Best for: Woodsball, Field rentals, Tinkerers who want a platform
Setup & First-Day Tuning Guide
Inspect Cup Seal & Fittings Before Air — Before adding air to the Tippmann 98 Custom Platinum Series ACT, inspect the cup seal inside the valve and all macro-line fittings. The cup seal is the #1 failure point on mechanical guns. Replace if cracked or flat — they cost under $5.
Attach Air Source Slowly — Thread on your HPA tank or CO2 tank slowly. Listen at all connections for leaks. HPA is strongly recommended over CO2 for consistency and long-term seal health.
Install Barrel & Loader — Attach barrel and loader before loading paint. A gravity hopper works at 5–6 BPS. An agitating loader prevents jams and is worthwhile at any price point.
Chronograph & Adjust Velocity Screw — Fire 10 shots across the chrono. Adjust the Tippmann 98 Custom Platinum Series ACT's velocity screw clockwise to raise, counter-clockwise to lower. Quarter-turn increments. Target your field limit (usually 280 fps).
Shoot 20 Break-In Shots, Then Re-Chrono — Mechanical blowbacks often run 5–10 fps high for the first 20 shots as the cup seal seats. Re-check after break-in and make a final adjustment.
CO2 Rate-of-Fire Warning — On CO2, keep rate of fire under 6–7 BPS. Faster pulls liquid CO2 through the valve causing freeze-ups and seal damage. HPA eliminates this entirely.
Maintenance Schedule
Interval
Task
Detail
After every outing
Barrel, bolt & exterior clean
Squeegee twice, bolt wipe, screws snug.
Every 5 sessions
Bolt O-ring lube & cup seal check
Clean with isopropyl, dry, apply Dow 33. Inspect cup seal — replace if deformed.
Every 6 months
Valve & fitting service
Re-lube all O-rings. Check all fittings and inline regulator if present.
Annually
Full teardown & O-ring replacement
Complete disassembly, full O-ring kit replacement, inspect springs.
Split receiver opens with screws for full internal access; very serviceable.
Common Problems & Troubleshooting
Velocity drops mid-play
Cause: Worn cup seal; CO2 liquid pull; low pressure
Fix: Inspect cup seal first. On CO2, slow your ROF. Try a fresh tank fill.
Bolt doesn't return after firing
Cause: Broken hammer return spring
Fix: Disassemble the Tippmann 98 Custom Platinum Series ACT and inspect the hammer spring. Replace with an OEM spring — they cost under $10.
Ball breaks in barrel (chops)
Cause: Worn detent; hopper not keeping up
Fix: Check the ball detent. If shooting over 6 BPS with a gravity hopper, upgrade to an agitating loader.
Air leaks from barrel
Cause: Worn cup seal
Fix: Replace the cup seal — this fixes barrel leaks in 90% of mechanical blowback guns. Part costs under $3.
Air leaks from grip area
Cause: Valve body O-ring failure
Fix: Apply Dow 33 to the valve body O-ring. Also check all macro-line compression fittings.
Upgrade Path
Response trigger / e-grip
Flatline or rifled barrel
Cyclone feed
Stock/shroud kits
Frequently Asked Questions
Is the Tippmann 98 Custom Platinum Series ACT good for beginners?
Yes — the Tippmann 98 Custom Platinum Series ACT is an excellent first-time gun. It's durable and forgiving of beginner mistakes.
Does the Tippmann 98 Custom Platinum Series ACT run on CO2 or HPA?
Compatible with HPA/CO2. CO2 works but HPA gives significantly more consistent velocity and is better for long-term seal health.
What is the operating pressure of the Tippmann 98 Custom Platinum Series ACT?
The Tippmann 98 Custom Platinum Series ACT operates at ~250 psi. Match your regulator output to this spec.
How hard is the Tippmann 98 Custom Platinum Series ACT to maintain?
Easy — basic bolt cleaning every few sessions. Split receiver opens with screws for full internal access; very serviceable.
What loader does the Tippmann 98 Custom Platinum Series ACT need?
A standard 200-round hopper works. An agitating loader prevents jams at higher rates of fire.
How much does the Tippmann 98 Custom Platinum Series ACT cost?
New: $100 MSRP, typically $110-160 on the street. Used prices vary — check BST forums and eBay for current asking prices.
What barrel thread does the Tippmann 98 Custom Platinum Series ACT use?
The Tippmann 98 Custom Platinum Series ACT shoots .68 caliber. Confirm the specific thread pattern for your variant before ordering a barrel.
What firing modes does the Tippmann 98 Custom Platinum Series ACT support?
Supported modes: semi-auto. Most recreational fields require semi-auto only.
How heavy is the Tippmann 98 Custom Platinum Series ACT?
3 lbs unloaded. With a full hopper and HPA tank, expect roughly 5.5–6.5 lbs total.
Is the Tippmann 98 Custom Platinum Series ACT worth buying?
The genre's workhorse for two decades: a split-receiver blowback with an Anti-Chop Technology bolt and a vast aftermarket and field-rental footprint. Strengths: Massive parts/upgrade availability, Easy to service. Trade-offs: Dated ergonomics, Needs upgrades to modernize.