HBN coated bullets

[rifleman700]

I have used pre-coated moly bullets, Danzac coated by me and various other coatings and I have found hBN to be the best. I only use them on 17 caliber high velocity cartridges where round counts can get high and limits the cleaning substantially. If load was developed bare then powder will need to be added to get velocity up to original speed.

I get my hBN here - see link below. I clean then heat bullets and then vibrate tumble them in pill bottles with various sizes of stainless media. No issues.

http://www.lowerfriction.com/product-page.php?categoryID=2&gclid=CKXtqezA67wCFYFhMgodMDUAkw

 

[fgregorio]

Properly plated, (without heat) grasping a bullet plated with hBN is like picking up a watermelon seed from a wet floor It begins and ends in your mind.

Yep Its all about surface ductility. Metal becomes more surface reactant at higher temperatures. Same as if you heat a barbeque grill and oil it vs a cold barbeque grill and oil it. At a more scientific level, copper's surface granular structure (size of the surface grains) increases in size as you increase its temperature. This allows the HBN particles at that time to lodge themselves in the crevices of the copper surface grains deeper and easier.
Similar:
https://books.google.com.au/books?i...epage&q=impact coating vs temperature&f=false

Hope this helps, more let me know.

 

[BenP]

I'm a newbie to the hbn coating deal. Im wondering if you can help accelerate my learning curve.

I built two load ladders for a straight .223. I loaded a few min loads and a few extra max loads according to Hodgdon website. Loaded the mins and book max's to compare to published velocities. The ladder was in .2gr increments.

I shot through the two ladders low to high. I loaded from just under max up to 105% of book max. I was attempting to find a functional max load for my rifle + the coated bullet combo. As i shot through the ladder the second time my velocities were all over the map compared to my first time through. Differences from 13 fps to a full 100fps on the same load.

I precoated the barrel with the alcohol slurry. Ive got a 26" stainless varmint barrel. I also shot 5 coated fowlers before i started the ladder.

25.8gr is max i shot up to 27gr of cfe223. The primers were starting to show a splash around the firing pin mark but still not flat and no hard bolt lift at 27 gr.

I recorded each velocity and can show you the chart if you care to see. The second string was all faster than the first string except one. Some of them A LOT faster. Care to try and help me sort this out guys?

 

[T-shooter]

Curious to see what experience people have had with HBN coating bullets. What are some of the benefits and drawbacks? What kind of application were you using it in?

I tried it every possible way I could think of. Here is the post:
http://forum.accurateshooter.com/threads/hbn-not-for-me.3931997/

 

[WyleWD]

I'm a newbie to the hbn coating deal. Im wondering if you can help accelerate my learning curve.

I built two load ladders for a straight .223. I loaded a few min loads and a few extra max loads according to Hodgdon website. Loaded the mins and book max's to compare to published velocities. The ladder was in .2gr increments.

I shot through the two ladders low to high. I loaded from just under max up to 105% of book max. I was attempting to find a functional max load for my rifle + the coated bullet combo. As i shot through the ladder the second time my velocities were all over the map compared to my first time through. Differences from 13 fps to a full 100fps on the same load.

I precoated the barrel with the alcohol slurry. Ive got a 26" stainless varmint barrel. I also shot 5 coated fowlers before i started the ladder.

25.8gr is max i shot up to 27gr of cfe223. The primers were starting to show a splash around the firing pin mark but still not flat and no hard bolt lift at 27 gr.

I recorded each velocity and can show you the chart if you care to see. The second string was all faster than the first string except one. Some of them A LOT faster. Care to try and help me sort this out guys?

You didn't mention how you coated them which seems to make a difference from some of the posts I read on this old string. Seems that everyone has either their own way of coating them, 1) their way and 2) following the directions provided with the kit. I know of at least half a dozen competitive shooters that use HBN coated bullets with no issues and they are definitely accurate. I was skeptical of them at first, but in the end they shoot great, didn't have to change my load(s), first shot accuracy, much less cleaning too. We use this http://www.davidtubb.com/bn-boron-coating and just simply follow the directions provided. There are also some videos on YouTube if you're a visual learner. Just our experience with them. WD

 

[BenP]

I started with an alcohol bath and them tumbled them with a few ball bearings in a pill bottle. It is a little full and im using a rotisserie motor to turn the bottle end for end (3 rpm) let them run all night.

First picture is after the slow tumble.

Second picture is after i dropped the bottle in the vibratory tumbler. I left the bottle in there for a few hours.
They did seem slick but it seemed to wipe off. Nearly completly. Im considering the dryer method. As described by others on here.