https://www.hkpro.com/threads/hk-steel.535502/

 

Is this just marketing

No, it's not.

It's a combination of steel used, manufacturing method and heat treating method plus chrome lining.

 

"The highest quality steel is used in this unique manufacturing process producing a barrel that provides superior accuracy for more than 20,000 rounds with minimal degradation of accuracy and muzzle velocity. HK416 variants are available with multiple barrel lengths (see product list)."
considering most barrels start to lose accuracy after 4 or 5k rounds.

not in my experience - my M1A has 30k+ rounds and still shoots 1 MOA - accuracy at over 500m suffers but for 200m it is still more than good enough for me.

 

"The highest quality steel is used in this unique manufacturing process producing a barrel that provides superior accuracy for more than 20,000 rounds with minimal degradation of accuracy and muzzle velocity. HK416 variants are available with multiple barrel lengths (see product list)."

Is this just marketing, or am I misreading this and it's saying the barrel can go 20k rounds before its no longer usable. considering most barrels start to lose accuracy after 4 or 5k rounds.

The barrel can go 20,000 rounds with minimal degradation of accuracy. The 416 barrel (like all HK barrels) can go much further than 20,000 rounds.

 

There is an article out there written by a Police Officer in Northern VA, I think Fairfax Co. Police Dept. who shot his upper for somewhere around 67k rounds without key-holing.

 

Canipe Correspondence - Retiring My 416 | Soldier Systems Daily

 

Canipe Correspondence - Retiring My 416 | Soldier Systems Daily

You snipped it at the most important part:

Today, I’d be lying if I told you the barrel was in good shape. It’s a solid 4 MOA with 77GR MK262 now, and is experiencing some velocity loss.

He claims to still print a ~4" group at 100 yards, but velocity loss = hotdog down a hallway.

Hooray for HK and all that, but there is simply no reason to keep a barrel and keep using a barrel to the point where you are experiencing velocity loss.*

*well, there might be a reason- You suck, and HK hates you, and you can't simply purchase a replacement (416 barrel) when your barrel is beyond it's servicable life.

I can wear my shoes until my heel touches the ground (almost did with the pair of boat shoes I just retired), but I don't need to go through the gum sole (accuracy loss) and then keep on wearing them until I go through the leather (velocity loss). Now, the problem is that a new pair of Gold Cups is now $100 cheaper, and feels $200 cheaper than the last pair... so I guess I suck and Sperry hates me.

 

HK barrels have a very long service life, as not only the bore but also the chamber is cold hammer forged. Both the barrel and the chamber are also chrome lined.
Another special feature is that the diameter of the bore becomes slightly smaller near the muzzle, which increases accuracy, similar to the choke of a shotgun. This is also the reason why there were problems with the firearms office in Ulm, as this is not CIP compliant.

An HK employee I know told me that an HK416 they had in the factory with a round count of 50,000 was tested for accuracy and it still achieved a grouping of a 2 € piece (~ 26 mm = 1 inch) at 100 meters.

 

Another special feature is that the diameter of the bore becomes slightly smaller near the muzzle, which increases accuracy, similar to the choke of a shotgun.

This is absolutely incorrect.

The 416 barrels from 2004 to mid 2008 had a tapered bore that comprised the first inch or so of the bore just past the chamber. This is why standard M16/M4 barrel gauges would not accurately gauge HK 416s. The remainder of the bore had zero taper, contradictory to wifes tales and popular belief. I know this because i gauged the bores of several 416s and MR556s to not only ascertain bore taper, butfind the difference of bore internal diameter between actual 416's and MR556s.

Sometime in 2008, HK eliminated the tapered bore feature entirely due to lead residue blowback issues into the shooters face due to a series of tests that were done that proved excess lead exposure when shooting suppressed that was found to be exacerbated by the tapered bore.

From mid-ish 2008 to present, HK416 bores are no longer tapered. And have never been tapered beyond the short taper just past the bore on the early guns from the 2004 through 2008 models. It is absolute fallacy that the bore tapers anywhere near the gas port or muzzle in ANY year of 416 manufacture.

I have worked on a very large amount of 416s across a wide range of years worth of manufacture, and still do on a regular basis. While we use dedicated HK manufactured gauging, standard M4 gauging can now be used if necessary fue to the removal of the tapered bore. Well, except firing pun protrusion. All HK guns will "fail" M4 firing pin protrusion gauging. A proprietary 416 firing pin gauge must be used. Nore does the firing pin hole gauge for the bolt face in the standard M4 gauge kit work either. The HK gauge kit doesn't even have a firing pin hole gauge for the bolt face, not does it have a fire control pin gauge.

 

I have put about 25k more rounds in my trade in 416 upper that I got cheap because it was very beat up and now it still hold up. HK barrel quality really is another level.

