Lantac BCG Physical

Published on March 21, 2020
Duration: 11:19

This video provides a detailed inspection of a Lantac Bolt Carrier Group (BCG) with a nickel boron finish. The instructor meticulously checks various components, including the bolt, carrier, gas rings, firing pin, and extractor, using specialized gauges and a borescope. Key findings include a smooth finish, slightly gas-inefficient dimensions, and a rounded cam pin designed to reduce receiver wear, though the instructor expresses skepticism about its effectiveness.

Quick Summary

The Lantac Bolt Carrier Group (BCG) features a nickel boron finish, a beefed-up tail for stability, and a rounded cam pin to reduce receiver wear. While its internal components show smooth machining, measurements indicate it is slightly gas-inefficient. The extractor spring design was noted as potentially weak.

Chapters

  1. 00:00Introduction to Lantac BCG
  2. 00:12Unique Design Features
  3. 00:30Venting Ports
  4. 00:42Gas Ring Test
  5. 01:05Disassembly
  6. 01:21Bolt Inspection
  7. 01:33Carrier Machining
  8. 01:56Borescope Inspection - Carrier Interior
  9. 02:14Bolt Shoulder Smoothness
  10. 02:35Gas Ring Run & Vents
  11. 03:16Carrier Bore Gauging
  12. 03:37Gas Ring Run Gauging
  13. 03:52Bolt Tail Gauging
  14. 04:16Gas Efficiency Summary
  15. 04:32Gas Key Inspection
  16. 04:53Carrier Length Measurement
  17. 05:28Bolt Inspection (Revisit)
  18. 05:32Carrier Alignment
  19. 06:06Carrier Key Screw Torque Test
  20. 06:28Overall BCG Assessment
  21. 06:43Firing Pin Inspection
  22. 07:04Firing Pin Commitment
  23. 07:09Cam Pin Tip
  24. 07:14Firing Pin Protrusion Test
  25. 07:40Ejector Inspection
  26. 07:53Bolt Face Cleanliness
  27. 08:00Firing Pin Hole Gauge
  28. 08:04Bolt Tail Gauge (Revisit)
  29. 08:18Cam Pin Fit
  30. 08:24Rounded Cam Pin Discussion
  31. 08:48Headspace Check (.223/5.56)
  32. 09:27Extractor Inspection
  33. 09:51Extractor Coating Concern
  34. 10:01Extractor Spring Design
  35. 10:18Roll Pin Check
  36. 10:22Gas Ring Appearance
  37. 11:03Overall Review & Conclusion

Frequently Asked Questions

What are the key design features of the Lantac Bolt Carrier Group?

The Lantac BCG features a nickel boron finish, a beefed-up tail to minimize carrier tilt, and a rounded cam pin designed to reduce wear on the upper receiver raceway. It also incorporates angled venting ports to redirect gas.

How does the Lantac BCG perform in terms of gas efficiency based on the inspection?

Based on go/no-go gauge measurements, the carrier bore, gas ring run, and bolt tail all measured 'yellow.' This suggests the Lantac BCG is slightly gas-inefficient, meaning it may vent more gas than a highly optimized system.

What are the findings regarding the Lantac BCG's extractor and its spring?

The extractor passed its go/no-go gauge tests. However, the instructor noted the extractor spring is a 'four coil' design, which he considers weak and potentially problematic for reliable casing extraction.

What is the significance of the rounded cam pin on the Lantac BCG?

The rounded cam pin is intended to minimize damage to the upper receiver's raceway where the cam pin resides. While a design feature, the instructor expressed skepticism about its effectiveness in preventing all wear.

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