HK/PTR91: To slap or not to slap?

[Richard Erichsen]

With out the cartridge being stripped slowing the action down and then chambered acting as a cushion your slamming the bolt and trunnion together at full speed and that can't be good and isn't. Think before let fly with your not so expert advice.

If you presume the bolt face were actually able to touch anything, it would be the barrel breech face which stands "proud" of the trunnion. I asked the same questions about a year ago over on Militaryfirearm.com where a good chunk of the builders of DRB actions congregate. On new rifles, including rifles built from parts kit, contact will not be occurring if the rifle is built properly.

R

[Richard Erichsen]

if you want to be quick with your reloads, try loading one less, 9 or 19 so the cartridge doesn't get crushed and or cause resistance, load on a closed bolt and then cylce the action but don't lock the charging handle so you won't have to waste time, at least slapping it is quick though but I think that gets old unless its something you like to do.

Or better yet, don't run it dry, count your rounds and do a mag change so you don't have to pull back on that heavy spring.

Just some ideas.

I'm not clear on what above means at all. How exactly does a round get "crushed" and what are you gaining by 'not' locking back the charging handle before inserting the magazine?

R

[kurac]

I'm not clear on what above means at all. How exactly does a round get "crushed" and what are you gaining by 'not' locking back the charging handle before inserting the magazine?

R

typically when you try to seat a full magazine on a closed bolt, the top round on the magazine will get crushed somewhat on the bolt carrier, sometimes you can't even seat a fully loaded magazine on a closed bolt, it depends on how much give there is. If you take a round out of your full magazine, then there will be some give so you don't crush a cartridge thus allowing you to easily seat a magazine. This is why people are locking the bolt back to insert a fresh magazine in the first place.

[NSR500]

Slap the **** out of it.

[FMJBT]

Slap when chambering a round, otherwise I'd suggest riding the handle forward for the sake of the bolt face and breech. On an empty chamber, the bolt face WILL contact the breech. Absolutely, every time. The bolt coming to a positive stop against the breech is what determines the bolt gap (Space between the carrier and bolt head during lockup). Bolt gap is ALWAYS measured on an empty chamber as the Delayed Roller Locking design uses a short chamber. With a cartridge seated in the chamber, the bolt gap will be significantly larger, and will vary from one round to the next depending on brass size. With a cartridge in the chamber, only then will the bolt face NOT contact the breech under lockup. There should be a gap of approximately .009" between the bolt face and breech, again this will vary depending upon the length of the brass.

[Richard Erichsen]

Slap when chambering a round, otherwise I'd suggest riding the handle forward for the sake of the bolt face and breech. On an empty chamber, the bolt face WILL contact the breech. Absolutely, every time. The bolt coming to a positive stop against the breech is what determines the bolt gap (Space between the carrier and bolt head during lockup). Bolt gap is ALWAYS measured on an empty chamber as the Delayed Roller Locking design uses a short chamber. With a cartridge seated in the chamber, the bolt gap will be significantly larger, and will vary from one round to the next depending on brass size. With a cartridge in the chamber, only then will the bolt face NOT contact the breech under lockup. There should be a gap of approximately .009" between the bolt face and breech, again this will vary depending upon the length of the brass.

I was mistaken. The bolt DOES come into contact with the barrel breech face, however, when I asked some of the long time owners and builders over on Militaryfirearm, the answer on whether this was important or not was it would take many tens of thousands of cycles to cause much in the way of measurable wear. It was mentioned shooting primarily .308 Win cartridges would cause more wear than just dropping the bolt on an empty chamber due to the shorter case of the .308 cartridge than that of 7.62 NATO cartridge (even if the average amount of length difference is only about .002"). Those on the MF board are far more picky about ammo worried about bolt face meeting barrel breech and not so worried about dropping the bolt on an empty chamber.

I was also reminded by this exchange that the exact same thing happens when you fire until the magazine is empty. Whether you drop the bolt manually or the weapon cycles onto an empty chamber, the effect is the same. Actual wear caused by either method that cause the bolt to lock on an empty chamber is probably not worth worrying about.

R

[chead]

Yeah I mean it's not going to break your gun immediately. If you have an original HK worth several thousand, you might consider not slapping it empty. Or just
if you want to be extra nice to your clone.

[West coast]

Slap it....

[pyro3k2]

I say don't slap it, and not for the normal "don't do it." reasons

I find it to be much faster after reloads to catch the charging handle between the webbing of my thumb and pointer finger and to roll the charging handle down. After the bolt is sent home Your support hand will naturally find your preferred grip on the rifle either the mag-well grip or extended on the hand guard. You will cut a lot of movements out of your reloads that way and find yourself back on target sooner. Granted it doesn't look as cool and is not as flashy but I like results more than looks. Also it's a hell of a lot faster if you happen to miss the charging handle on the first slap (it's ok we are among friends, everyone has missed an HK slap...EVERYONE)

[technique]

I slap the **** out of MP5 and MP5-40s...
Slap away.

Or, ya know, gently ride it forward on your freshly cleaned precious.
Whatever floats your boat.

[Richard Erichsen]

I slap the **** out of MP5 and MP5-40s...
Slap away.

Or, ya know, gently ride it forward on your freshly cleaned precious.
Whatever floats your boat.

<Gollum voice> "We do not slaps upon the PRECIOUS! Not the PRECIOUS!! </Gollum voice>

[someR1]

what did the 5 fingers say to the face ??

SLAP !!

[Holescreek]

I don't slap mine but every now and again I give it a little tap on the butt to let it know I like it.

[seainc]

HK SLAP http://www.hkpro.com/forum/hk-nfa-ta...tml#post551114

[nimoZ]

I don't slap mine but every now and again I give it a little tap on the butt to let it know I like it.

- God one


- I was told to always slap by my Srgnt. You don't want to get caught with gloves etc or slow feed a round with dirt build up.
This was with well used rifles that get re-issued every year with little to no TLC.

I would not worry about it.