Adding a bit longer air cylinder to PP750

Jump to latest Follow Reply
V

Vlada1911

Member
Dec 29, 2022
46
36
Belgrade, Serbia
Hello, everyone.

I've been reading forums looking for solution to this problem that probably doesn't even exist, and coudn't find anything.

So, I have modded .177 PP750 with 16 inch FX superior liner and quite a few more mods. It is now shooting JBS heavy's around 920 FPS with regulator sat around 125-130Bars.

What I would like to do is replace the air cylinder for the one with the same diameter, so I would keep original lines, but around 5 inches longer to gain few more shots.

I found one cylinder on Aliexpress with good diameter, but it is a bit longer than needed.

Does anyone know is it possible to cut the cylinder to desired length, rethread it and keep it safe?

Please check the pictures of the cylinder I found.

I'm not sure if the connections are compatible, too.

S9739658d53534805bff8dc69b9e5fd5af.jpg


S4f3d7c71d70d4d3ca173703174ef9f25q.jpg


Sb3a479b3539a4a9eb9b9051a310c1c69y.jpg
 
 
Upvote 0
Vlada1911 said:
Oh, wait, I've seen your work! Love the grips you made.
Excited to see what will come out with that cylinder.
Here is mine. Measured how much space I have to moderator- 12cm exactly. Maybe I can manage half an inch more if I get huma quick connector for moderator.

View attachment 368655
Click to expand...
Where did you get the pic rail?
 
Upvote 1
Safet22 said:
Where did you get the pic rail?
Click to expand...
I bought it localy. Its a chinese one, and not a good one. Can't be leveled so I'm looking for a better one.

All the other parts I added:
- FX superior liner 16 1/2"
- Carbon fiber shroud
- BobP's 3D printed adjustable cheek rest. He only does shipping to UK so if you are not local, better find somebody over there willing to purchase it for you and send it, like I did.
- Huma Mod 40 avalanche moderator that I protected with some thick heat shrink
- Gauge block from Wes
- CARM SSL and magazines
- Atlas clone bipod mounted on a 3d printed clamp
- Hawke 4-12x40AO scope

Looking forward to pics of yours.
 
Last edited:
  • Like
Reactions: Safet22
Upvote 0
thane said:
Won't know actual dimensions until it arrives, section and description are conflicted with 3 different dimensions called out.
Unfortunately this is common on Alibaba. May need to turn an adapter.

Dimensions should be the simplest information to communicate...
Click to expand...
And it looks like they are selling a lot of them. Not sure how, when their description is so unclear.
 
Upvote 0
Sample tube arrived at 500mm long, nothing about it measures 400 mm. Diameter is a couple mm too large.
May turn a offcenter adapter to offset tube... doesn't fix the extra 100mm.

This PP750 is going into FT Pistol duty which restricts overall length to 25", front grip depth to 3" under bore CL and entire barrel assembly to 15". Currently wood grips, LW Slow Poly 14.5" barrel with CF fitted tight on barrel and into reduces original shroud. Makes 40 shot 3/8"group at 25 yards, much improved from 8.5" barrel. Refill at shot 24 to stay under 12FPE limit, velocity increase coming off reg is severe due to small plenum volume.

The bottle drop is going to be next for a second build, pick up some plenum volume as well, see how it handles... building is almost as fun as shooting.
 
  • Like
Reactions: museguy
Upvote 0
So there is no way to use that cylinder? Bummer. I am getting around 25 good shots with 10.34 pellets shooting at around 880fps and that is with the gauge block and 16 inch FX superior liner. I was getting around 900 for the first couple of shots, but later I figured it was due to creeping regulator.
I now ordered Huma regulator, so I'm hoping to improve efficiency a bit at 900fps. I have unristricted model, but haven't done any porting.
Any advice would be appriciated.
 
  • Like
Reactions: Deadlands, thane and Raider03
Upvote 0
You must log in or register to reply here.
Top Bottom
Back
Home
Forums
Resources
Menu