ELDMs Blowing up mid flight

[hoffbill]

it is not the speed it is the RPM along with barrel heat and wear.

Right on. Velocity and twist rate must both be considered. At some rpm, depending on bullet construction, they will begin to deform and disintegrate due to centrifugal force.

 

[L.Sherm]

8 twist is not fast enough for the heaviest badlands bulldozer bullets it's fine for the 195

Thats exactly why I suggested 195's

 

[Calvin45]

My 28 nosler has approximately 120 round down the tube as of today. Its a 26" proof 1:8. The first 100 rounds did well, mainly for load development, zeroing, etc. I've been using 1 box of Hornady 180 ELDMs (just opened a new box for these last 20 rounds), N570, with ADG brass. My 180's are from several different lots (tough times finding bulk supplies).
As of now, my load with 82 gr of N570 is pushing the 180's to 3130 fps.
Today at my local range I was finally setting the zero stop on my scope. These rounds were with the new box of 180 ELDMs. First 3 rounds were fine, made and adjustment, then I get this on the target, 3 inches high, when I have yet to touch the elevation:
View attachment 298557

At first, I thought the bullet just tumbled. Well, it did tumble, but it was also coming apart. Upon closer examination, you can see the gray marks on the paper when part of the jacket impacted the paper, with a shape that is not just a tumbling bullet. Started to think well, may be it was due to me recently stripping down the barrel and just shrugged it off.

Went 5 for 5 with no issues. Even let the barrel get rather warm during that string too. It was fine. Then the next 3 groups of 3 had issues, with at least 1 round going way off target and never making the paper. I had a friend observe the impacts as well.

I was lucky enough to catch another separation on paper. This one you can clearly see the gray marks on the paper where the deformed jacket was striking the paper.

View attachment 298559

Has anyone else had this problem? I've read about 28 noslers having ELDMs blowing up completely when speeds exceed 3200 fps. I'm also aware that QA/QC has probably gone down the drain too, given the state of the industry.
With this experience, the expense to shoot this rifle, and me needing to have it dialed in before November, I ordered 150 rounds of 177 gr hammer hunts. At least with solids the odds of them coming apart are slim mid flight.

Bummer!!!! With the bc on that 180 eldm I figured a really fast 7mm with those would be pretty hard to beat trajectory-wise.

 

[TheLongRanger83702]

My 28 nosler has approximately 120 round down the tube as of today. Its a 26" proof 1:8. The first 100 rounds did well, mainly for load development, zeroing, etc. I've been using 1 box of Hornady 180 ELDMs (just opened a new box for these last 20 rounds), N570, with ADG brass. My 180's are from several different lots (tough times finding bulk supplies).
As of now, my load with 82 gr of N570 is pushing the 180's to 3130 fps.
Today at my local range I was finally setting the zero stop on my scope. These rounds were with the new box of 180 ELDMs. First 3 rounds were fine, made and adjustment, then I get this on the target, 3 inches high, when I have yet to touch the elevation:
View attachment 298557

At first, I thought the bullet just tumbled. Well, it did tumble, but it was also coming apart. Upon closer examination, you can see the gray marks on the paper when part of the jacket impacted the paper, with a shape that is not just a tumbling bullet. Started to think well, may be it was due to me recently stripping down the barrel and just shrugged it off.

Went 5 for 5 with no issues. Even let the barrel get rather warm during that string too. It was fine. Then the next 3 groups of 3 had issues, with at least 1 round going way off target and never making the paper. I had a friend observe the impacts as well.

I was lucky enough to catch another separation on paper. This one you can clearly see the gray marks on the paper where the deformed jacket was striking the paper.

View attachment 298559

Has anyone else had this problem? I've read about 28 noslers having ELDMs blowing up completely when speeds exceed 3200 fps. I'm also aware that QA/QC has probably gone down the drain too, given the state of the industry.
With this experience, the expense to shoot this rifle, and me needing to have it dialed in before November, I ordered 150 rounds of 177 gr hammer hunts. At least with solids the odds of them coming apart are slim mid flight.

Trying to shoot a 180 gr. bullet through a 1:8 twist seems much too fast. The 120 gr. are suited for the 1:8 twist rate. My experience has those heavier projectiles shot with a 1:10 twist is more the norm. If your lands cut deep into the copper jacket it seems reasonable that these heavier bullets are in fact shedding their copper jackets from this barrel in flight with the 1:8. Just my $.02.

 

[dougduey]

This is why I've preached on here no point in spinning a bullet no more than necessary.

My gunsmith preaches the same thing. He's also a Hall of Fame benchrest shooter, so I intently listen when he makes statements like this.

 

[Betarider]

pretty common.

the 147s out of my 1-7.5 PRC did it quite often once the throat wore and barrel heated up

I could often see the cloud that was the bullet as my 25-06 would run 3350 fps with Noslar 100gn. Ballistic tip. Mine never made it to the target but instead left little pieces all along the flight path.

