22 CAL 90GR VLD Bergers Tumbling

[SidTheKidd]

I have an interesting situation with my 22-243 win. I was hoping to shoot the 90gr VLD out of my gun. The gun has a 1:7 twist. Which is what Berger recommends. I was shooting the 90gr VLD with a charge of 44 grn retumbo. I managed to chronograph them before they started tumbling and was getting around 3175 fps.
The bullets that I was shooting were a pretty old batch of 90gr VLD's. Lot # 000827 to be exact. Are these bullets different in some way from the newer ones? I have a unopened box of new 90 grn VLD's Lot # 3166. Wondering if it would be worth it to try them too?

Does anyone have a suggestion on why they would be tumbling out of the gun?

The gun shoots 80 Amaxs really well 5 shot group in the .5's with a velocity of 3350 fps.

Thanks in advance.

 

[loaders_loft]

you should contact berger on monday and see what they say

 

[DZelenka]

About 5 years ago a number of us shot 90 gr JLK VLDs out of service rifles and match rifles. Even with .22 BRs, we always used a 1:6.5" twist to stabilize them. I know that Berger says that 1:7" is the minimum, but no one that I knew shooting the 90s ever had luck with a twist that slow.

Dan

 

[backwoods83]

Slow em down to about 3050fps and give it a try.

 

[Mikecr]

backwoods is all over it.
Your twist is fine, but your energy/RPM's exceed the bullet's integrity. It's falling apart.

Reduced velocity or newer Bergers(thicker jackets) would probably fix it.

 

[SidTheKidd]

Yeah I was wondering if the newer 90 VLDs have a thicker jacket. I know that the ones that I loaded were pretty old. Did they change them since the 90 VLDs came out?

I kinna want to keep my speeds up as high as I can go. I like the grouping and speed that I am getting with the 80 Amaxs, plus I think that I can go faster with them...3450ish.

The 90 VLDs going 3200 with a BC of 550 would be pretty awesome ballistically, which is what I am shooting for out of this gun.

Thanks for all the replys already,
Sid

 

[Mikecr]

How bout an experiment we can all learn from?
Incrementally download with your old VLDs.
Backwoods is thinkin they'll hold together at ~3050fps, I think ~3015fps.
Show us the velocity where failures consistently stop.

Then,
Incrementally upload with new VLDs, same thing in reverse.

This will tell us how well Berger's recent efforts payed off.

 

[SidTheKidd]

I will try that...I am just waiting on some more Lapua brass. Right now I just have about 10 pieces.

 

[BryanLitz]

I think this thread is on the right track.

Your old lot is before we started making the target bullets on thicker jackets, so you're probably experiencing failure.

The new bullets on the thicker target jackets should hold together and stabilize fine out of a 1:7". The 1:6.5" may be required for the slow MV's of a 20" barreled .223, but the velocities your'e getting from the .22-.243 are more than enough to stabilize the bullet from a 1:7".

Please post your results with the new bullets.

-Bryan

 

[SidTheKidd]

I will try them out fellas. Thanks.

I should get the brass tuesday and will post the results as soon as i get loaded up for it.

 

[Kiwi Greg]

I have a 22-243 with 1-7 & shoot the 90 Berger at around 3100 with 2217/H1000.
It shoots mint sub 1/2moa way out there
If I shoot too many at a time & the barrel gets hottish, it is too much for the pills & they disentegrate mid flight.

I will check the box number

Box number PN 22423 Lot#1346

 

[SidTheKidd]

My gun seems to be making bullets disappear.
I had to slow the 90's all the way down to around 3000 fps before they stayed together.

Not sure whats going on?

 

[eddybo]

One of my 22x47 Lapuas will push them to 3300 without disintegration, unless you plan on firing more than 10 shots. My 8 twist 22x47 will not stabilize them even at 3300 fps, a 7 twist at those velocities blows them up, even the target bullets.

One thing about the 22 90gr bullets, they kick butt in a 223.

6mm 115s blow up, 7mm 180s blow up, 22 90grs blow up, 300gr 338s have problems, but none of these at normal velocities. Too bad many long range shooters like extreme velocities. We just try to use them beyond their designed parameters I guess. When they are working they work well, and they do kill stuff.

 

[Kiwi Greg]

I tried Retumbo instead of my H1000 & got more speed up to 3400 ish but the 90s couldn't cope.
I will do some more testing & drop the velocity back.
I have a few more loaded with H1000 & will fire them this weekend at a medium LR shoot.
The H1000 pushes them nicely at 3100 ish, very accurate, but we all like more speed

I would say your barrell twist combination is too hard on the 90s, I HBN coat my ones, that may make a difference ????