HBN coating

[Cuando]

Ca

 

[Cuando]

Hard to grab a good image as I was losing the light.

 

[GrocMax]

I run nothing but bullets and hbn in a dedicated vibratory tumbler bowl for about ten minutes. Loud and obnoxious, but it works really good and is quick. I use a tiny Lee dipper to measure. It only takes a little to coat a lot.

This method works well for me with enough bullets (500-1500 depending on size). Heat lamp in the winter speeds things up.

 

[Coolhand]

Interesting observation recently when I decided to HBN some 55 Grain Sierra Blitzkings. I tumbled the projectiles in Lyman Media as per usual , then tumbled the bullets in BB's and HBN for the usual hour or so, the HBN would not stick to the 55 grain bullets.
The odd thing is that my routine will coat 155 grain Sierra 2155 & 2156 with no issue. Is it likely that the copper jacketing of .22 cal bullets is somehow different to 155 .30 cal ?
The only change I have made was to replace the plastic screw top container with a tumbling drum used for polishing gemstones.
The drum is made from a hard rubber material and has an inner seal and a tin plate cover over the seal which screws down tight.
At a guess I would suggest that the rubber of the drum is actually rubbing off the HBN as the drum rotates and the BB's are not getting the chance to impact the HBN onto the bullets.
I cleaned everything off and put the 55 Sierras into the old plastic container and run them for 2 hours. The result was less than satisfying.
The 55's looked spotty with small clumps of HBN all over not smooth like the 155's when the excess HBN is dusted off.
I have been using a 22 LR case to measure the HBN which is approx 9 grains of HBN for 100 155 projectiles.
I am going to try it all again to refine the process with the 55 grain Sierras.

Mike.

 

[r1200mike]

So, how many shots does your coating last for? Are you doing this with uncoated bullets?

Boyd, Uncoated bullets. I really don't shoot much over 120 rds. before cleaning the barrel. I just reapply after every cleaning. No copper fouling.

 

[JimPag]

After reading that article from the USAF on coating of bullets, HBN vs Moly vs Danzac, it is nothing more than a big waste of time.

 

[zipollini]

After reading that article from the USAF on coating of bullets, HBN vs Moly vs Danzac, it is nothing more than a big waste of time.

When seating my Hbn coated DTAC 115s I never have to use any lube on either my case necks or bullet. They glide into the neck with very little and very even pressure.

 

[JimPag]

When seating my Hbn coated DTAC 115s I never have to use any lube on either my case necks or bullet. They glide into the neck with very little and very even pressure.

Why would you use lube in the first place to seat bullets?

 

[zipollini]

Why would you use lube in the first place to seat bullets?

Why do people use graphite or mica to seat bullets ? Same reason.

 

[jsthntn247]

Everything I've read says they need heat and a rotary tumbler works best with bb's. I got to thinking, why not wrap the bottle in a thick sleeping bag and throw them in the dryer with a load of cloths. Worked like a charm, they are coated now. Don't think I'll be doing that with my match bullets but I at least got some to stick.

 

[JimPag]

Why do people use graphite or mica to seat bullets ? Same reason.

Never heard or seen anybody ever doing that. Does anybody else out there do the same thing?

 

[wedgy]

In a thread on LRO there seems to be an issue with ammo that has sat a while ~6 months having the bullets bind or stick to the case causing different velocity. I saw this in some ammo I had loaded, by trying to push the bullet a little lower it would make a snapping noise when the bullets broke free of the case, instead of just having an even resistance. If the bullets are for hunting make sure the tips are open because the HBN can fill and clog the tip which could lead to a nonexpanding bullets.
http://www.longrangeonly.com/forum/showthread.php?1796-hBN-bore-treatment

 

[jsthntn247]

In a thread on LRO there seems to be an issue with ammo that has sat a while ~6 months having the bullets bind or stick to the case causing different velocity. I saw this in some ammo I had loaded, by trying to push the bullet a little lower it would make a snapping noise when the bullets broke free of the case, instead of just having an even resistance. If the bullets are for hunting make sure the tips are open because the HBN can fill and clog the tip which could lead to a nonexpanding bullets.
http://www.longrangeonly.com/forum/showthread.php?1796-hBN-bore-treatment

Thats a common avoidable problem that's not caused by HBN.

 

[wedgy]

Maybe I wasn't clear, they are using HBN to avoid the bond between the case & bullet, and help achieve more consistent cold bore shots.
On a side note the velocities with coated bullets are lower with the same charge weight.

 

[rardoin]

Never heard or seen anybody ever doing that. Does anybody else out there do the same thing?

Yes, I have and still do. I either dip the case mouth in 'motor mica' prior to charging, then seat a bullet or...when I forgot and charged the case....dipped the bullet base in mica and seated. In new cases I definitely found that the bullets seated easier and more smoothly. In fired cases that still have carbon in the necks the difference was not greatly different.