Hey Militia, I've been getting asked more frequently about this stuff, so I figured I'd consolidate it to a single thread.
Infinity Function
The Infinity Drive is an unbalanced blowforward spool that uses the bolt itself to selectively fill the shot chamber. The bolt latching is handled by an "air sear", like most other unbalanced blowforwards. Use the diagram I put together with MacDev's photos below to help explain if needed:
Infinity Mods
1)
SFR Mod - you can adjust the vent rate of the air sear by adjusting the thickness of the seal placed in the groove. The thicker the seal, the more port area will be covered, slowing the vent rate and, ultimately, slowing the bolt's forward acceleration. The factory places a 1x17 (1mm CS, 17mm ID) seal here, which adds a
slight bit of restriction over no seal at all. If you want to run with no seal, that's perfectly acceptable. If you shoot the most fragile paint and feel the need to try slowing the down the bolt's forward acceleration a bit, that can also be done. Through testing trials, I've arrived at 3 sizes that can be run reliably:
1.5x12
1.5x13
1.5x14
REVISION: 17x1.2 and 17x1.3 are more ideally sized - same ID as the factory 17x1 so less stretch is necessary to fit, but with a 20 or 30% increase in cross sectional width. These can be purchased from TOS or if you'd rather purchase a kit from me, message me and these will be included.
I wouldn't recommend smaller than 1.5x12 due to the seal not likely surviving the stretched condition it's under, and I wouldn't recommend larger than 1.5x14 since you'll cover up too much port area, reducing cycling reliability. Every marker is different, so you may or may not have to raise the dwell by a few ms in order to return to a state of high cycling reliability. To further explain, the total cycle time of the bolt increases as you decrease the vent rate. Dwell ultimately determines the amount of time the bolt has to reach its forward-most position and stay there before the solenoid switches flow to return it to its home position. If the bolt accelerates slower, it takes longer to reach its forward position and, thus, a higher dwell time will be needed to accommodate. Without recommending everyone go through the same validation testing I do, set your dwell to 15ms and enjoy.
From left to right - factory 1x17, 1.5x12, 1.5x13, 1.5x14
2)
Volume Reduction Mod - This is a simple modification to improve efficiency by reducing the amount of air that can fit in and ultimately vent out of the shot chamber. Since the Infinity doesn't use a sensing valve to trap a partial volume of air in the chamber (like the Clone 5 drive, IV Core, Gamma, ARC, FL-21) AND is designed to dump the entire chamber every cycle, the shot chamber volume is the amount of air vented every cycle. You'll need a ~18mm long piece of 11/16" OD x 5/16" ID rubber tube and three(3) 114 orings. See the photos below on where these go.
Shown are the 3x 114 orings needed to seal off the small outer rear portion of the shot chamber:
Shown is the 11/16" OD x 5/16" ID rubber tube placed over the spring carrier:
NOTE: Wrap the cylinder in a layer of electrical tape prior to sliding the volume spacer over it. This will prevent it from sliding off while in use.
In order to make up for the loss in volume, the HPR will have to be turned up by about 15 psi (tested with a pressure tester I had made), resulting in a 115-120 psi operating pressure. As for efficiency results, I've been able to give this a full-scale (entire tank) test once using an 88ci bottle filled to a cold 4k psi. I shot 1963 shots (verified with shot counter) and was still shooting at normal velocity (280 FPS) when I ran out of paint, and the remaining tank pressure was about 300 psi. So, I could've shot an easy 2000+ shots from my 88. Correlating that to smaller bottles is easy math. Every marker is different, as is every owner - your results may vary.
UPDATE 7/7/21 - I ran another full-scale test with the XTS and same tank with the same results @ Supergame Central 2 a couple weekends ago. Still capable of shooting 2000+ with a 88ci bottle, 1800+ with a 77ci bottle.
Infinity Tips
1) Check the fitment of the bolt and inner can 019 - to do this, unscrew the can, remove the bolt, turn the bolt around and slide the rear of the bolt into the can so that it engages the 019 seal. If the fitment is loose and the bolt can just "drop" in without having to overcome any friction, the supply is never being totally isolated from the shot chamber, which will lower efficiency. Replace the 019 with a non-MacDev sourced seal or, better yet, an 019 X Ring, which will improve the fitment and longevity of that seal. Note that I have seen this condition from brand new markers.
2) Keep the front inner 017 oring clean and lubricated. This seal acts as a wiper for the bolt (as in many other spools) so it picks up any paint fuzz and contamination that gets on the bolt, which also causes that seal to experience a fairly high wear rate. An X Ring is also a good candidate here, as it seals better and lasts longer.
3) If you get a leak down the barrel, it's either a worn front inner 017 (as mentioned above) allowing the supply air to slip through OR the valve 014 that engages the bolt ID. That seal also sees some heavy loads since it has to decouple from the bolt every cycle in order to dump the chamber. Keep it well lubed and take note of how it fits the bolt (there should be some resistance, but not a lot) and you'll be good to go.
4) Speaking of lube, the only bolt seals that need it are the 16x2 bolt sail (a 016 and 16x2 are not the same, FYI), inner can 017 and 019, and valve 014. Nothing else needs lube and the outer static seals just need residual from your fingers.
5) Toss a 018 or 019 oring on the barrel back in front of the threads - this is a nice fit for a friction seal against the body
6) Take note with how the grips seat into the frame - the area behind the trigger, along the body, and along the rear vertical edge of the frame should all seat flush inside the frame grooves, but it may take a little manipulation to get it all to fit perfectly. The rear lower corner that mates against the back of the ASA should also seat nicely in the frame groove. I've seen a lot of owners pay little attention to this and it looks sloppy and doesn't protect against water and contaminants from entering as designed.
7) The trigger can either be incredibly amazing or bad depending on how it's adjusted. I'll assume you know how to properly adjust and setup a trigger, but if you need more details just ask and I can walk you through how I do it. On that note, the trigger system (carrier + components) design of the Prime/XTS is really damn good.
8) I like to drop a 2x3 oring into the spring carrier (the piece the spring slides into) in order to firm up the back cap action even further. It gives it the nicest feeling "bolt action" feel of any back cap on the market.
9) Ensure you're running software revision 1.20 - I cannot stress this enough. The previous versions have a flaw in the eye logic and BPS cap logic, potentially resulting in skipped shots, chops, and/or cap penalties. I validated 1.20 for Bourke and can confirm that it is correct under all conditions, in all modes.
SEAL REVISION: I've been running cast urethane in the 014 valve and 017 inner can locations, and standard urethane in the 019 inner location and would recommend this as my top choice for the Infinity and C5 drives. Please note that you DO NOT want cast urethane in the 019 location, as the fitment is too loose, which will cause inefficiency.
Cast: https://www.theoringstore.com/store/...=367_1321_1323
Standard 019: https://www.theoringstore.com/store/...ducts_id=16053
Seals:
https://www.theoringstore.com/store/
Rubber tube and anything else you could ever need:
https://www.mcmaster.com/
Disclaimer: I am not a MacDev employee and if I were, I would be more cautious about posting modifications like this. But I'm not, so have it you filthy animals. Additionally, I am in no way responsible if you do something stupid and break your marker.
MILITIA!
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