Which bullets perform better post TS: Solids or Lead Core Jacketed?

[harry_x1]

Hi All,

I am trying to understand if anyone has done any study or based on their experience can make some educated guesses as to which type of bullets perform better past TS?

I understand there are various other pros/cons like splash on target, difficulty to tune, barrel life etc etc...but I am particularly interested in understanding if for a given caliber (let us say 300 grain projectiles for 338 caliber), will solids in general have better transition to sub sonic? For comparison purpose we can use 300 grain Berger OTMs vs 300 grain CE Lazers Gen2.


thanks for the inputs

Harjeet

 

[wvfarrier]

Solids in my experience since there is less deviation than the lead core

 

[Taylorbok]

not the ones that shoot 20" groups at 100. Others are having better luck with solids due to being more consistent
I feel you could have amended this to one of your other bullet threads.

 

[Dogtown]

I know you asked a kind of narrow question, but I feel like I need to preface an answer with a bit of context....


Solids are kind of a tricky thing to deal with at times and getting them to work is often a bit of a commitment, so my general rule of thumb: stick to jacketed lead bullets until you can reliably hit their limit, then look at solids.

Solids tend to be longer for comparable mass, so you either step down to a lower mass solid or get a faster twist barrel (1:9 is great for 300gr bullets, but you'll need to go faster for most solids >260gr). Also, some solids are really picky about bore specs and just won't shoot well in some barrels no matter how hard you try. Some also are very strict about where they need to be seated, etc - so they can be a lot of work.

That being said, solids by their nature of being monolithic and built on CNC machines, tend to be significantly more consistent than any jacketed lead bullet. And their manufacturing process means they can be made to fit a highly efficient aerodynamic design that is otherwise impossible with jacketed lead bullets, giving them impressive BCs.

To the question at hand:

But do they transition through the transonic zone in a more stable way than jacketed lead bullets? Generally yes, but not necessarily in a huge way these days, from what I've seen. Sure, 20 years ago things seemed quite different, but the quality of jacketed lead bullets for precision has really improved over the years. In the ELR matches I've shot in recent years, I've shot mostly jacketed lead bullets (.300NM & .338LM Improved 40) between 2000-2500 yards. However, I am also shooting solids in some cases, not because they transition better, but because the higher performance means they stay supersonic longer.

Case in point, I'm currently working on a 241 Seneca load with .300NM. While my 250 A-Tip load stays supersonic out to 2600 yards (at 3000' AGL), these solids at the same velocity will stay super sonic to 3100 yards.

 

[cameljockey230]

0.555 G7 in a 30 caliber bullet if true is amazing!!!

 

[Dogtown]

I haven't shot them at distance yet though...

Currently I'm trying to get a 1:7 twist 34" .300NM barrel to shoot them, but they're giving me headaches. I've got a different barrel on order as a backup so it may be a while before I can take these up the hill. Until then, it's trusty 250 A-Tips.

 

[GIXXER2000]

I run a 1-8 twist 300NM and have had no issues. When I talked with Robert Vestel about twist rates and solids vs lead core in my 375ct he said the 7 twist is to fast for the speed I was shooting. So you my have the same issue. I sure if you tried some solids they would work just fine in the 1-7.

 

[ForgeValley]

View attachment 8163172

I haven't shot them at distance yet though...

Currently I'm trying to get a 1:7 twist 34" .300NM barrel to shoot them, but they're giving me headaches. I've got a different barrel on order as a backup so it may be a while before I can take these up the hill. Until then, it's trusty 250 A-Tips.

That's a phenomenal G7 BC. If you get them to shoot, let us know!

 

[Dogtown]

I’ll know more tomorrow…

 

[cameljockey230]

DogTown if you get them to shoot and the 0.550 G7 holds true don't tell anyone but me.
Good luck buddy

 

[Rabbitslayer78]

I'm having some trouble finding data for a 1/7" twist rate in a 22" SSK barrel chambered in .309 JDJ . Was wanting to shoot 205 Berger or Eld-X. Can't find load data anywhere. I should have paid more attention to the twist when I purchased it. Thinking I could make it work. I mean they made it for a reason, correct? I contacted SSK, I was told I could shoot 150gr on up. Any help would be greatly appreciated.

 

[MojoNixon]

I'm having some trouble finding data for a 1/7" twist rate in a 22" SSK barrel chambered in .309 JDJ . Was wanting to shoot 205 Berger or Eld-X. Can't find load data anywhere. I should have paid more attention to the twist when I purchased it. Thinking I could make it work. I mean they made it for a reason, correct? I contacted SSK, I was told I could shoot 150gr on up. Any help would be greatly appreciated.

Give Berger a call, and ask your question and provide them with your email. My understanding is they are very good at giving info. I just received their 1st edition reloading manual but I’m stuck behind enemy lines in Commiefornia until late tomorrow and the manual is at home in the Reno/Sparks area.

 

[CoryT]

A smooth transition to subsonic flight is more a matter of bullet design and rate of spin rather than material. Where is the CP located in relation to the CG and how does it move as the Mach cone moves forward? Is the twist rate used resulting in a coning motion that does not sharply increase as the velocity decays?

During the 338 bullet tests here at Gunsite many years ago, we had conventional bullets that flew great right up to subsonic and solids that would make a sharp right turn and could not hit a car at 1500.

In short, everything now matters in a big way once you get way out there, no more margin for error of any kind.

My previous 375 CT barrel would shoot Warner Tool solids like a laser, the Cutting Edge and Lehigh solids would not group at even 100. The new barrel has a faster twist, the Warner bullets are still lasers, have no reason to try the others again. I may run some 390 A-Tips just for a mag length load, I tested some old Rocky Mountain 375gr jacketed which work well, but seem to be out of production.

 

[cameljockey230]

I'm having some trouble finding data for a 1/7" twist rate in a 22" SSK barrel chambered in .309 JDJ . Was wanting to shoot 205 Berger or Eld-X. Can't find load data anywhere. I should have paid more attention to the twist when I purchased it. Thinking I could make it work. I mean they made it for a reason, correct? I contacted SSK, I was told I could shoot 150gr on up. Any help would be greatly appreciated.

The 309 jdj has a touch more case capacity than a 30-06.
I would look for 30-06 load data and do some interpretation/extrapolation