HBN

We been hearing about this stuff for like 10 years or so. Its supposed to be the "better" version of what Moly was. The concept is basically this. If you make the bullet more "slick" with less friction, thus you can jack up the powder charge and not get huge pressure (More than without HBN). For example. With Moly, you typically hear you can do ~.5 grains more in 223/556.

We had issues with HBN, and are the first ones to tell you, we are not experts at this. But, we did so much research, read everything, watched everything, talked to people in person, did multiple attempts and after all that, finally managed to load some bullets that made sense.

Despite all this, even if it was good result, we don't like it because its super messy and I don't think you want to breath this in. Its so fine, it will make a cloud worse than "flour" does, so you have be careful, and I would wear a respirator to handle it.

Here are some pics of the process

Step 1. Clean the bullets and dry them

We washed all bullets with soap, cleaned then very well, and dried them. Ball bearings too.

Step 2. Place small amount, (less than 1/4 teaspoon) in container

You don't need much.

Step 3. Ball bearings, bullets and HBM in that container. Tumble it.

We tumbled it 2 hours

Step 4. Clean off excess

It comes out of tumbler like this. And its very hard to handle, slippery.

Step 5. Ready to load

We used terry cloth to wipe them down, but still you can see its in the pores well.

Step 5. Load it

HBN bullets on right, non on left.

We used Sierra MK

New bullets used

100 yards

First off, this is NOT a test for accuracy, its a test to see if we can learn a few things about HBN. Just to see its impact. Here is how we setup the gun that shot the HBN.

Step 1) Clean barrel very well.

Step 2) put some HBN in alcohol, and dip patches in that milky mix, and then run it through barrel a few times to coat barrel in HBN.

Another gun very similar, same length barrel, very similar FPS as HBN barrel was used, so there is zero cross HBN contamination.

Data is below.

On purpose, we loaded way over manufacturers maximum SAAMI load data, using Starline 5.56 brass and CCI41 primers. These are 20" barrels, using 77 grain SMK at 2.255, using Accurate 2520 and VV N135.

Of note, the HBN causes some effect on seating the bullet. Learning about this, we had brass neck at .222 and the bullets are obviously .224. So 2k neck tension. That usually seats at like 45-60PSI on the arbor press. But when you run 2k neck tension on 5.56 brass with this HBN? Seating pressure was over, easily, 120 PSI, and it dented the ogives. So we discarded those. We then tried different brass brands, tried coating the neck in HBN, tried many things, nothing had significant impact. So then, we changed the expander ball to .224, which in reality makes the brass .2235 or so, so you have 1/2 of 1 thousands neck tension. With HBN, this loaded to about 60 PSI of seating pressure, while with the One shot it was around 20-30 PSI of seating pressure. Also the spread of seating pressure was much larger with HBN, as the One shot and the normal, was consistent seating pressure within 10 PSI. HBN was like within 30 PSI.

We did One Shot, because we BELIEVE that Hornady ONE SHOT is better than MOLY, or anything you can buy, for ease of use and its impact on shooting. We proved this in several tests now. The ONE SHOT is basically probably about ~.4 grains SLOWER velocity, than Normal.

What is conclusion?

Conclusion is....some evidence? First of all, look at the brass pics...and brass measurements. You read right, that is/was 2925+ average out of a 20" barrel using 77 SMK. That is smoking hot. It felt powerful for sure. But zero real issues, other than some brass has some marks, but primers are not bad. CCI41 are hard, so thats not saying much...

We don't know, but we think the HBN coated bullets had erratic SD and ES because neck tension was high. Simple as that. We believe using Hornady ONE SHOT to soak the bullets before loading them, is vastly, vastly superior to anything else we tried, and is super clean and so easy. Look at result. N135, 23.5 is only average 13 FPS more than the 23 grains of Normal. So basically, One shot SLOWED the velocity down, around .4 grains. Sounds like Moly right? Its only 3 shots, but this is just learning things...but look at the pattern? ONE SHOT groups are better SD and better ES than other 2, and LOWEST velocity.

ONE SHOT coated bullets were also the lowest seating pressure....

So in the end, we didn't see HBN doing what some say it is supposed to do, but this is small learning test and not the end all, of course. We just sharing our experience.