Based on the SOPMOD designed bolt upgrade and rebuild package, this kit is designed to breathe new life into your bolt assembly. The bolt assembly is the heart of your AR15 rifle system and preventative maintenance used by professions insures these systems keep running even under the harshest of conditions. This is a great spare parts kit to keep your AR15, M16, M4 running in the field.
This kit includes:
- Extractor made to USGI specs (shot peened)
- Extractor pin
- BCM® Extractor Spring (chrome silicon, heat treated & stress relieved, shot peened)
- 3 USGI Gas Rings
- Crane Ind O-Ring (Mil-Spec)
- Black Extractor Insert
If you’re looking to refresh a high-performance bolt or revive a "retired" one, the Bravo Company Manufacturing (BCM) SOPMOD Bolt Upgrade Rebuild Kit is essentially the gold standard for reliability.
This kit isn't just a bag of spare parts; it’s a specific collection of components designed to increase the extraction tension and service life of an AR-15 bolt, following the "SOPMOD" (Special Operations Peculiar Modification) specifications.
What’s Included in the Kit
The kit focuses on the "weak points" of the bolt assembly—specifically extraction and gas sealing.
- BCM Extractor Spring: A heavy-duty, chrome silicon spring that maintains tension longer than standard springs.
- Black Extractor Insert: A crane-spec polymer insert that sits inside the spring to prevent it from buckling.
- O-Ring (Viton): An extra layer of insurance that increases extraction force (often used in shorter gas systems like Carbine or Pistol lengths).
- Gas Rings (3): Three high-quality stainless steel rings to ensure a tight seal within the carrier.
- Extractor Pin: A fresh pin, as these can sometimes shear or bend under high round counts.
Why Use This Kit?
Standard mil-spec extractor springs can weaken over time, leading to "failures to extract" (FTE). This kit addresses that in three ways:
- Increased Tension: The combo of the heavy-duty spring and the O-ring ensures the extractor claw grips the casing rim with much more authority.
- Reliability in Short Barrels: Short-barreled rifles (SBRs) have higher port pressures. The SOPMOD upgrades help the extractor hold on during the more violent extraction cycle.
- Preventative Maintenance: It is generally recommended to replace these components every 3,000 to 5,000 rounds to ensure the rifle remains "duty-ready."
Installation Tips
- The O-Ring Choice: You don't have to use the Viton O-ring if your rifle is already extracting perfectly. Some users find that using both the heavy spring and the O-ring makes the extractor so stiff it’s difficult to snap over the rim of the cartridge. If you have a 16-inch Mid-length system, the spring and insert are usually plenty.
- Stagger the Rings: When installing the three gas rings, ensure the gaps are not aligned. Space them roughly 120 degrees apart to prevent gas leakage.
Comparison Table: Standard vs. SOPMOD
| Feature | Standard Mil-Spec | BCM SOPMOD Kit |
| Spring Material | Music Wire / Standard Steel | Chrome Silicon (Heat Resistant) |
| Insert Color | Blue or Black | Enhanced Black |
| O-Ring | Usually Absent | Included (Viton) |
| Expected Life | ~3,000 Rounds | 5,000+ Rounds |
