The HollowPoint Ion bolt with HollowValving™ and Anti-Roll-Back (ARB™) is a unique bolt system for the Ion, but installation and tuning is fairly simple.

The HP Ion bolt kit includes:
1x gold Bolt
1x black Stalk
1x large black thin ring
1x short screw
1x #010 BN70 tail seal O-ring
1x #015 PU90 main valve O-ring (lube)
1x 1.5x17mm BN70 sail O-ring (lube)
1x 1x16mm BN70 bumper O-ring

Installation of the HP Ion bolt kit:
1) Remove the existing bolt and chamber divider disk from your Ion. In the pictures, we show the tail air-donut removed from the firecan-- this is not typical on a stock Ion unless you have a BOB™ body.

2) Lube the bolt sail O-ring and stalk valve O-ring with Ion/Shocker/SP lube. The stalk O-ring is close to undersized to start with. This is because it will expand slightly from the lube. If you experience leaks at first, you can try removing the stalk O-ring and lightly stretching it with your fingers first to prevent any initial leaking.

2) Install the large thin ring into the firecan. this will take the place of the stock Ion chamber divider disk. The large thin ring will go in either way, but ONLY ONE WAY IS CORRECT. Install so that the internal "lip" is facing forward, away from the firecan. This large thin ring is not 100% critical. If left out, the bolt kit will still work fine, but probably not as effective. If the ring is installed backwards, it will decrease the performance by restricting flow.

3) Remove the short screw from the tail of the HP bolt stalk and slide the bolt stalk into the Ion firecan.

4) Push the bolt stalk all the way into the firecan and install the short screw with O-ring in from the tail of the firecan. It is a good idea to apply some LocTite to this screw before putting it in, otherwise it could back out from the vibrations of shooting. We have found that red loctite seems to work good. To tighten the screw, grip the firecan like a grenade, push down on the tip of the bolt stalk with your thumb to hold it in and prevent it from turning, and tighten the short screw with an 5/32" Allen wrench with your other hand. It should be tight, but do not go overboard with force.

5) After the short screw is tightened, make sure that the bolt stalk is centered by performing a "roll test". Lay the firecan on a flat surface and roll it. If the tip of the bolt stalk does not roll steady in the center, push it sideways in the direction it needs to go to center it. Using this method the bolt stalk should be able to be nudged to the center if it is not already there. If the bolt stalk is not centered, performance will be degraded and abnormal wear will occur on the components, as well as possible leaking down the barrel.

6) Slip the bolt into the firecan, large end first.

7) Re-assemble the Ion as normal. When done, the bolt tip and ARB™ top should be up to the edge of the feedneck hole.

"How it works":
Here are some cutaway views of the bolt (without the bumper O-ring). Notice that at rest the ball cannot roll back into the deep cup face of the bolt. A ball that starts in the same place every time has a better chance of being shot more consistently. Also, if a ball is allowed to roll back into the cup face of a bolt, the next ball in the stack above it can be pushed down slightly in front of the ball, so when shot, can cause ball breaks and inconsistent shots.

As the bolt moves forward, it cradles the ball with the deep cup face and minimizes "ball-stack-bobble". "ball-stack-bobble" is when there is a gap between the ball being chambered and the lip of the bolt. A gap here gives the next ball in the stack a place to blip down into between the ball and the bolt lip and can cause ball breaks and interfere with the bolt travel, causing inconsistent shots.

Near the end of the bolt stroke, the O-ring on the bolt stalk exits the bore inside the bolt and allows the air in the firechamber to flow forward through the bolt. The HollowPoint is designed to try to maintain air flow consistency through the bolt for an efficient shot.

Tuning procedure:
The goal with this and any other Ion bolt is to run the lowest dwell without getting low and inconsistent velocity. If the dwell is way too high, you will see very stable velocity but the marker will use lots of air per shot. If the dwell is too low, air is not wasted, but the bolt will start returning before the ball is up to full velocity, causing low and inconsistent shots.

Different Ion boards use the word "Dwell" differently. The stock Ion board starts at a base dwell number and allows you to adjust up from there in increments of 1/2 ms. Aftermarket boards may or may not start at a base dwell, and most will increment in 1ms, or change from 1/4, 1/2, or to 1 depending on how large the number is. If you use a QEV your dwell could be 2x to 5x times lower than without a QEV. A fresh battery will make the solenoid more snappy and will operate differently than when using a weaker battery.

Dwell- Because of all of the variations listed above, there is no "one correct dwell". You will need to find your dwell and go from there. The typical advise is to start low and go up until your velocity no longer substantially increases, and then add a couple more for a safety zone. Dry-firing tells very little... you will need to test with paint and a chrono.

Pressure- Start around 130 psi and go from there to get your desired velocity.

Pressure/Dwell relation- The higher your pressure, the slightly lower you can run your dwell. This setup can give better efficiency, but will be harder to keep consistent. This combo is also harder on paint and can cause ball breaks if the pressure is too high.

What we tested-
Without QEV: 300fps @ 150psi, 26-30 dwell flashes on a stock Ion board (physical dwell of 21 to 23 ms).
With Clippard QEV: 300fps @ 150psi, 0-4 dwell flashes on a stock Ion board (physical dwell of 8 to 10 ms).

Troubleshooting:
- There is air leaking down the barrel:
i. Try gassing it up quickly at first. The o-ring in the valve might need to "fly out" to seat in. Or try firing a few times-- this will let the valve seal to re-set.
ii. Check the nose and inside rear part of the bolt for scratches and/or debris.
iii. Make sure the nose of the bolt stalk is close to centered in step 5 above.
iiii (or is that iv?). Check/replace the bolt stalk O-ring. If it is old, try replacing it. If it is new, it might need to be lightly stretched first (step #2 above).

- After shooting for a while, paint no longer wants to feed into the breach:
i. This is usually caused from the stalk rear screw backing out from the bolt stalk. To check for this simply pull your hopper off and look down the feedneck. If the bolt tip is protruding into the breach (it should be flush with the feedneck back edge), then check the rear stalk screw. Add LocTite to the screw if needed to prevent it backing out again.