If you’ve been in the wireline game long enough, you know this job isn’t just about gear—it’s about discipline. And sometimes, a close call is the only thing that forces a lasting change. One of those moments came for me while assembling a high-shot wireline perforating string for a horizontal wireline job on a multi-stage perforation well. I watched a crew member prepping guns on the bench, and it made my stomach drop.

There were detonators crimped onto primacord, wires exposed, no sub in place—just sitting there, live, vulnerable, and ready to go if someone dropped the wrong tool or shifted the bench the wrong way.

That scene turned into one of the most important learning experiences of my career, and it’s one we’ve since embedded into all our wireline courses, procedures, and training content.

The Mistake That Almost Made the News

On this particular job, we had a high shot count: several perforating guns, preloaded with EBWs and primacord, staged and ready for assembly. The crew—good guys, skilled hands—had prepped all the guns in sequence, crimped every deto first, and left them open on the bench while moving to the next steps.

What they didn’t realize (or maybe forgot) was that even a bump from another gun, a wrench, or a slip of the hand could’ve detonated the entire string. We’re talking about explosives. Real ones. And in this case, they were armed and completely exposed.

That’s not just a violation of integrity wireline safety protocols—that’s a career-ending, possibly life-threatening hazard.

Why This Happens—and Why It Has to Stop

The practice of crimping all the detos at once and then coming back later to install the subs is about speed. That’s it. People are trying to work faster, thinking they’ll be careful. But speed without process is where wireline operations fall apart.

We’ve since discovered damaged detonators in our storage bunkers: some broken clean in half, some with crushed lead wires, some with cut insulation. The most common answer from the crew when asked what happened?

“I don’t know… maybe while downloading the gun.”

That right there is a wireline tech red flag. And it was the final push we needed to overhaul our entire gunbuilding workflow.

Our Updated Gunbuilding Best Practice

From that day forward, we implemented a new wireline services oil and gas SOP that applies to every perforating system, whether it’s a short plug-and-perf string or a high-stage cased hole wireline operation.

This is now part of our complete wireline solutions process, no exceptions:

Step-by-Step: Safe Gunbuilding Procedure

1. Start With One Gun at a Time

   • No mass crimping.

   • Each gun is completed fully—crimp, sub, EB, inspection—before the next gun is started.

2. Crimp the Detonator Safely

   • Crimp the detonator to the primacord while the carrier is partially retracted.

   • Ensure that through wires are in place and not nicked or misrouted.

3. Immediately Cover With the Sub

   • No deto is ever left exposed once it’s been crimped.

   • If a gun must be left mid-assembly, the deto must be protected or the gun must be disarmed.

4. Wire Management

   • Feed wires carefully through the sub while maintaining tension to prevent pinching.

   • Confirm proper O-ring seating and lubricate as required.

5. Scotch Locking and Testing

   • Cut all wires to proper length (typically 3–4 inches).

   • Fully insert and crimp all Scotch locks.

   • Tug-test every connection and visually inspect for nicks.

6. Second-Person Verification

   • A second crew member must verify the wiring, connections, and crimp quality before assembly continues.

7. Grounding Integration

   • Install grounding springs into each gun sub to ensure consistent continuity.

   • This is critical for eliminating switch test failures and intermittent misfires.

Why This Is More Than a Safety Rule

If you’re out there building strings for cased hole logging, cement bond logs, production logging, or even downhole pipe recovery, this process protects everything from your crew’s safety to your reputation with the client.

• Exposed detos lead to misfires.

• Misfires lead to misruns.

• Misruns lead to lost time, fishing wire line, and damaged wireline equipment.

You can’t afford that in today’s wireline services market—not when clients expect flawless execution and wireline service providers are being evaluated run-by-run.

From Missteps to Must-Have SOPs

We’ve trained every new engineer in our wireline company using this incident as a real-world case study. It’s one of the first things we teach in our wireline courses. We walk them through the risks, show them photos of damaged detos, and let them inspect bad crimps that could’ve turned deadly.

And here’s what we’ve learned:

• This isn’t just about detos—it’s about mindset.

• Rushing leads to mistakes.

• One small deviation from SOP can shut down a job or end a career.

What Is Wireline in Oil and Gas Without Control?

If someone asked me, “What is wireline in oil and gas?” I wouldn’t point to the logging cable, the pipe caliper tool, or even the wireline truck. I’d say it’s about control—control over high-risk, high-pressure environments, where precision matters and discipline saves lives.

Gunbuilding is where that control starts. Because once you’re downhole—whether you’re logging with a caliper log, running a perforating gun, or managing pressure control equipment on a tight frac schedule—it’s too late to fix what you missed on the bench.

Integrating This Into the Wireline Culture

This best practice has been adopted across all our field ops, from wireline and perforating crews to those working cased hole solutions, plug and abandon, and formation evaluation projects.

It’s part of every toolbox meeting.

It’s posted on every gunroom wall.

It’s built into our wireline logging prep sheets and our QA/QC checklists.

And it’s made us better—not just safer, but faster, because we don’t have to troubleshoot misfires or repeat runs. We get it right the first time.

Closing Thoughts – One Gun at a Time

If you’re running a crew, managing a wireline unit, or trying to scale up a new wireline business, start with your SOPs—and start with your gunbuilding.

There’s no shortcut that’s worth the risk. Not in this industry. Not with live explosives.

Because in wireline, we don’t just build guns—we build accountability.