Hexagonal Boron Nitride bullet coating

[NamibHunter]

Is anyone seeing a gain in their BC? I just started using hBN on 300gr Berger Hybrid OTM .338's. I am shooting in an ELR match on Saturday, and I have not had a chance to check dope and see what an actual BC gain is.

Not running a 338 (still dreaming...), so my data might not be applicable here.

Shot HBN coated bullet at the same speed as before with about 0.5 gn extra powder to compensate for loss of speed, i did NOT see a BC change, this was for a 6.5 CM. SD and ES did improve slightly.

When i pushed the speed up another 150-200 fps (via HBN coating plus a special powder), i did see a small BC improvement, i guess mostly from the higher speed. Can’t recall the exact nrs, but single digit percentage improvements. Something like 2 or 3 less clicks at 600 compared to Strelok prediction.

 

[NamibHunter]

Btw this video David Tubb posted on Youtube seems to indicate that their HBN is a compounded (blended) mix, and also contains their anti copper fouling agent to increase cleaning intervals. Did i interpret that correctly?

Also: The manual that comes with their kit says it is a blend of two different particle sizes.

For the folks who bought “HBN” off eBay or Amazon and who are not getting good results: Apparently some of the commercial stuff are NOT pure hexagonal HBN, and contains undesirable impurities, and i would recommend you try the Tubb formulation, it worked first time for me, no issues at all!

Also there are rumors that some batches of CUBIC Boron Nitride got mislabeled and shipped to consumers as Hexagonal Boron Nitride. The Cubic Boron Nitride is one of the best abrasives available, similar to diamond dust. Buyer beware!




It seems the Tubb HBN coated 115 DTACs are coated with the same blended formulation.

Not trying to promote one product over another, there are other bullet coating kits available that my shooting buddies are using, and they report that it works well. Can’t recall the name. Edit: Company is Bulletcoatings.com

 

[Daherc]

I shot my coated 300gr bullets at an ELR match yesterday. I was able to true my BC by shooting targets at 1400 and 1760 yards on Friday. I had to reduce the G7 BC from 0.429 to 0.410 to make my Kestrel match my dials. It was good at out 2203 yards, which was my farthest impact. I never trued my BC last season, so I cannot say the hBN lowered my BC.

I think the hBN is worth a shot if you are looking to get a little more out of your load.

I got mine from bulletcoatings.com, so I can’t speak to the purity of the hBN, but it seems to work.

 

[NamibHunter]

@Daherc,

Interesting! I would also be very surprised if an HBN coated bullet reduced BC. A bullet that wobbles a little when it leaves the muzzle can lead to lower BC. Can be a new muzzle brake that it not perfectly concentric, or mounted slightly skew (threads), a damaged crown, a carbon ring inside the brake (i had one!), and probably many other things too. Such a bullet typically stabilizes somewhere between 50-150 yards, and will often transition just fine into the subsonic zone, but drop is worse. Could also be bad mirage ‘moving’ the target you see to a false position... or crony error. Or a combo of “all of the above”!

I checked: My buddies are also using the product from Bullet Coatings, and they like it.

 

[NamibHunter]

I shot my coated 300gr bullets at an ELR match yesterday. I was able to true my BC by shooting targets at 1400 and 1760 yards on Friday. I had to reduce the G7 BC from 0.429 to 0.410 to make my Kestrel match my dials. It was good at out 2203 yards, which was my farthest impact. I never trued my BC last season, so I cannot say the hBN lowered my BC.

I think the hBN is worth a shot if you are looking to get a little more out of your load.

I got mine from bulletcoatings.com, so I can’t speak to the purity of the hBN, but it seems to work.

Are you loading to the same speed as before (same node), or are you pushing for max speed? Do you see the cold bore shot land in the group? Just curious.

 

[mudpig]

tag

 

[Daherc]

Are you loading to the same speed as before (same bode), or are you pushing for max speed? Do you see the cold bore shot land in the group? Just curious.

I did not get a chance to try cold bore grouping before my match. When doing a load ladder I was able to get 98 FPS faster with what appeared to be the same pressure based off bolt lift and signs on the case. My charge weight went from 93.0 grains of H1000 to 96.0 grains.

I am pushing for max speed for ELR. My previous load would have my bullets go transonic around 2100 yards, and there was a target we needed to hit at 2203 yards. I was never able to hit that with my previous load. I was able to connect with it this past Saturday, and I have a felling it was due to my bullet stating supersonic to that distance, and not dropping to subsonic right before that distance, but I am not sure.

