New 6mm CR barrel

[rampant]

Building a custom 6mm Creedmoor rig and am struggling to find an AU barrel maker who can make a 26" 416R in 5R single point cut.

And if that isn't tricky enough, nobody seems to have jumped on QPQ nitriding barrels? Does anyone know of gunsmiths providing that service? I figured with the drop in barrel life with the faster long range calibers there'd be serious take-up in nitride treating to extend barrel life.

Are we just too small a market?

[Bill]

Mate looked into it a couple of years back as he wanted to get his barrel done, the mob done south only do the Barrels they sell. Not aware of anyone else offeringthe service, I ll see if I can find the details

[rampant]

Thanks Bill appreciate it. I don't mind buying a barrel from the same place if they can meet spec. Here's hoping! Otherwise I found these guys who do it for industrial equipment: http://www.acemts.com.au/heat-treatment/tufftriding/ I'll make enquiries next week.

[Bill]

GC Precision Developments is the mob that do the Nitriding.

https://www.facebook.com/gcpd.arms.australia/

[rampant]

Ahh ok thanks I've reached out to see what they can do! If you don't mind me asking, what twist rate did you go with on your 6mm ARC?

[Bill]

1:8 Bartlein 5R, more interested in it shooting 90gr for hunting and Ill play with 103-108gr for range work. Thou I'm have a heap of fun with 55gr NBT and Berger 64gr Column's.

[SCJ429]

Is there any evidence that it makes a difference. Have you thought of cryogenically heat treating your barrel?

[rampant]

There seems to be quite a body of evidence available showing the QPQ method increases surface hardness, reduces surface friction and assists in significantly reducing oxidation. Anecdotally lots of military barrels are nitrided but that may just be to protect the barrel from grunts who don't clean them properly (speaking from experience

I did find a research paper that showed a comparison of surface hardness between nitriding and cryo treating (noting the nitriding process used was gas which I've read is not as good as liquid salt bath nitriding). In the comparison nitriding created a higher surface hardness compared to cryo heat treatment, but the kicker was combining both methods resulted in the highest surface hardness of all treatments and to a greater depth in the steel.

It'd be awesome if someone productised this, IMO with the higher pressures and faster velocities from the newer cartridges reducing barrel life to 2-3000 rounds to me it just makes sense to prolong your barrel life by hardening it up with no apparent loss of accuracy. Considering there's possibly only 1 gunsmith nitriding barrels in Australia I don't hold much hope though. Cryo would add considerably more expense to the process.

Research paper: https://citeseerx.ist.psu.edu/viewdoc/d ... 1&type=pdf
Nitride standard: https://www.sae.org/standards/content/ams2753d/
NRA review on QPQ: https://www.shootingillustrated.com/con ... -finishes/

[SCJ429]

Thanks for that. It is usually only the throat that erodes away from hot gases and I would be surprised if nitriding would survive for long in this area. My thoughts are that I am better off buying a new barrel at $660 and start again. The fact that there is no demand for this by the guys competing tells me that someone tried it and it made no difference. Save nitriding for your crankshaft.