VSR-SS, The Exclusively HPA Platform

Here's the physical side of things, cylinder and receiver modification.
After TONS of measuring and fitting, I have filed all excess threads from my cylinder, and have cut off the end of my cylinder.
This is so I can increase my inner barrel length, decrease weight and sound, and add a nicer bolt handle of my making.

Here's the AirsoftPro receiver I plan on using, with the cut cylinder and engine inside.
As you can see I have a piece of tape pointing at the front trigger screw hole.
I need to drill this to .265 to make way for the .260 air fitting I made.
And you can see the solenoid wiring coming out of the sear slot like usual, but I have measured, fit, and cut the cylinder so I can gain about 40mm of inner barrel by pushing everything farther back, hence the cut cylinder.

Currently I am at a standstill in terms of progress as I need to purchase material and visit my grandfather to use his shop, but I will upload pictures and explanations of my progress as I continue.

Feel free to ask questions, comment, leave suggestions, or discuss among yourselves about this as I would like to learn and see more.

Alright, so today I ended up being impatient and I drilled out the air fitting hole with a cordless drill.
I drilled undersize and filed larger, giving me a hole that isn't perfect, but perfection wouldn't affect the performance in this case.

I then made an ejection port cover/cylinder sleeve out of a cool looking can which turned out very nicely.
The AirsoftPro receiver has an ID of .986/25.04mm while the Wolverine aluminum cylinder is .942/23.95mm, making it impossible for me to use my standard soda bottle or notebook cover sleeve, so I was stuck with a soda can.
Still, I sanded all of the bumps off of my cylinder making the anodizing very shiny, and the aluminum can had a very thin plastic coating, so I assume that everything will be just dandy as there isn't going to be much friction.
Another interesting thing to note, my Wolverine cylinder comes in at .942 while my Angel Custom comes in at .951, so I expect that they made it undersize for more compatibility.
If you don't mind making a cylinder sleeve this is actually great as is will improve the weight of your gun very slightly as well as help with sound as it leaves more possible room for sound dampening materials.

I also shortened and contoured my nozzle to fit a Maple Leaf bucking quite well using a file, cordless drill, and BB covered in 40 micron lapping paste.
This improves BB placement in the buckings, aiding in accuracy.


I can't really give measurements, but you want your BB to be about .5mm onto the contact patch with the nozzle being completely inserted.


I learned this trick from the YouTuber JPSikaHunter after watching all 300-400 videos on this topic, and any shorter than this with a Maple Leaf bucking and you will see worse accuracy that originally, and as you shorten the nozzle you will see a major improvement in accuracy, the best being about at this point.

His way of testing was how many BBs out of 30 he could get onto a 320mm circular piece of metal at 50m with .96J using .30g BBs outdoors.
This is a very rough way of measuring things, but is there even a precise way to compare airsoft stuff?
Anyways, with a regular Tokyo Marui nozzle, a shimmed red Maple Leaf arm, a Maple Leaf Decepticon bucking, a 6.10 or Maple Leaf Crazy Jet depending on the age of the video, and various other modifications and upgrades he was able to get about 15-23 hits, and with the same setup but a perfect length shortened nozzle his maximum hit count was 27.
But when he used a nozzle that was too short he got a hit count even worse than stock, presumably because the BB wasn't on the contact patch yet and may have been catching on it.
Obviously this requires testing, buy I will say that you should have your BB at least .4mm onto your contact patch with a Maple Leaf bucking, and probably about that much with any other bucking.

At some point along this project I shall use the nozzle I destroyed while testing this for myself to make a new nozzle for R-hop whenever I can make a tighter barrel out of hopefully stainless steel.
This will most likely be me cutting the current nozzle down quite far and making a plastic insert with sizes and geometry a lot like a PDI nozzle, about perfect for R-hop.

Anyways, here's a playlist of the more useful videos from the before mentioned JPSikaHunter.
One thing I recommend doing before watching any of these videos is sort them by age with the little"sort by" feature, and also turn on Google translate so you can read the titles.
I also suggest that you watch these on some sort of computer as that will allow you to use auto translate, so you can actually understand the videos unless you are EXTREMELY fluent in Japanese.

Alright everybody, here's the current progress.

AirsoftPro and titanium one piece receiver heat, press, and Loctite bonded together and centered with a Delrin cylinder sleeve.
With a 5.97X590 it has about 7-8 inches of internal suppression.


Delrin hop chamber that uses O-rings instead of buckings



5.97X590 Carbon fiber/stainless barrel with a brass sleeve to fit in the chamber correctly with this here O-ring.


VSR-10 bucking for scale



The hop chamber is held in by 2 sizable fine thread stainless machine screws tapped through the titanium and hop chamber, and the BB feed hole awaiting a future feed system.


Here's the hop adjuster, a sizable fine thread grub screw threaded directly into the chamber, which presses on an SS-nub.


TBA: some more pics when it's daytime and light is better

Updates on the SS

Made a muzzle end with a press fit with 2 O-rings so I can twist side to side but have good rigidity.
Made it in 5/8-24 thread like other things as it looks cooler, and other things can fit on it like AliExpress solvent traps, the core to one of my better suppressors.


Skelly stock, with threads so I can take it off for transportation.


Brass BB tube for M14 mags


Pic of the rear screw


Pic showing the inside


Better pic of the feed ramp


Full view of the thing as of now, weighing 2550g as you see it


As you can see, I'm lacking a trigger, grip, and mag release, but that'll come later at some point.
I'm also gonna round the edges once I get the right router bit and finish making a router table.