 

[NamibHunter]

I did not get a chance to try cold bore grouping before my match. When doing a load ladder I was able to get 98 FPS faster with what appeared to be the same pressure based off bolt lift and signs on the case. My charge weight went from 93.0 grains of H1000 to 96.0 grains.

I am pushing for max speed for ELR. My previous load would have my bullets go transonic around 2100 yards, and there was a target we needed to hit at 2203 yards. I was never able to hit that with my previous load. I was able to connect with it this past Saturday, and I have a felling it was due to my bullet stating supersonic to that distance, and not dropping to subsonic right before that distance, but I am not sure.

You are having a lot of fun sir!

I am also getting ready to build an LR rifle. Not always sure where “Long Range” ends and where ELR begins! But hoping to hit targets out to 2,000 yards.

During my recent hunting trip to Namibia, i got invited by a group of local ELR competitors to go shoot in the mountains. One brought along a very nice 32” 300 Winmag with freebore cut for the 230 Berger and a suitable twist rate, and an aggressive brake. He had very little trouble out to 1,500 yards. He got a few misses in a tough switching 15 mph wind and then several hits on the 2.3 km target (that is 2,500 yards!). Very impressive! The second rifle was a heavily weighted down Sako TRG with a combo suppressor/brake in 338 LM shooting HBN coated 300 gn Bergers. Hitting 24”x24” steel targets was remarkably easy out to 1500 yards (consistent wind direction at the targets in the ravine), but it got very hard beyond that range. I managed a hit at 1,997 yards after multiple misses. When you shoot from one mountain top to the next the wind is very unpredictable. But what a rush!

HBN helped that 338 get to a pretty remarkable speed. It certainly seems to contribute enough speed to justify the (fairly minimal) effort involved on the reloading side.

Even for a 1000 yard rifle, it seems HBN often allows you to find a better node at a higher speed range that you could not exploit before without running into brass destroying pressure problems.

Talking to these guys i got the impression that many ballistic calculators don’t do a good job predicting drop in the transition zone and beyond into the subsonic region. Some of them use custom drag curves in Applied Ballistics and that seems to work well enough. I guess there are also other good ballistics solutions.

 

[Mitchell3006]

Does anyone have sources for the correct sized HBN (both bullets and bore) as well as the media? The ceramic seems like a good idea and I've seen jeweler's SS various shapes recommended.

I'd like to give it a try. I'm not sure if case capacity will work in the 6.5CM 130gr bullet RL26 loads currently using as it's compressed now.

I have used Lower Friction .com :[email protected] They are an industrial seller of HBN. They have it from over 5 to .5 microns. You need only decide what is best for you. Most folks use .5 for bullets whether they know it or not. I even do my cast bullets instead of powder coating. YMMV I use gloves and respirator. Not N95 mask. Particles too small for real safety with loose fitting masks. .5 microns it is said is also small enough it can absorb through the skin. It can also coat your lungs if your breath it in. I can not work outside so I have a fan to draw air outside to take away any dust. There have been industrial accidents that turned out badly for anyone who inhaled a dust cloud. Now your would have to spill or drop your 4oz container on the floor and try to sweep it up to cause that kind of dust. But, sadly it does happen so I would rather talk about best practices and let folks choose.

Keep HBN dry. I'll say it again. Keep HBN dry. So what ever time of the year is driest for you do a huge load of bullets and clean AND treat all guns that you want treated. I now have humidity gauge(s) in my shop. My guess is that 90% of everyone's issues are humidity or unclean bullets. I only have one great shooting rifle. But the AR's and hand guns clean up much easier after treating the barrels. Don't do the chambers without researching possible ill effects. 20 minutes vs an hour or more time saved cleaning... That alone was worth it for me. You will get a US Pound for the cost of 4oz at LowerFriction.com. Worth it when you deep clean and do all your guns at once. I gave kit's away for my PRC friends to use on their guns and bullets. Get small ml spoons on Amazon. Again a dozen plastic for the cost of one regular metal spoon. There are enough video's to give you a lot of idea's. Tubb's started the HBN protocol for application. But I have used all of the one's shown on YouTube and all worked for me. Moisture is your biggest variable. Keep it dry! Small Groups & Good Luck