Non lead ammo barrel - what is that?

[mark-hunter]

So, gents,

First rifle marketed for non lead ammunition was one of Steyr rifles few years ago.

Next what caught my attention was Haenel Jaeger NXT (straight pull) also marketed with barrel for non lead ammunition.

So, what is a rifle barrel for non lead ammunition? How is it optimized for non lead ammo?

Any idea?

Here is what factories are saying:

Haenel: And the barrel is a genuine Green Barrel has been specially optimised for the use of lead-free ammunition.

Steyr: The LEAD FREE edition is the first one from STEYR ARMS especially designed rifle for the use of unleaded ammunition.

Maybe some more....
Here are the links.

Jaeger NXT – C.G. Haenel

The JAEGER NXT straight pull bolt action rifle offers much more of everything: more speed when cocking and repeating, more robustness in daily use, more safety and more good feeling when hunting.

www.cg-haenel.de

LEAD FREE | STEYR ARMS

STEYR ARMS does not only look back to 150 years of tradition but also takes the challenges of tomorrow.

www.steyr-arms.com

 

[Grumpy gumpy]

Intriguing, I wonder if the rifling is shaped differently, bit like Metford and Henry sort of different
gumpy

 

[Excessexpress]

Faster twist perhaps, otherwise Grumpy might be on the mark. Of course it might also be….marketing bollocks!

 

[mark-hunter]

Faster twist perhaps, otherwise Grumpy might be on the mark. Of course it might also be….marketing bollocks!

As per technical specs, rifling twist is quite common and nothing unusual.
This is for Haenel NXT:
.30-06 Spring. (11,0") / .308 Win. (12,0") / .300 Win. Mag. (11,0")

 

[Jäger_Ivo]

Steyr - The barrel profile with six lands and grooves (standard is 4) is optimized for solids. The less flexible solids proceed much more evenly into the barrel due to the smaller diameter of the fields.
I think after reading the original German text it means shallow rifling.

"Das neue Feld-Zug-Profil mit 6 Feldern und Zügen ist optimiert für Solid Geschosse. Das wenig elastische Solid Geschoss presst sich auf Grund des kleineren Querschnitts des Feldes erheblich besser ein."

 

[Hunter-Habib]

Just like many modern shotgun barrels are designated as "safe for steel shot", many modern rifle barrels are made to a higher vickers (unit of metal hardness) so that they don't get damaged overtime with prolonged usage of monometal bullets (which have less give in them than conventional lead cored bullets). For instance, Heym employs Cut Rifling which is stronger than the rifling found on many vintage rifles (or even those currently manufactured by most of the heritage English gun houses).

And yes, I have seen (both firsthand as well as photographs of) many vintage rifles get their barrels damaged (or at the very least, have their rifling worn through) after prolonged usage with monometal bullets (esp. those made of naval bronze or without bands on them to relieve strain).

 

[Excessexpress]

Banded bore riders have been the better choice ever since the Barnes X produced pressure spikes. Some projectile manufacturers get it, some don’t.

 

[mark-hunter]

Just like many modern shotgun barrels are designated as "safe for steel shot", many modern rifle barrels are made to a higher vickers (unit of metal hardness) so that they don't get damaged overtime with prolonged usage of monometal bullets (which have less give in them than conventional lead cored bullets). For instance, Heym employs Cut Rifling which is stronger than the rifling found on many vintage rifles (or even those currently manufactured by most of the heritage English gun houses).

And yes, I have seen (both firsthand as well as photographs of) many vintage rifles get their barrels damaged (or at the very least, have their rifling worn through) after prolonged usage with monometal bullets (esp. those made of naval bronze or without bands on them to relieve strain)

I think that modern industry came to relatively small list of acceptable materials for barrels, which are of higher quality then pre ww1 barrels.

This is now standard for all barrels (lead and non lead optimized)
Chrome moly and stainless steel.
Chrome moly are made of, in EU standard EN 19, or EN 24, American standard 4140, 4150, 4340.
Stainless steel will be 416.
Hardness of material will be between 25 to 32 HRC.

On bullets - older barrels were subject to wear and tear due to use of monolithic bullets, but modern monolithic bullets are made with external radial rings, that reduce the friction and wear of barrels which are within above standards. So, this part of problem has been dealt with and tackled.

So, in conclusion and in my perspective, having deducted all variables above, and under presumption that industry did not change steel quality standard for few non lead rifles - because barrel making process is still the same and requires same tools (cut rifling, button rifling and forging):
I think the non lead optimized barrels should have been optimized by profile of the rifling, but which rifling profile and how is it made, I have no idea.

 

[Kalthoff]

Non-lead bullets are lighter than lead bullets.

Therefore the optimal rifling twist rate is different for non-lead and lead bullets.

It will be interesting to learn if those two manufacturers mentioned in the first post, have discovered something else that can improve performance. Their websites give no specifics.

 

[colorado]

"We deal in lead friend"

All I have to say

 

[Wyatt Smith]

I wonder if it’s the type of rifling as well, was it Glock pistols that polygonal rifling and therefore could not use lead bullets.(non jacketed)
I also suspect it doesn’t mean lead free, just not plain lead. (Non jacketed)
Just speculation however.