Lube Barnes Triple-Shock bullets?

[SL11]

I am guessing that other cast bullet shooters have looked at the "bands" on the all-copper Barnes Triple-Shock rifle bullets and thought "those really look like lube grooves." I know that Barnes earlier had tried some dry surface lubricant (non-moly) on their X-bullets (the XLCs) before going to the recessed rings in the driving surface to reduce friction in the bore. Both techniques seemed to be somewhat effective in reducing bore friction and copper fouling.

I know that the first bullet down my cleaned and still slightly oiled rifle barrel comes out faster than the later bullets in a string. The cleanliness and lubrication seem to be a good thing, but not maintainable unless I want to clean the bore before each shot. So, typically, I shoot a couple of "fouling shots" and then get serious about measuring velocities and accuracy with the bore condition that are an equilibrium condition for the ammo.

So, I am wondering what would happen if the back one or two grooves in the bare-copper Triple-Shocks were packed with a good high-pressure lubricant like LBT Soft. Would that decrease pressure even more and allow still higher velocities? Could I swab the bore with a light coat of the lubricant before the first shot and then reach some sort of lubricated equilibrium that would give me consistent results after a few shots?

Before I buy some Triple-Shocks and start yet another reloading experiment, I thought I should ask whether anybody else has done this already. If so, what did you learn? Any other thoughts from anybody?

SL1

[runfiverun]

it has been tried
those bands are there to lower pressure
lube is a liquid even a solid one and doesn't compress.
you will have to keep your velocities low to keep your pressures down
so zero gain and actually a loss on this one

[SL11]

Runfiverun,

You didn't give me much in the way of details, there. Did you do this yourself or read about it. If you read about it, can you give me a reference?

SL11

[runfiverun]

i did read about it but cannot re-call where
i also tried it by shooting new brass and miking case head area
compared to factory ammo and run across my chrono
i lubed these with hard lube in my star lubrisizer. i only bought 50 of these
i was leery of doing this
as i know guys that swage their bullits lube them first to keep the lube grooves
in the bullit when swaged.
and found that all iwas doing was filling up the grooves that were cut in there
to lower the pressure.
if i was to try this again i would likely look to lube the bbl or bullit with
[moly] which i dont care for or some other thing.

[SL11]

If I try it, I will use soft lube, put it in only one groove, and may not fill the groove full. My idea is simply to spread a little lube back on the bore as the bullet passes and scrapes out some that is already there.

Lead bullets actually put the lube under pressure as they compress and try to close-up the grooves when fired. Copper bullets really don't do that. The lube will have to be liquid enough to flow due to the forces from accelerating it.

The grooves in the Triple Shock bullets serve two purpose:
1. They decrease the bearing surface to decrease frictional forces on the bullet, and
2. they provide a place for copper displaced by the lands to go, which
a. lowers the force needed for engraving the bullet, and
b. prevents the formation of little "tail fins" at the base of the bullet which can really mess-up the accuracy.

It's not clear to me why your hard lube would increase pressure a significant amount. It does present a bearing surface, but that surface should be too slick to make much friction. More likely, it is increasing the engraving force by resisting displacement of the copper into the [bullet]grooves. But, the copper bearing surface of these bullets rarely touches the bottom of the grooves in the bore, so it would seem like there is a good place for the excess lube to go if it isn't too hard.

Anyway, thanks for the heads-up on pressure increase. I have been considering whether to use my bolt gun or my Contender for the experiment. The bolt gun really doesn't need any more umph, while the Contender could benefit. But, the bolt gun is the safer choice for the experiment and also allows me to use case head expansion as a pressure check. The Contender is not strong enough that I want to expand case heads in it, and the pressure ring method is hard to make very reliable for distinguishing pressure differences.

The first test would be to see if I could make the lube bullets shoot consistently. If not, there is not reaon to go further.

It would be nice if Barnes would simply put their XLC coating on some of the Tripple Shocks for us curious types.

SL1

[runfiverun]

i would really like to hear the results of anything that you find
i think what you said about the lube is pretty close to what was going on
but the one or two bullits i recovered looked a lot like my cast bullits
do when i get a whole one of them back.
where there was a lot of metal set back and the grooves were still
pretty full and square
may have been a fairly tight bore?

[21buck]

As I see it there are limited choices. The barrel or the bullet. I found some dry film lubricant for the barrel and action that you might be interested in. The website is Accuvel.com . It says that the coating is 100nanometers thick! I wouldn't be afraid of excess pressure. In fact after reading the entire website, the stuff enhances the performance of your rifle in accuracy and velocity.
Just my .05cents

[SL11]

21buck,

Thanks for the link. I had never heard of the stuff, before. Their "Order" page says "under construction" so I don't know how much it costs.

I think I will wait for some others to test this stuff before I start putting it in my bores. I have fewer barrels than there are non-removable and hard-to-remove coatings for them, so I try not to be the first in my group to buy such stuff.

Other options include a company that will coat bullets and other things with boron nitride. See DavidTubb.com.html and Momentive Performance Materials . But, they have to do that in a factory and it costs $$.

SL1