First announced at the 2026 SHOT Show, Rifle Builder PRO has transitioned rapidly from a PowerPoint mockup into a fully functional internal beta web application. In this video update and live demonstration, Gavin Gear walks through how the software handles live cartridge data, action dimensions, on-the-fly math, and step-by-step lathe machining—demonstrated during a real 6.8 Western custom rifle build. Check it out!

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From Concept to Reality: The Evolution of Rifle Builder Pro 

Rifle Builder Pro was born out of a desire to eliminate manual, error-prone calculations at the lathe. After successfully testing the core mathematical workflows on manual iPad setups during previous custom rifle builds (such as the 7mm PRC medium-action build), development accelerated into a fully functional local web application. 

Core Features and Live Demonstration 

Running locally during the internal beta stage before a cloud deployment, Rifle Builder Pro simplifies every phase of chambering and barrel fitting:

• Interactive Cartridge Database: Integrates comprehensive SAAMI specification data. Gunsmiths can instantly view cartridge dimensions in inches or millimeters and compute values on the fly, offering a massive upgrade over static SAAMI diagrams.
• Action Selection & Scale Drawings: Users select specific rifle actions (such as the BAT Machine Igniter short and long actions). Unlike static scale diagrams, the app renders thread specs, tenon lengths, diameters, and chambers completely to scale, dynamically converting between inches and metric units.
• User Preferences & Automated Math: Custom preferences allow gunsmiths to configure stop-short distances, under-drill diameters, and threading infeed angles. The app automatically calculates critical metrics like end-play clearance (such as BAT’s 0.008″ spec between the tenon and bolt lugs).
• Step-by-Step Lathe Guidance: The interface guides the gunsmith through each sequential operation using clear color-coded indicators (red cuts, blue notes) matched directly to digital readout (DRO) values:
  • Pre-Drill Selection: Automatically cross-references a 115-piece drill index (fractional, numbered, and lettered bits) to select the closest drill diameter equal to or less than the target size.
  • Throat Dial-In & Boring: Assists with precision dial-in points and optional boring of the lands.
  • Tenon Turning & Thread Relief: Automatically accounts for cleanup passes (e.g., leaving 0.002″ during turning before cutting the thread relief).
  • Threading, Chambering, and Headspacing: Provides real-time guidance through threading, reamer plunging, and depth verification using go/no-go gauges and precision micrometers.

Current Status and What’s Next

While the internal beta is fully functional end-to-end for basic chambering work (as proven on the 6.8 Western build), active development is expanding to cover advanced configurations, including counterbored barrel tenons with protruding bolt noses (like Remington 700-style designs), cone breaches, and unthreaded bearing surfaces.

Following ongoing cartridge and action additions, a limited public beta will launch with a select group of 5 to 10 industry professionals, independent gunsmiths, and instructors to co-engineer features and gather real-world feedback.

Conclusion

Rifle Builder Pro promises to be a game-changer for both aspiring and professional gunsmiths, bringing unprecedented efficiency, accuracy, and ease of use to precision rifle manufacturing.

If you want to follow the development, sign up for updates, or apply to have your manufacturing products (actions, barrels, muzzle brakes) integrated into the platform, visit riflebuilderpro.com.

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Thanks,
Gavin Gear