How long is long enough ?

[fiftybmg]

I follow with ambivalence the striving for longer bullets in tighter twist barrels, and notice the fad gets forgotten then resurrected periodically.

I do understand that longer bullets have higher sectional density. Other than that, what else do they have ? Bragging rights ? My twist is tighter than yours ?

You have a 6.5 caliber, and you fancy sending 180 grainers downrange. Or, you really need to go up to 250 grains in your .30 cal. No problem, new barrel, tighter twist.

No shortage of rifle builders to make that up for you, but why ?

If you're hung up on the bullet weight, why not just go one or two calibers larger ? Instead of 250 grains in 30-whatever, why not 245 grains in .375 ?

Yes, the BC. So the BC of the smaller caliber may be higher. Maybe. The velocity gain most likely cancels the BC loss.

Recoil ? You want less recoil ? Big bullets without recoil - a fascinating theoretical concept.

Accuracy ? Accuracy is a platform, not a bullet.

There are many advantages to running a rifle on the light side of the ballistics, and none to pushing the max - other than it being an itch to scratch, which seems to resurface as if it's something new again after skipping a generation.

The first, or one of the first - long-for-caliber bullets was chambered in the 6.5x55, in the 1890's . Slightly taller brother to the 6.5 Creedmoor.

 

[HARPERC]

I started out with a .30-06, and 14 rounds of 220 grain core-locts. Worked, great as my limits were somewhat less than the rifle and load. My reasons for not using that particular load these days is experience/education, and entertainment which I think most of us are in for. For most of what I like to do these days, that combination would be limiting me, not the other way around. Where's it written we can't just have fun?

The practical side all other things being equal I see the heavy for caliber bullets seem to penetrate better. The 6.5's made their bones with 160 grain round nose bullets. They work well in their range limits, but it's rare to see someone still using them. Must be somebody because ammo is still being made to duplicate it, but why not improve it's ballistic profile. Similar numbers exist for .308 (220) and 7mm (175), and others in your neck of the woods.

Once we get to bigger calibers on deer size targets, there aren't many loads that wont deliver adequate terminal performance. With todays big cases capable of driving bigger bullets as fast as some of the lighter bullets of the last few decades, why not take advantage when, and where it makes sense?

Lead bans are here, replacing them with copper while maintaining weight, we have to use longer bullets. Necessary gets debated.

Laser range finders, and ballistic programs make distance manageable, the enemy now is windage, and heavier performs better.

Lots of hunting these days is limited entry, and once in a lifetime, choosing cartridge bullet combo's that give one the ability to cover the greatest number of variables seems sensible. I've been applying for 20 years for an Oregon antelope, a 6.5x55, 1-8" twist, 156 grain traditional bullet starts at 2560 fps. Various 6.5 wildcats will likely launch the 156 Berger requiring a 1-7" twist 800-900 fps faster, with a high BC. Others fall in between. The 156 Norma has a G1 BC of 0.348, the Berger a BC of 0.679, length is. 1.29" to 1.512" Making in my opinion, the better choice for either cartridge on the high desert.

 

[fiftybmg]

The twist definitely need tightening for equivalent weight monos. A lot of people try monos at the same weight as their lead cores, and if they are already at the upper end of bullet weight, they find no accuracy and assume monos are a dud.

Roughly 20% depending on the exact alloy - for a 100 grain mono, you need a twist that stabilises a 120 grain lead core.

In the end, the bullet weight is similar, it's not a case of using over-weight bullets for caliber.

 

[WeiserBucks]

Your user name is fiftybmg and you're wondering why people want to use heavy bullets?

 

[HARPERC]

..it's not a case of using over-weight bullets for caliber....

When the military desires more hits at distance from a particular platform the simple fix has been to increase bullet weight. Moving from 190-220 grains in the .300 Winchester Magnum. 147-175 in the 7.62x51.

The bulk of .308 diameter early military ammo in the .30-40 Krag, and .30-06 were 220 grains. So much of what you're speaking of represents a return to what was originally standard bullet weight.

The change in thinking of volume fire not covering all situations, and selective marksmanship being an effective tool.

Perhaps not across the board, but certainly on this site the 215 Berger is likely the standard .300 Winchester Magnum load.

The increase in case capacity from the .300 Winchester to the .300 RUM, makes the step up similar to from the .308 Winchester to the .300 Winchester, opening possibilities, and a 245 grain Berger makes sense.

Improved optics, and other parts of the system, also improved, and effective range for selective marksman goes up.

The famous Billy Dixon shot has moved from the realm of legend, to something repeatable. Not a gimme, but something that has the wise opponent hunting cover. As the advances trickle back into the civilian realm, our games, and activities change to take advantage.

I love my .375, it shoots the 248 grain Hammer very well. Those wishing for next level performance from a .375 typically move to larger platforms, and again heavier projectiles.

From a long range hunting standpoint maintaining terminal velocity is essential. Bigger cases, and heavier bullets can provide this. Yes, depending on the case, muzzle velocity, game, and the range lighter bullets can be as effective.

I'm not particularly dogmatic in my personal use, and freely move back and forth through the choices.

 

[sp6x6]

I might try some downsizing,maybe for that rat deer or speed goat Currently

use 300,heres a 240 Dozier and berger 250

 

[fiftybmg]

Your user name is fiftybmg and you're wondering why people want to use heavy bullets?

It's not about bullet weight only, it's about pushing a cartridge to the point of ridiculousness when you can get better results easier by going up a caliber or two.

The Browning 50 has a slow twist, even for the longest match bullets.

When Mr Ackley put together the .22 Loudenboomer, he was aiming to break a speed record because he believed it could be done.

That's what it comes down to - wanting to put something together because it can be done, and not being too excited about what has been done already, even if it works better.

I'm all for tinkering, it is the foundation of innovation, without it there would be no variation and improvements.

Is a 6 twist an improvement ? Then a 5 twist ?

 

[HARPERC]

.....It's not about bullet weight only, it's about pushing a cartridge to the point of ridiculousness when you can get better results easier by going up a caliber or two...............That's what it comes down to - wanting to put something together because it can be done, and not being too excited about what has been done already, even if it works better.

.......I'm all for tinkering, it is the foundation of innovation, without it there would be no variation and improvements.

......Is a 6 twist an improvement ? Then a 5 twist ?.........

"Better results", and "works better" is a bit nebulous, but yes playing with the ballistics calculator will show some small fast bullets, outrun bigger BC numbers to a certain distance. If that works in your situation use it. I run 180 grain Accubonds in my .338 RUM at 3550 fps. A great mid range varmint load. A 100 yard antelope bullet-not so much. The splat factor is just to high.

We've been playing with a 6.5 Ultracat (6 twist), basically an improved RUM case. In previous use the powders weren't available to make it sing like it can today.

It's early to tell where the 6 twist fits, but ruling out a 5 twist without looking into it isn't something I'd do. Some interested shooter may come along with the right combination of cartridge, and bullet to bring it together.

My .375 was supposed to be a 1-10" twist, turns out it's like 1-11". Since then I've seen variations in twist aren't all that unusual when we start measuring them, and it may be prudent to lean a bit to the high side when ordering.