HBN on new barrel, or break in barrel first?

[odoylerules]

I have a new barrel coming for my desert tech in 300 Norma. I want to run HBN coated bullets. Like the title says should I do that right off the bat or work up a standard load with a naked bullet first then work up an HBN load? Thanks in advance

 

[ar10ar15man]

nek'id bullets will not compare to coated.
so that data is not useful
i record all shots, do the same

 

[odoylerules]

nek'id bullets will not compare to coated.
so that data is not useful
i record all shots, do the same

Yeah I know it'll be very different, I was wondering if there's any benefit to working up a standard load first because of the break in of the barrel

 

[MagMan]

I would treat the barrel with HxBN/alcohol wash and start with treated bullets.

 

[tbrice23]

Yeah I know it'll be very different, I was wondering if there's any benefit to working up a standard load first because of the break in of the barrel

I like to do a proper barrel break-in session on the barrel first. Then I'll shoot a couple of range sessions afterwards, about 50 to 60 rounds total with naked bullets before I start HBN load development. I believe the barrel will then be "settled in".
However, I don't believe it will harm your new barrel, but it might not break-in/settle down as fast.

 

[BallisticsGuy]

Start with coated if you're going to use coated. Otherwise, what's the point of coating. My barrels have all settled down within 10 rounds starting wtih HBN coated.

 

[MLN1963]

I have a new barrel coming for my desert tech in 300 Norma. I want to run HBN coated bullets. Like the title says should I do that right off the bat or work up a standard load with a naked bullet first then work up an HBN load? Thanks in advance

I would clean the barrel thoroughly, ending with rubbing alcohol and leave it dry. Load up your coated bullets for testing. I might load 10-15 extras and fire them first to break in the barrel so to speak.

IMO all you are doing during barrel break in is smoothing out the machining marks in the leade left from the reamer. Once those have been knocked down you aren't really changing anything significantly. You may lay a little copper down in a rough area but you will likely be doing the same with the coated bullets.

 

[codyadams]

The last two builds I have done with HBN I did not do my normal barrel break in period, just started load development with HBN coated bullets. I noticed zero difference from doing your standard barrel break in procedure and then starting load developement, other than I saved some components. Load work up was consistent and I did not notice any major change. They slowly got faster for the first 40-60 rounds or so, but only a total of around 25 fps. It likely has no scientific merit, but it makes me feel warm and fuzzy knowing that every bullet fired has had HBN, so the bare, virgin bore was impregnated well with the stuff.

The rifles were a .264 win mag in a Krieger barrel and a .338 Norma in a Carbon Six barrel. The .264 wm has right around 100 rounds through it, and still no copper fouling is visible. The .338 Norma has around 80 rounds with the same result. Both shoot ridiculously well.