To Slap or Not to Slap—Heckler & Koch's MP5

by
posted on July 28, 2017
** When you buy products through the links on our site, we may earn a commission that supports NRA's mission to protect, preserve and defend the Second Amendment. **
hk_slap_lede.jpg

It’s a little disconcerting the first time you see it. Someone jams a loaded magazine into an Heckler & Koch MP5 and then slaps the charging handle (officially called the “cocking lever”) loose from its indent notch to send the bolt slamming home on a fresh round. At first glance it seems like typical Hollywood gun abuse (in fact the silver screen is probably where you first encounter the H&K slap), like the flip of a wrist that sends the swing-out cylinder of a revolver smashing into place or the one-handed shotgun pump. But the H&K slap not only won’t damage your firearm, it’s how the factory tells you to do it.

The manual of arms for inserting a loaded magazine into an H&K roller-delayed firearm calls for the bolt to be retracted and locked into place by rotating the cocking lever into the notch in the cocking lever support housing. Inserting a loaded magazine against a closed bolt can damage the magazine’s feed lips and prevent the magazine from being properly locked into place.


Since most H&K roller-delayed firearms don’t have a bolt-hold-open device it goes like this: You fire the last round. Manually lock the bolt to the rear. Remove the empty magazine. Insert a fresh one. Then send the bolt closed on a fresh round by slapping the cocking lever out of its notch.

Why the slap? There are two reasons. First, by slapping the cocking lever out of its holding indent the bolt is going into battery with the full force of the action spring. If you ease the cocking lever out of its indent and then rotate it down to release it, you’re riding the bolt forward and beginning the process of decompressing the action spring.

The second reason for the slap is to lock the cocking lever support in place. In H&K roller-delayed firearms that tube above the barrel houses a rod that moves the bolt when pulled to the rear (remember there’s no gas system running in that tube). It’s not connected to the bolt carrier, so it’s non-reciprocating when the weapon is firing. A spring detent or catch on the front part of the cocking lever support locks it in place in the cocking lever support housing. If it doesn’t lock in place it can move back into the action during firing and potentially cause a malfunction. Again, riding the cocking lever forward can prevent the support from properly locking in place.

By slapping the cocking lever you are positively loading a round into the chamber and locking the cocking lever support firmly in place. So the next time you have your roller-delayed H&K firearm out on the range slap that cocking lever to bring the firearm back into battery. You’ll not only look cool, you’ll look like you know what you’re doing.

Additional Reading:

Roller-Delayed Revival: The Heckler & Koch SP5K
Video: The Heckler & Koch SP5K—An MP5 in Civilian Clothes 

SHOT Show 2017: Heckler & Koch SP5K Pistol  
Video: H&K MP5  

Latest

Range Ready Plinkapalooza 1
Range Ready Plinkapalooza 1

Shooting Is Fun: How I Rediscovered the Benefits of Rimfire

A recent event at Range Ready in Robert, La., reminded us how much fun the simple rimfire firearm can be, whether in handgun, carbine or rifle form.

New for 2026: Daniel Defense MUTE30Ti & NULL9Ti Suppressors

Daniel Defense was one of the first manufacturers to employ additive manufacturing techniques in suppressor-making, and now, the company has expanded its line with the MUTE30Ti and NULL9Ti silencers.

The Fight for America’s Rifle

Despite the warning we’ll sue to protect commonly owned AR-type rifles, Virginia Gov. Abigail Spanberger (D) signed Senate Bill 749, which will make it illegal to sell, purchase, import, manufacture or transfer such firearms starting on July 1. 

Gun of the Week: Henry Repeating Arms SPD Predator

The new SPD Predator, an extension of Henry's magazine-fed Lever Action Supreme Rifle design, looks to extract the greatest possible degree of accuracy and precision from a modern lever gun.

The Armed Citizen® May 15, 2026

Read today's "The Armed Citizen" entry for real stories of law-abiding citizens, past and present, who used their firearms to save lives.

The Politically Incorrect Truth About the Armed Citizen

The Second Amendment doesn’t—and should not be treated as if—it ends at state lines. American citizens need the national reciprocity legislation that is now active in Congress.

Interests



Get the best of American Rifleman delivered to your inbox.