Chapter 0 — Start Here

First 100 Rounds with Borely

The most valuable data Borely will ever hold for your barrel is the data from your first 100 rounds. Not because those rounds are the most interesting — early barrel performance is often inconsistent as the throat settles — but because they establish the baseline everything else is measured against.

Before You Fire the First Round

Setup starts before the first shot. In Borely, create your caliber first, then your barrel. Give it a name you will recognize in two years (“6.5 CM Match #1” beats “barrel1”). Set an estimated life in rounds — 1,500 for a 6.5 Creedmoor is a reasonable middle estimate, though your actual results depend on load, heat management, and powder choice.

Add your primary load to the load library with every detail you have: bullet, powder, charge, primer, brass, COAL, and CBTO if you have measured it. Before your first session, measure your CBTO-to-lands distance using a Hornady OAL gauge or similar tool, then record with your comparator and caliper — noting exactly which tools you used. This is your throat baseline.

Track this in Borely
Borely is the iOS app built for exactly this — logging round counts, sessions, CBTO readings, and load data so your data story writes itself.
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Sessions 1–3: Break-In and Baseline

Whether you run a formal break-in protocol is a separate debate, but the first three sessions are your baseline establishment period regardless. Log in each session:

Rounds 50–100: First CBTO Check

At approximately 50 rounds, take your first post-baseline CBTO measurement. Use the same comparator and caliper you used on day one — the same insert, the same caliper, no exceptions. Record it in Borely’s Lands tab.

You are unlikely to see significant throat movement this early, but this gives you a second data point. Two points define a line — the beginning of your erosion trend. Every subsequent reading adds resolution to that trend.

At 100 rounds, review what you have: a velocity baseline, an ES/SD baseline, a throat baseline, and a cleaning history. This is your Day Zero data package.

What good looks like at 100 rounds

Velocity stable within ±15 fps of your baseline. ES under 20 fps for a well-developed load. CBTO showing minimal movement from your original measurement.

The Habit That Pays Off Later

The single most important thing Borely can do for you is make session logging effortless enough that you actually do it. Logging a session — selecting your load, entering velocity, adding conditions — takes under a minute. The payoff is asymmetric: a minute of logging per session compounds into years of diagnostic intelligence.

When your barrel shows signs of wear at round 1,200, you will know whether velocity has dropped 25 fps or 5 fps. You will know your cleaning intervals and whether they have changed. You will know where your throat was at round 100 versus where it is now. None of that exists without the habit, and the habit starts in the first 100 rounds.

Recommended Tools
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Garmin Xero C1 Pro Chronograph
Doppler radar chronograph — no barrel attachment, no effect on harmonics. Works with suppressors and muzzle devices. The current standard.
Athlon Rangecraft Velocity Pro Radar Chronograph
Doppler radar, no barrel mount. 65–5,000 fps range, IP67 waterproof, USB-C charging. Tested within 0.6% of Garmin units. Strong value at ~$399.
Hornady Lock-N-Load OAL Gauge
Standard tool for measuring bullet-to-lands distance to establish your initial CBTO baseline.
Mitutoyo 500-196-30 Caliper
Designate one caliper for this barrel. The Mitutoyo is the standard for repeatable precision measurement.
Sources & Further Reading