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Goodbye 6.5 Needmore-😎

Yes with an alloy case to handle the pressure that we aren't sure can be reloaded? It's a bit odd. Impressive posted velocities for shorter barrels though.


The velocity from short barrels with suppressors seems to be the selling point.


It holds no appeal to me but if other people dig it then good for them.


Basically a new cartridge and new technology for people to whine about, nothing new, lol. It's not like they cancel old cartridges when they develop new ones.
 
80k psi
16" barrel
Side port brake


Homies on the other benches


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I have pressure trace equipment and have done extensive testing on sml's. I have long range sml's that run pressures in the upper 60kpsi to lower 70kpsi range. Everything has to be right. Gas cutting can occur and you dont want anything to do with that. Our ignition modules are made of aluminum nickel bronze, which is much more durable than yellow brass that rifle cartridges are made of. For loads on the high end of that pressure range, we use modules that are modified grade 9 steel aircraft screws. The Pic below is one that failed. The pressure trace went off the scale at 113kpsi and the 1.385" barrel was bulged. Before I'll buy into this new gun, I'll go brassless first. It's safer.

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I have pressure trace equipment and have done extensive testing on sml's. I have long range sml's that run pressures in the upper 60kpsi to lower 70kpsi range. Everything has to be right. Gas cutting can occur and you dont want anything to do with that. Our ignition modules are made of aluminum nickel bronze, which is much more durable than yellow brass that rifle cartridges are made of. For loads on the high end of that pressure range, we use modules that are modified grade 9 steel aircraft screws. The Pic below is one that failed. The pressure trace went off the scale at 113kpsi and the 1.385" barrel was bulged. Before I'll buy into this new gun, I'll go brassless first. It's safer.

I was skeptical before based on the 6.8x51 (aka .277 Fury) design and multiple calibers that have fizzled out in the past 15 years (.30 Remington AR, .30 SuperCarry, and I am afraid to say the 6.8 Western). This press release made me pucker up yesterday when I read it. Now I am in full "hell no" mode based on this scientific data. Thank you
 
I have pressure trace equipment and have done extensive testing on sml's. I have long range sml's that run pressures in the upper 60kpsi to lower 70kpsi range. Everything has to be right. Gas cutting can occur and you dont want anything to do with that. Our ignition modules are made of aluminum nickel bronze, which is much more durable than yellow brass that rifle cartridges are made of. For loads on the high end of that pressure range, we use modules that are modified grade 9 steel aircraft screws. The Pic below is one that failed. The pressure trace went off the scale at 113kpsi and the 1.385" barrel was bulged. Before I'll buy into this new gun, I'll go brassless first. It's safer.

View attachment 260708View attachment 260709View attachment 260710
2 bullets? What caused so much pressure?
 
2 bullets? What caused so much pressure?
It happened at an sml competition shoot where I was pressure testing requested loads. I allowed a club elder to load my purpose built pressure test gun. Those of us who were there believe he put in a double charge of the booster powder. Im quite sure it was a single main charge. It was definitely a single bullet as I observed it being loaded. Needless to say, we did not try to duplicate it. That charge is called duplexing. It was done primarily before lrmp and direct ignition systems came on the scene. This club elder was still duplexing.
 
Basically a .280AI loaded.to 80,000 PSI.

Can't wait for folks to handload with brass cases and stick them in their chambers
I sure hope they make design changes that make the cartridge unique so it can't be chambered in a gun not designed for it.

That's what Marlin did when they came out with the 450 Marlin. It was to replace the 45-70 at higher pressures and they re-designed it so that it couldn't be chambered in a 45-70
 
I sure hope they make design changes that make the cartridge unique so it can't be chambered in a gun not designed for it.

That's what Marlin did when they came out with the 450 Marlin. It was to replace the 45-70 at higher pressures and they re-designed it so that it couldn't be chambered in a 45-70
I think the shoulder on the 7 backcountry is just a hair forward from the 280AI.

I guess the concept is the complete opposite of most newfangled longer range rounds... to burn a much faster powder in a very short barrell which creates a massive pressure spike, yet burns completely in a 16in bbl, as opposed to stuffing a case with the slowest powder you can burn in mod to long barrels to gradually build pressure with velocity.


But if you arent a handloader... the concept for an ultra compact rifle pushing the 168 Barnes LRX at 3000+ fps does have quite a bit of appeal.

But 80k PSI... that makes me uneasy!
 
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