.300 win mag barrel length and twist...

[Bravo 4]

Hook,
No arguing BC is a major part in down range performance (especially at longer ranges), no denying the "science". However it isn't the absolute. Velocity needs to be thrown in the mix as well. We both know the BC allows the bullet to maintain that velocity, thusly they work together to decrease time of flight. That's how you get less wind deflection. All I'm getting at is that there is a point to which a cartridge cannot push a bullet that is so long and heavy (high BC) and it "out do" one that may be a little lighter and faster. That works with all cartridges, even my .375 Snipetac. It's best performance is with bullets in the 375 (377) to 400 grain range. While there are bullets with much higher BC (such as the 452 grain Cutting Edge), it simply cannot push them fast enough to benefit. That's shooting out to 2000 yards.
I get what you are saying, here is an example I always use when explaining/comparing pure BC to pure velocity:
A 7mm RemMag will send a 140 grain soft point bullet around 3,200 FPS and a .308 can send a 215 Berger around 2600 FPS. At 600 yards and beyond I would take the .308 over the 7mag any day. The only place the .308 will not be superior is in drop.
Now what do you think the .308 could do when comparing the 215 and what has yet to be...the 245 grain Berger. I know-I know it's ridiculous as it isn't around, but I hope you see where I'm going with it.

 

[Capt RB]

Hook,

A 7mm RemMag will send a 140 grain soft point bullet around 3,200 FPS and a .308 can send a 215 Berger around 2600 FPS. At 600 yards and beyond I would take the .308 over the 7mag any day. The only place the .308 will not be superior is in drop.
Now what do you think the .308 could do when comparing the 215 and what has yet to be...the 245 grain Berger. I know-I know it's ridiculous as it isn't around, but I hope you see where I'm going with it.

What about the .8bc 230 sierria with it's shorter baring surface? You could possibly keep a bit more velocitiy with a bunch more bc vs the berger?
In my case I'll be running a 150 solid at 3090ish fps out of my 308 I haven't confirmed the bc but @ the .513 they give I'm shooting 1 1/2 moa high at 300yds furthest I've been able to shoot so far. I think once I can shoot prone and get a solid grip on the load I should be about 3110 with very good sd & ES. These are danzac coated and my barrel runs fggm about 120fps faster than the box states 2714-2732 depending on the lot#

 

[NEMTHunter]

In all honesty I am not sure I would consider the 230smk for big game hunting. The hollow point is so small that I am not sold on it working yet.

I have a feeling they are only going to be good for target at long range. the slower it goes the less likely it will open up.

 

[Capt RB]

In all honesty I am not sure I would consider the 230smk for big game hunting. The hollow point is so small that I am not sold on it working yet.

I have a feeling they are only going to be good for target at long range. the slower it goes the less likely it will open up.

I'm not going to use it for that Just as a for instance case. I know the 183's shed the nose and rip apart coyotes. Only experience I have with the new javelins Sierria is making

 

[WildRose]

The sooner you take a bullet out of yaw the more consistent it flies. Only way to do that is twist rate. Run the berger stability calculator and you will see increasing the velocity has a minor effect in the stability factor. Increase the twist rate and the number jumps. Over spinning the bullet without blowing it up will increase the bc of that bullet. It will also improve the transonic predictability for a firing solution.
Ruger and Browning are offering a 9tw from the factory as of today. An 8tw in the 300win would be optimum for the heavy solids and the new 230 Sierria's. The 245 Bergers Idk about yet but it would seem they will like the faster twist. But they would also benefit from a bigger case like the rum or .590 case head cartridges.

I'm not sure where you getting the need for the 8tw for the 230. There's no reason the 9 twist would not fully stabilize it.

 

[Capt RB]

I'm not sure where you getting the need for the 8tw for the 230. There's no reason the 9 twist would not fully stabilize it.

It's what they suggest for twist rate. I have to use that where I shoot due to being less than a mile from the ocean for my local range. I'm sure If I shoot up at Mom's house I might get away with a 9tw. At 2000' in typical weather I shoot in It would still not be optimum if you use the Miller twist rule. Now if you wanted to shoot the huge hammers a 9 won't work for me at all.
For example I have 95ish 150grn 6.5 mk's left because of this. In my 8tw savage At a velocity of 2890fps I could not get them to shoot point on. You could see the tear in the target at 100yds. I was told that the bto was the same as the 142's for a starting point. These bullets are really consistent in measuring them for 3 calibers. You just need to twist the crap out of them and your good to go.
Hunting bullets I'd say no but the 183's (only bullet I've shot in proper twist) worked well on the coyote shot. Chest hit and tore a 8" or so gash out his belly removing his manhood completely. Maybe 3 wags of the tail if that after the shot.

