18 on:** July 18, 2019, 11:01:38 PM »

Quote from: Rob M on July 18, 2019, 09:30:01 PM

ok i forgot the PP700 actually had a pretty fat tube .. something along the lines of 32 mm o.d..

No worries!

Yeah- it's 1.26" O.D. Or, "close enough to an Mrod to work"

Considering my goal is realistically a max of 20 fpe, I should be able to drop an inch or two off the factory tube, re-thread it for the Brod adapter, and re-make that rear end cap. Or possibly just open up the through hole a touch, since there won't be any guts in there. Throw in a plug for the back of the silver piece and I should be able to call it a day... What are y'all's thoughts on this? Again, realistically I'm looking for a max of 20 fpe. I'd probably tune it for around 12-15 fpe.

I started farting around w/the KRG grips to see what I can do with them... It's looking very promising!

Rob M · « **Reply #19 on:** July 18, 2019, 11:55:00 PM »

Quote from: YEMX on July 18, 2019, 11:01:38 PM

Quote from: Rob M on July 18, 2019, 09:30:01 PM
ok i forgot the PP700 actually had a pretty fat tube .. something along the lines of 32 mm o.d..

No worries! Yeah- it's 1.26" O.D. Or, "close enough to an Mrod to work"

Considering my goal is realistically a max of 20 fpe, I should be able to drop an inch or two off the factory tube, re-thread it for the Brod adapter, and re-make that rear end cap. Or possibly just open up the through hole a touch, since there won't be any guts in there. Throw in a plug for the back of the silver piece and I should be able to call it a day... What are y'all's thoughts on this? Again, realistically I'm looking for a max of 20 fpe. I'd probably tune it for around 12-15 fpe.

I started farting around w/the KRG grips to see what I can do with them... It's looking very promising!

a guy named mike built a 30 cal and 25 cal version a few years ago. he did bypass the reg but as for porting the potential is surely there

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Weird PP700 stuff

Author Topic: Weird PP700 stuff (Read 9317 times))