 

[Patrick Gauthier]

My 28 nosler has approximately 120 round down the tube as of today. Its a 26" proof 1:8. The first 100 rounds did well, mainly for load development, zeroing, etc. I've been using 1 box of Hornady 180 ELDMs (just opened a new box for these last 20 rounds), N570, with ADG brass. My 180's are from several different lots (tough times finding bulk supplies).
As of now, my load with 82 gr of N570 is pushing the 180's to 3130 fps.
Today at my local range I was finally setting the zero stop on my scope. These rounds were with the new box of 180 ELDMs. First 3 rounds were fine, made and adjustment, then I get this on the target, 3 inches high, when I have yet to touch the elevation:
View attachment 298557

At first, I thought the bullet just tumbled. Well, it did tumble, but it was also coming apart. Upon closer examination, you can see the gray marks on the paper when part of the jacket impacted the paper, with a shape that is not just a tumbling bullet. Started to think well, may be it was due to me recently stripping down the barrel and just shrugged it off.

Went 5 for 5 with no issues. Even let the barrel get rather warm during that string too. It was fine. Then the next 3 groups of 3 had issues, with at least 1 round going way off target and never making the paper. I had a friend observe the impacts as well.

I was lucky enough to catch another separation on paper. This one you can clearly see the gray marks on the paper where the deformed jacket was striking the paper.

View attachment 298559

Has anyone else had this problem? I've read about 28 noslers having ELDMs blowing up completely when speeds exceed 3200 fps. I'm also aware that QA/QC has probably gone down the drain too, given the state of the industry.
With this experience, the expense to shoot this rifle, and me needing to have it dialed in before November, I ordered 150 rounds of 177 gr hammer hunts. At least with solids the odds of them coming apart are slim mid flight.

 

[L.Sherm]

The 120 gr. are suited for the 1:8 twist rate.

Huh, misprint? A 1-9 is more suited for a 180 in a 7mm

 

[Patrick Gauthier]

Tumgling closer 600yards dose not make sense. With a twisted rate 1/8 it should have enough rotating speed to stay straight aligned to hit the target and led a defined round cut.

Did you measured few of the bullets make sure the diameter is right?
What about the speed out of the barrel? Constant? In the rang expected or below?

Looks like gap between the bullet and the barrel?!?!?

Regards

 

[skipglo]

My 28 nosler has approximately 120 round down the tube as of today. Its a 26" proof 1:8. The first 100 rounds did well, mainly for load development, zeroing, etc. I've been using 1 box of Hornady 180 ELDMs (just opened a new box for these last 20 rounds), N570, with ADG brass. My 180's are from several different lots (tough times finding bulk supplies).
As of now, my load with 82 gr of N570 is pushing the 180's to 3130 fps.
Today at my local range I was finally setting the zero stop on my scope. These rounds were with the new box of 180 ELDMs. First 3 rounds were fine, made and adjustment, then I get this on the target, 3 inches high, when I have yet to touch the elevation:
View attachment 298557

At first, I thought the bullet just tumbled. Well, it did tumble, but it was also coming apart. Upon closer examination, you can see the gray marks on the paper when part of the jacket impacted the paper, with a shape that is not just a tumbling bullet. Started to think well, may be it was due to me recently stripping down the barrel and just shrugged it off.

Went 5 for 5 with no issues. Even let the barrel get rather warm during that string too. It was fine. Then the next 3 groups of 3 had issues, with at least 1 round going way off target and never making the paper. I had a friend observe the impacts as well.

I was lucky enough to catch another separation on paper. This one you can clearly see the gray marks on the paper where the deformed jacket was striking the paper.

View attachment 298559

Has anyone else had this problem? I've read about 28 noslers having ELDMs blowing up completely when speeds exceed 3200 fps. I'm also aware that QA/QC has probably gone down the drain too, given the state of the industry.
With this experience, the expense to shoot this rifle, and me needing to have it dialed in before November, I ordered 150 rounds of 177 gr hammer hunts. At least with solids the odds of them coming apart are slim mid flight.

I shoot them and 5 friends I load for...6 5 , .300 Weatherby, 338 lapua ....never seen that yet!

 

[chav0_12]

Trying to shoot a 180 gr. bullet through a 1:8 twist seems much too fast. The 120 gr. are suited for the 1:8 twist rate. My experience has those heavier projectiles shot with a 1:10 twist is more the norm. If your lands cut deep into the copper jacket it seems reasonable that these heavier bullets are in fact shedding their copper jackets from this barrel in flight with the 1:8. Just my $.02.

The 1:8 might be a tad too fast, it's not much too fast. Something between 1:8 and 1:9 would be ideal, a 1:10 would have no chance at stabilizing a 180gr 7mm bullet. The 1:8s are best in the over 180gr range for the VLD cup and core bullets.

 

[L.Sherm]

The 1:8 might be a tad too fast, it's not much too fast. Something between 1:8 and 1:9 would be ideal, a 1:10 would have no chance at stabilizing a 180gr 7mm bullet. The 1:8s are best in the over 180gr range for the VLD cup and core bullets.

Then what's the O.P's problem?

 

[chav0_12]

Then what's the O.P's problem?

Crappy bullets

 

[chav0_12]

Then what's the O.P's problem?

Or I should say crappy choice in bullets. I also did say that somewhere between 1:8 or 1:9, so 1:8 is probably too fast. Plus it seems like the ELDs weren't meant to be shot that fast. It sounds like guys are having success with that bullet in anything from 1:8.75 to 1:8.25. Perhaps if the 180 was slowed down below 3k FPS in the 1:8 it might be fine, just the wrong bullet in the wrong barrel sounds like.