Barnes 30 cal 212 LRX

Looks like the new 208 LRX may be a better balance overall for 300WM and down but then again maybe not.
I would have to get a faster twist with either one.
 
This will be a great offering. 212gr 30 cal LRX Bore Rider with a .705 BC.
Hi! I'm just getting into reloading and hunting here. I'm looking at the 212 Bore Rider vs. the 208 for a MPA 300PRC I have on order. The 212 only has one band cut into it. In some places I've read that these bands are to allow for flex to reduce wear on the barrel. Can anyone speak to if that means the 212 will cause more wear than the 208? I don't want to burn my barrel, but with the weight and higher BC the deflection in a crosswind is some 20% less than the 208 so at least on paper it looks amazing...
 
Can anyone speak to if that means the 212 will cause more wear than the 208?
No flex at all, what the grooves in the bullet sidewall do is remove bearing surface(the sides of the bullet that contact the rifling) and that lesser amount of contact/friction decreases the pressure because the bullet is easier to push out of the barrel. The bands can allow a heavier bullet to be shot faster than a lighter bullet that does not have the reliefs cut giving it more contact/friction with the barrel.
Notice the contact points from the rifling on this bullet and see how they only contact the high spots.... the groove reduce contact with the barrel = lower pressure which is longer barrel life. Or you can have equal barrel life but be able to shoot the bullets faster.
bl.jpg
 
Hi! I'm just getting into reloading and hunting here. I'm looking at the 212 Bore Rider vs. the 208 for a MPA 300PRC I have on order. The 212 only has one band cut into it. In some places I've read that these bands are to allow for flex to reduce wear on the barrel. Can anyone speak to if that means the 212 will cause more wear than the 208? I don't want to burn my barrel, but with the weight and higher BC the deflection in a crosswind is some 20% less than the 208 so at least on paper it looks amazing...
I guess we'll find out when you shoot the two boxes of choice ammunition 212s you just picked up 😂
 
Hope you don't mind me sharing a picture bro.
Choice Ammos 212 loaded to mag length at 2902 fps (factory data)

More to come as BT gathers some data on these
 

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No flex at all, what the grooves in the bullet sidewall do is remove bearing surface(the sides of the bullet that contact the rifling) and that lesser amount of contact/friction decreases the pressure because the bullet is easier to push out of the barrel. The bands can allow a heavier bullet to be shot faster than a lighter bullet that does not have the reliefs cut giving it more contact/friction with the barrel.
Notice the contact points from the rifling on this bullet and see how they only contact the high spots.... the groove reduce contact with the barrel = lower pressure which is longer barrel life. Or you can have equal barrel life but be able to shoot the bullets faster.View attachment 432482
Looks like there are two bands cut into it?
 
No flex at all, what the grooves in the bullet sidewall do is remove bearing surface(the sides of the bullet that contact the rifling) and that lesser amount of contact/friction decreases the pressure because the bullet is easier to push out of the barrel. The bands can allow a heavier bullet to be shot faster than a lighter bullet that does not have the reliefs cut giving it more contact/friction with the barrel.
Notice the contact points from the rifling on this bullet and see how they only contact the high spots.... the groove reduce contact with the barrel = lower pressure which is longer barrel life. Or you can have equal barrel life but be able to shoot the bullets faster.View attachment 432482
What kind of accuracy are you getting from these?
 
No flex at all, what the grooves in the bullet sidewall do is remove bearing surface(the sides of the bullet that contact the rifling) and that lesser amount of contact/friction decreases the pressure because the bullet is easier to push out of the barrel. The bands can allow a heavier bullet to be shot faster than a lighter bullet that does not have the reliefs cut giving it more contact/friction with the barrel.
Notice the contact points from the rifling on this bullet and see how they only contact the high spots.... the groove reduce contact with the barrel = lower pressure which is longer barrel life. Or you can have equal barrel life but be able to shoot the bullets faster.View attachment 432482
Also, does the bc hold true?
 
No flex at all, what the grooves in the bullet sidewall do is remove bearing surface(the sides of the bullet that contact the rifling) and that lesser amount of contact/friction decreases the pressure because the bullet is easier to push out of the barrel. The bands can allow a heavier bullet to be shot faster than a lighter bullet that does not have the reliefs cut giving it more contact/friction with the barrel.
Notice the contact points from the rifling on this bullet and see how they only contact the high spots.... the groove reduce contact with the barrel = lower pressure which is longer barrel life. Or you can have equal barrel life but be able to shoot the bullets faster.View attachment 432482
Thanks for the response.

To report a bit, I contacted Barnes about the bands and the LRX 212gr vs. the 208gr. They pointed out that the 212 grain has a smaller section of the bullet that rides on the barrel. that section is near the back of the bullet. The forward portion of the bullet is a slightly smaller diameter (not the nose or boat tail, but an actual long section of the center of the bullet) so it doesn't ride the bore and cause a pressure increase, according to the manufacturer. See the image they sent me with my own drawing on it. The green part is slightly smaller and the pink portion is what rides the barrel, giving it the "bore rider" name. Total surface area riding the barrel may be similar to the 208.

The also informed me that having the smaller section of the bullet that is actual 0.308" means you don't have as much adjustment in seating depth. Also, the 212 was originally designed for 300 Norma Mag. But can work in the 300 PRC. In some cases it may become a single feed cartridge, but I have some that fit my magazine.

I don't know what the expansion to the second section will do to the aerodynamics. I studies some subsonic aerodynamics in graduate school and subsonic it wouldn't be a problem, but supersonic flows are a different beast.

I also wonder whether or not the smaller portion riding the barrel on such on long barrel can fully control the concentricity of the bullet axis. The distance from the front of the bearing surface to the rear on the 208 is over 2x longer than the bearing surface on the 212 which means controlling concentricty of the axis would require less than half the force, and less than half the dimensional accuracy. So, would the tip of the 212 be vulnerable to wobble?


As LowDownDirtyBugger says I got some 212's from Choice Ammunition and when I can get primers I'll start learning to reload and try the 208 and 212 against each other.

Thanks again for the response and lessons learned.
 

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