 

MR223 bores are still tapered.

This is the reason why they are currently not proofed by the Ulm proofhouse (branch in Oberndorf, that is), but in Birmingham. The Birmingham proof house even marks the lesser diameter:

There is an ongoing legal battle between HKO and the Ulm Proofhouse (it seems that it quieted down recently, though) about the allegedly non-CIP-compliant bore profile that is "slightly tapered at the muzzle":

Heckler & Koch streitet mit Waffen-TÜV - WELT

Prüfer verweigern für einige zivile Gewehre den Freigabestempel. Beim bizarr anmutenden Konflikt geht es um nur wenige Hundertstel Millimeter

www.welt.de

Verwaltungsgericht: Neuer Ärger mit Gewehren

Das Beschussamt Ulm verweigert für zwei zivile Gewehre die Freigabe. Nun zieht der Waffenhersteller Heckler & Koch vor das Verwaltungsgericht.

www.faz.net

Heckler & Koch: Waffen-TÜV verweigert Zivilgewehren die Zulassung - WELT

Der Streit zwischen dem führenden deutschen Waffenhersteller Heckler & Koch und dem Beschussamt Ulm eskaliert. Die Prüfer verweigern für einige zivile Gewehre den Freigabestempel. Es geht um wenige Hundertstel Millimeter.

www.welt.de

Not sure if this is where the HK416 story is coming from and I've never measured a HK416 barrel (but do own a few of those BNP-proofed MR223s), but at least HK did and still does manufacture tapered barrels for the HK416/MR223 platform in general.

The MR223s are - the name is kind of foretelling - marketed and sold as "Match Rifles" and the tapered bore is said to increase precision. If that feature is really necessary for a HK416 military rifle, I'm not so sure.

 

Interesting. Seems to be yet another difference between US available 416 series guns and euro available 416 series guns.

In my experience, no 416 barrel in the US that i've had my hands on has had a taper beyond the first inch (25.4mm) or so, past the chamber in the throat. Zero taper near the muzzle. Although on an odd note, the bore seemed to loosen a little right at the gas port and then re-constrict.

After reading the lead contamination results, i'll stick with the barrels HK sells in the US.

Insofar as a taper increasing accuracy, the taper at the throat does so "in theory" as it allows the bullet a longer time to align correctly with the bore from the chamber/case mouth, hence providing more consistency as the bullet passes through the bore.

From what i understand, the concept of taper at the muzzle was used more for increasing velocity in large bore anti-aircraft guns before it was ever applied to small arms where its effectiveness is debatable at best.

An anecdotal note: when i purchased an MR556 back around the 2008/2009 time frame, it produced groups around an inch and a quarter in size (3cm-ish). After i had the barrel cut from 16" to 14.5", the groups dropped to under 1/2" (13mm-ish).

 

Interesting. Seems to be yet another difference between US available 416 series guns and euro available 416 series guns.

Beware, the MR223 is - by design, to get BAFA and BKA clearance that the gun is developed "for sporting and hunting purposes" and thus not a "weapon of war" - not a "416 series gun"!

Insofar as a taper increasing accuracy, the taper at the throat does so "in theory" as it allows the bullet a longer time to align correctly with the bore from the chamber/case mouth, hence providing more consistency as the bullet passes through the bore.

The taper actually does increase the MR223 accuracy (I don't know if the MR308 has a similar taper, but both the MR223 and MR308 were taken off the marked once the proofhouse denied the proofmark for the MR223, so I would assume so (although you shouldn't assume, I know...).

And this is IMHO also the reason HK is reluctant to change the hammer forging mandrel to a straight one, because their product would be worse for sporting purposes after doing so.
Thus they accept the current workaround shipping the guns to Birmingham.

From what i understand, the concept of taper at the muzzle was used more for increasing velocity in large bore anti-aircraft guns before it was ever applied to small arms where its effectiveness is debatable at best.

The conical barrel guns I am aware of were anti tank guns (Panzerabwehrkanonen, Pak) were designed to achieve higher muzzle velocities to get better armor penetration, while using special bullet designs to be able to do so. But THAT taper was much more aggressive than the one we're talking about. The some had a taper of 42 mm down to 29 mm, others had a taper from 75 mm down to 55 mm for example. That's 31% and 27% respectively.

The MR223 tapers from the 5.56 mm of the CIP definition down to the 5.53 mm you see stamped by Birmingham above. That's 0.5%.

So that's quite a difference.

An anecdotal note: when i purchased an MR556 back around the 2008/2009 time frame, it produced groups around an inch and a quarter in size (3cm-ish). After i had the barrel cut from 16" to 14.5", the groups dropped to under 1/2" (13mm-ish).

