I went to a new rifle range today, a farmer and his brother created it on the family farm and it is actually quite nice, as inexpensive rifle ranges go.
http://www.harrisoncreekgunclub.com/I spent 5 hours there, wringing out hexagonal boron nitride coated 160 grain bullets and R19 powder. Upshot is that this powder along with the bore & bullet coating allow you to tag 300 fps on top of what you used to be able to get out of a small .308 based case and an elk-sized heavy weight 7mm jacketed slug.
MM, the 30-06 load that got your eyebrow was a 165 grain bullet going 2,750 fps. You thought it was a kicker in that HEAVY BARREL heavy gun with the bi-pod rubber feet that soak up a lot of the recoil motion. That gun is not a carry weight gun at all, it is a stationary hill top gun.
Instead, I was shooting the light 7mm-08 carry rifle, tossing 160 grain bullets at 2,975 to 3,150 feet per second out of a 22 inch sporter weight tube. And yes, it kicked hard, to the point that after 5 hours of doing it sporadically (barrel was heating up something fierce at each shot and needed 15 minutes between shots to cool down) I had had enough, and yes, my shoulder is a bit sore tonight.
And yes, I know, you can't do that.
Im-fricking-possible. 2,850 fps is the highest fps listed for 160 grain bullets, even in the old unregenerate Speer #11 reloading manual.
Trick is pre-treating the barrel with nano-fine hexagonal boron nitride then shooting bullets that are impact coated with the same stuff. Once the barrel engraves the bullet it just zips on down the bore with practically no barrel drag. Energy once spent overcoming friction becomes SPEED and the peak pressure is actually less as the bullet gets on down the bore ahead of building up the old magnum pressures like max loads used to do.
Book max loadings show no signs of pressure and give 300 extra feet per second of velocity.
Now the real evil grin stuff --
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so now you can use more powder now and get even more velocity and eventually wind up getting up to the same level of primer sign that you used to get at book max -- but at recoil levels that make old men decide to quit early before they hurt themselves.
Accuracy was surprisingly good, with the increases in recoil causing the groups to march on up the target but they all hung in around 2 inches in size for each charge level.
And, as in any ladder series, the sweet spot showed up with a couple of increases hitting the same point of aim. My sweet spot is 49-50 grains at high 2900s to low 3000s in fps. Above this pressure and velocity both get more erratic and the butt pad begins banging up the operator too too too much.
So, it was a good day at the range. I learned something new, and proved to myself it actually works.
BTW, no copper fouling was seen at all during cleaning. And clean up only required getting the carbon out of the grooves, fairly easily done with normal bore products using the clean, soak, clean routine drill.
This is what people love about hexagonal boron nitride , it isn't corrosive, it does not attract atmospheric moisture and you can leave a pre-treated bore in your gun for several days with no oil film and your first cold bore shot will group with all the rest of them as you don't ever have a film of oil in the bore to deal with.
Next, since you get no copper fouling, you can choose to leave your bore alone for the entire hunting season if you wanted to that and just clean it when hunting season is over -- all shots fired will land in the same group that way.
MM, finally my loctite'd scope tube stayed put in the rings and didn't walk anywhere.
Finally. I shot the rubber flip cover off the front of the scope a couple of times, but it just presses right back on again and I could fix it in place with loctite too, I guess. I won't bother since nobody is going to be shooting these sorts of loads for the chuckles of it.