TGB-TI-001 — AR-15 Carrier Timing
Question
What does “delayed unlocking” actually mean in an AR-15, and which carrier designs demonstrably change the timing of the events that matter?
TGB-TI-001 compares four carrier architectures:
- conventional / TDP-pattern carrier;
- Leitner-Wise Gen 2 Long Advance carrier;
- LMT Enhanced carrier;
- SureFire Optimized Bolt Carrier.
Why this investigation exists
Public discussion often treats the following as though they were the same thing:
- initial carrier movement;
- first bolt rotation;
- rate of bolt rotation;
- complete lug clearance;
- carrier exhaust-port exposure;
- initial extraction;
- chamber pressure at unlocking;
- total rearward stroke.
They are not the same event.
TGB therefore compares event position and event timing, not the generic phrase “more dwell.”
Current mechanism model
The useful operating sequence is:
gas actuation → carrier motion → initial bolt rotation → progressive rotation → complete lug clearance → extraction
Carrier vent exposure is tracked separately because it can occur on its own geometry-dependent timeline.
Evidence method
TGB distinguishes among:
- OBS — Direct observation;
- MFG — Manufacturer claim;
- PRI — Primary technical documentation;
- PAT — Patent / design evidence;
- IND-M — Independent measurement;
- IND-R — Independently reproduced result;
- INF — Inference;
- HYP — Hypothesis;
- UNK — Unresolved uncertainty.
A patent establishes claimed architecture and design intent; it does not automatically prove current production geometry or measured performance.
A manufacturer performance claim remains a manufacturer claim unless supporting measurement evidence is available.
Current high-value uncertainty
For the current-production Leitner-Wise / VKTR Gen 2 Long Advance carrier:
How far does the carrier move rearward from the fully locked/battery position before the bolt first begins to rotate?
That one production-derived dimension would materially improve the comparison because the patent clearly establishes altered cam geometry and a 22.5° rotational objective, but that does not by itself prove additional battery-referenced locked carrier travel.
What would resolve it
The minimum useful evidence would be:
- a current-production carrier-travel dimension from battery to first bolt rotation;
- preferably the equivalent dimension for a conventional/TDP carrier using the same datum.
Stronger evidence would include a dimensioned current-production cam profile or bolt-angle-versus-carrier-position data.
Current status
ACTIVE — current-production Gen 2 battery-to-first-rotation travel remains unresolved.
No production-wide timing conclusion is assigned until stronger evidence resolves that hinge.
TGB will update its conclusions if better evidence changes the model.