There are people cutting and turning down MR223 barrels in Germany, trying to get the MR223 lighter.
But these guys are few apart and they usually don't shoot any precision results, so I am not aware of any useful comparison of before and after as of now...

 

Bruh, the MR223 nd MR556 use the exact same operating system as the military grade HK416, with a %100 parts compatibility. Parse it, split hairs, obfuscate all you like, but they are all derived from the 416 operating system and thusly are of the 416 family or series of weapons.

Regarding the bore taper on euro guns, i'd like to see empirical data that proves an increase in accuracy. I don't believe one exists at this time.

Regarding the large guns, i did say the "concept"came from large caliber weapons, and the source i read several years ago specifically mentioned anti-aircraft guns. It does not surprise me that it was applied to other weapons systems. That being said, it seems the main article that comes uo in a quick search is wikipedia and it specifically mentions anti-tank guns. So please tell me you're not getting your information from wikipedia.

I specifically said "concept" because the 416 had to be designed around currently available ammunition and HK was forced to work within the bounds of available elasticity of these types of ammunition.

The fact that it doesn't exist on weapons sold to the US market is telling. I am left with the impression that the fact it remains in euro models is because it's merely a marketing point in an attempt to make it not seem like a "weapon of war" to the politicians. In other words, all sound and fury, signifying nothing.

There may be a slight full length taper to all 416 series barrels that remain due to the CHF process, but in my experience, it is so negligible as to be virtually unnoticeable, especially as the bore is of the correct internal diameter at the throat and a pin gauge passed through the barrel does not sieze at the muzzle (on US sold guns). The main taper at the throat that existed from 2004 ton2008 is completely gone.

I cannot find a single example of a modern sniper rifle/precision rifle that has a tapered bore at the muzzle, hence my skepticism at the accuracy claim. There have been a few references to standard issue rifles with tapered bores and all of those use cold hammer forging to manufacture the barrels, so i believe that the "taper" may just be a manufacturing artifact that someone decided they could sell as a "feature". Even though HK specifically removed tapering from their manufacture of military grade 416's after the lead contamination reports were released. These reports have already been discussed on this very website in the past.

Most references to tapered bores comes from 1800's weapons technology, the extreme tapering for use with proprietary ammunition in large caliber weapons, and artifacts remaining after the cold hammer forging process in modern guns, that really seems to be an afterthought, not a specific process identified as value added for precision specific weapons.

 

So please tell me you're not getting your information from wikipedia.

If you got that feeling, I'm really sorry.

I get some other feelings, so I'll leave your opinion to you. It seems to take up a lot of space.

 

Don't be so sensitive bro, we're just having a conversation here.

 

I'm not sensitive, I just prefer to not waste my time. Besides that it's 4:37 am here and the old man should go to bed.

So I'll just respond to a few points from above for now:

I cannot find a single example of a modern sniper rifle/precision rifle that has a tapered bore at the muzzle

Early MG1 barrels made by Rheinmetall had conical barrels for example. H&K and Steyr produced conical barrels for hunting rifles in the past, others did too.
That said, the hunting aspect should be in the past now, because with the lead-free spree in Europe this is going to create issues with solid bullets.

Regarding the large guns, i did say the "concept"came from large caliber weapons, and the source i read several years ago specifically mentioned anti-aircraft guns. It does not surprise me that it was applied to other weapons systems. That being said, it seems the main article that comes uo in a quick search is wikipedia and it specifically mentions anti-tank guns. So please tell me you're not getting your information from wikipedia.

The higher velocity achieved by the "squeeze bore" guns was originally designed for anti tank use to allow for higher muzzle velocities for better armor penetration performance while keeping the gun small and mobile enough so it could still be manhandled in combat.

While there might be some AA guns with tapered bores, AA guns quickly surpassed the manhandle-size and were used in fixed AA defensive positions around factories etc. and thus didn't have that focus on weight. And they shot a lot. Like really a lot. And those squeeze-bore guns have an durability issue due to the friction during squeezing that specially designed projectile. So there is a lot less to be gained from a squeeze-bore AA gun than a squeeze-bore AT gun.

The fact that it doesn't exist on weapons sold to the US market is telling.

Yes. But it may tell other things than you assume, mainly being production capabilities.

 

The HK416's in the US were all manufactured at HK in Germany.

That being said, we have the same chf capabilities here in the states at multiple manufacturing facilities.

The source i refered to regarding anti-aircraft guns specifically mentioned towed systems, not man portable.

Regarding the lead-free ammunition in europe, what are they now made from? There must be some ability to form the bullet to the lands and groovs, so i am curious as the the makeup of the available ammunition.

Lastly, are you aware of any supporting data for the accuracy claim regarding muzzle tapered bores?