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Who has 277 Fury load data.

The 277 Sig Fury is begging for a 25 Cal, 7.5" twist barrel and a 6.5 barrel!
I originally stated this build around this brass specifically for a second 260 AI.

Upon examining the 6.8×51 cartridge design and my current bullet inventory of unused 140 classic hunter Hybrids and 150 ABLR bullets sitting idle and happening upon dies i went the 277 Fury direction.
I have enough of these hybrid cases to form 243AI, 260AI, 308win later.

This cartridge design is optimal for its caliber and head size.20250802_131603.jpg
 
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I originally stated this build around this brass specifically for a second 260 AI.

Upon examining the 6.8×51 cartridge design and my current bullet inventory of unused 140 classic hunter Hybrids and 150 ABLR bullets sitting idle and happening upon dies i went the 277 Fury direction.
I have enough of these hybrid cases to form 243AI, 260AI, 308win later.

This cartridge design is optimal for its caliber and head size.View attachment 1682578
Hmmm??? In looking at your picture, it looks to me like that steel case head has pulled out some when you sized it. I don't know if that'll ever be a real issue. I got a case that looked like that when I felt and heard a little pop when pulling one out of my sizing die with a little more effort than usual, thinking I probably didn't use enough lube. On inspecting, I saw a little gap like that, which was different from all the other's I had already sized. I decided to set it aside and not use it since I have no idea how that change in the way the head fits to the body might be an issue or not.

Here is a pic showing the difference between that one the pulled out some (on the right) with a pop and one like the others that had no sizing issues (on the left):
Hybrid Case Head pulled out.jpg
 
Hmmm??? In looking at your picture, it looks to me like that steel case head has pulled out some when you sized it. I don't know if that'll ever be a real issue. I got a case that looked like that when I felt and heard a little pop when pulling one out of my sizing die with a little more effort than usual, thinking I probably didn't use enough lube. On inspecting, I saw a little gap like that, which was different from all the other's I had already sized. I decided to set it aside and not use it since I have no idea how that change in the way the head fits to the body might be an issue or not.

Here is a pic showing the difference between that one the pulled out some (on the right) with a pop and one like the others that had no sizing issues (on the
That is a virgin unsized case. All I did was seat a bullet.
 
20250803_140018.jpg
I sized some to 308 win. ( not a good idea with rotator cuff injury). I don't see a big difference in the transition junction.

Going to load up some 155gr with Benchmark.



I cant wait till my 277 barrel get here, I want to shoot some of these cases.
 
So I shot the Hybrid 308 cases the other day, I sized the cases with an small base die and it sized the steel web just like a brass case.
Yeah, after reading your post, I just sized one of my fired .308 cases for the first time after necking up with my standard Forster FL sizing die. Before sizing the steel web of the fired case measures .4690 and after sizing it measured .4675. :eek: I wasn't expecting that steel web to expand and size like that. It sized right back to what the cases are before necking up. :rolleyes:
 
Would sizing the steel web wear the inside of the die more?
Good question. Though I'm not sure what kind of "wear" we'd be talking about.

Steel work hardens faster than brass, so I'm not sure how this will play out with the particular hybrid case design. Will the steel begin to show signs of some fracturing after multiple cycles of firing and sizing??? I would think it would. . . eventually. As 46and2 said . . . "I guess we'll find out". ¯\_(ツ)_/¯

1754949693780.jpeg
 
Good question. Though I'm not sure what kind of "wear" we'd be talking about.

Steel work hardens faster than brass, so I'm not sure how this will play out with the particular hybrid case design. Will the steel begin to show signs of some fracturing after multiple cycles of firing and sizing??? I would think it would. . . eventually. As 46and2 said . . . "I guess we'll find out". ¯\_(ツ)_/¯

View attachment 1685130
I'm going to go ahead and say, we better FL size every time so it doesn't get (memory?) Out of control.
 
Eventually the die will show a Mark where the two meet.
Barnes TTSX 110 are a Hoot to Shoot.
And the 130 class will get you to 3000fps.
I haven't shot the 170 Hybrid yet.

And yes I'm hearing a lot of guys are necking up and down with the Hybrid case.
 
Barrels made of cheap less strong steel alloys; lack of stress relief or a good stress relief process; barrels produced with inconsistent quality controls in production. :rolleyes:
B.S. !!!!!!!!!!!!!!!!!

That was a pretty offensive statement you made and not knowing any of the details.

The ringing of the chamber with the hybrid cases cannot be stopped running the pressures at 80k psi so far from what I understand.

The ring will show up at the junction where the steel case head meets the brass body of the case.

Run the round at 65k and it behaves like everything else. Run it at 80k and things are going to change. No way around it.

Even Sig has told us our BB material stands up better to the abuse of 80k psi vs standard 416R and we have made them a ton of barrels for R&D as well as we make them a lot of ammunition test barrels. Both accuracy and pressure and velocity.

On production guns they are adding coatings and metal treatments to help with the ringing of the chambers to prolong service life.

I just love it when people say things and they have no clue as to what is going on!

Later, Frank
Bartlein Barrels
 
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Also QL data might put you in the ballpark when it comes to pressure but it does not replace actual pressure testing data! To an extent your still guessing.

Too many variables from powder to lots of powder to different lots and different brand of bullets as well as cases and not to even mention what chamber reamer spec a guy used along with from one barrel to the next on bore and groove sizes. All of these things can have a big impact on pressures.

That's why we made a actual pressure test barrel for actual load data and pressure testing for 7/6.5PRC. One guy says oh with this powder charge and powder my gun runs like a watch... but the next guy will post...oh I'm using the same powder and bullet but my gun runs fine with a +4gr heavier powder charge.

Sierra provided bullets for that test along with Hornady, Berger and I was supplied powder and brass cases and we made the pressure test barrel and Hornady ran the test for us. That was the only way to get hard data without guessing.
 

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