ActionGunner
JP-5 Bolt Gap Gauge Set
JP-5 Bolt Gap Gauge Set
JP Enterprises
Maintenance · Rifle Parts & Upgrades · USPSA
SKU JP5-BGT-1020

JP-5 Bolt Gap Gauge Set

$29.95

// PROOF, NOT ADJECTIVES
Two-piece go/no-go gauge set for checking bolt gap on the JP-5. Bolt gap drifts with wear; this set tells you when it is time for a roller change. Works on MP5-pattern guns using JP’s spec.
Bolt gap is the measurement that decides whether a roller-delayed gun runs. JP calls it the most critical parts relationship in the JP-5, and it drifts as the rollers and locking surfaces wear. This two-piece go/no-go set replaces the feeler-gauge guesswork with a quick in-or-out check.
The use case is simple: the gun starts short-stroking or throwing brass differently, the shooter checks bolt gap first. If the gap has walked out of range, JP's fix is a different roller size, which is why the gauges and the roller kits belong in the same range bag.
One thing to know: JP does not publish the two gauge thicknesses on its product page, so think of the set as JP's pass/fail window for the JP-5 rather than a general-purpose gauge set. It will check an H&K MP5 the same way, since the mechanism is the same, but the window is JP's spec.
The trade-off is that a $30 tool only matters if the shooter is willing to open the gun and measure. For anyone who shoots a JP-5 in volume, it is the cheapest diagnostic they will buy.
JP-5 and MP5-pattern PCC shooters who shoot enough volume that bolt gap will migrate, and anyone troubleshooting a cycling change before swapping parts.

Out of stock

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SKU JP5-BGT-1020 Categories , , Tags , , , , , , , , , , , , Brand:
ManufacturerJP Enterprises
ModelJP-5 Bolt Gap Gauge Set
Manufacturer Part #JP5-BGT-1020
PlatformJP-5; MP5-pattern roller-delayed guns
TypeGo/no-go gauge set, 2 pieces
UseBolt gap verification and cycling diagnosis
Country of OriginUSA

Description

The JP-5 Bolt Gap Gauge Set is a pair of go/no-go gauges for checking bolt gap on the JP-5 roller-delayed carbine. JP describes bolt gap as the most critical parts relationship in the platform and recommends confirming it as the first step whenever cycling behavior changes.
Over extended use the bolt gap migrates as rollers and locking surfaces wear, which shows up as cycling problems. JP’s remedy is a change of roller size, and the gauge set tells the shooter when that point has arrived.
The gauges check the JP-5 against JP’s specification. The roller-delayed mechanism is shared with the H&K MP5, so the set functions on MP5-pattern guns as well, using JP’s pass/fail window.
What’s Included:
  • Two JP-5 bolt gap gauges (go and no-go)
What’s NOT Included:
  • Replacement rollers (see JP-5 Roller Replacement Kits)
  • Instructions for disassembly (see the JP-5 manual)
Disclosure: Action Gunner is an authorized JP Enterprises dealer and stocks this part in the Pro Shop. Product facts on this page come from JP unless noted.

RUNS WITH THIS

Pairs with: JP-5 Roller Replacement Kits (Standard, -2, -4, +2, +4), JP-5 Maintenance Kit

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