 

[Saracen]

Well I am sure all of us have been caught out before because we did not know what we did not know! I once bought a rifle chambered in .243 and then found out I could not shoot the VLD target rounds I wanted to shoot. Latter when I looked into it more I found out that no one at the time produced a factory rifle that would handle those your only option was to build your own. A lot of factory rifles are terrible in that regard. There is no reason to be using twist rates today that do not support the VLD bullets on the market. I have always thought you should be able beat the CEO of a gun company over the head with their product when they do mind numbingly archaic things like build and sell a rifle in 308 Win with a twist or 243 Win with 1:9. It like they have an IQ bellow 83 or they are living under a rock for the past 20 years. You know they have to be retooling regularly which means they could make a change at that time and incur no additional cost above the existing cost of retooling.

I have never understood why factories do not build what we really want to buy and we all keep buying it anyways!

My first 300 Win Mag was a Browning A-Bolt with Boss. I was 1 year out of high school and away at college. I am 45 now so that was a long time ago. The heaviest bullet most where shooting was SMK 190gr. but today that is not even considered a heavy load.

https://www.americanrifleman.org/articles/2017/5/24/unsung-hero-the-mk-248-mod-1/

I've got a rebarreld 300 Win Mag Remington Sendero with a 1 in 8 twist, and have high hopes for the 240 SMK a d RL 26.

 

[NEMTHunter]

I've got a rebarreld 300 Win Mag Remington Sendero with a 1 in 8 twist, and have high hopes for the 240 SMK a d RL 26.

I hope you have a lot on hand or a good place to get them. Sierra dropped the 240SMK Bullet. They quit making it.

 

[jshepherd61]

Hook,
No arguing BC is a major part in down range performance (especially at longer ranges), no denying the "science". However it isn't the absolute. Velocity needs to be thrown in the mix as well. We both know the BC allows the bullet to maintain that velocity, thusly they work together to decrease time of flight. That's how you get less wind deflection. All I'm getting at is that there is a point to which a cartridge cannot push a bullet that is so long and heavy (high BC) and it "out do" one that may be a little lighter and faster. That works with all cartridges, even my .375 Snipetac. It's best performance is with bullets in the 375 (377) to 400 grain range. While there are bullets with much higher BC (such as the 452 grain Cutting Edge), it simply cannot push them fast enough to benefit. That's shooting out to 2000 yards.
I get what you are saying, here is an example I always use when explaining/comparing pure BC to pure velocity:
A 7mm RemMag will send a 140 grain soft point bullet around 3,200 FPS and a .308 can send a 215 Berger around 2600 FPS. At 600 yards and beyond I would take the .308 over the 7mag any day. The only place the .308 will not be superior is in drop.
Now what do you think the .308 could do when comparing the 215 and what has yet to be...the 245 grain Berger. I know-I know it's ridiculous as it isn't around, but I hope you see where I'm going with it.

Will take my 7mm STW over any 30 cal even my 30-378. 7STW is pushing a Berger 195gr EOL at 3,278 fps. My 30-378 is pushing the 210 gr at 3,300 plus but also watches the 7mm 195 gr walk right past it at 1,200 yds

 

[NEMTHunter]

How about a 230 Hybrid @ 3367?

 

[Bravo 4]

Will take my 7mm STW over any 30 cal even my 30-378. 7STW is pushing a Berger 195gr EOL at 3,278 fps. My 30-378 is pushing the 210 gr at 3,300 plus but also watches the 7mm 195 gr walk right past it at 1,200 yds

That sounds like a screaming load from your 7 STW, I'm sure it does perform. I'm also aware it would beat the larger cartridge/caliber when the larger is loaded with a ballistically inferior bullet. If the velocities are similar then the higher BC is gonna win.

 

[Saracen]

I hope you have a lot on hand or a good place to get them. Sierra dropped the 240SMK Bullet. They quit making it.

My mistake, I meant to say 230 SMK.

 

[NEMTHunter]

My mistake, I meant to say 230 SMK.

The 230SMK should do well. It has a short bearing surface. Its just a little bit longer then the 215 Berger hybrid. It will make a great LR target Bullet.

 

[Saracen]

The 230SMK should do well. It has a short bearing surface. Its just a little bit longer then the 215 Berger hybrid. It will make a great LR target Bullet.

I've got my rifle back, with its 1 in 8 twist, and I know 71.5 grains of H1000 in an RWS case with a Federal 215 Magnum primer, shows no over pressure. Working up from there....