120 gr 6.5mm @ 4000fps?

[Dennis_in_VA]

I was wondering if anybody here could tell me if there is a round that can push a Nosler 120 gr 6.5mm Ballistic Tip around 4000 fps with a good degree of accuracy and without the bullet self destructing?

I see that Richard Franklin's 300 WSM Varminter will push a Hornady 110 gr VMax @ 4000 - 4100 fps with a slow twist barrel.

Would a 6.5X284 have the potential for pushing the 120 gr Ballistic Tip to 4000 fps using a long, slow twist barrel?

Let's hear what you have to say, I am all ears.

Thanks in advance for your input.

 

[k80skeet]

I have a 6.5 x284 and the best I seem to get is low 3000. I also Have a 264 Winchester Magnum and with 66.5 of H4831 about 3360fps and it is about 20 more grains of powder than my 6.5X284. So to answer your question no not possible.

 

[2506]

I am getting 3600 fps from my 264 Win mag with 65.0 grs H-4831 and 70.5 grs Retumbo with 120 BT's but my rifle has a 27 3/4' barrel.

 

[Asscott4]

Well you could neck down a .300 Ultra mag and I'm sure that you could achieve that velocity with a .264 bullet. But again that would prolly cost a lot and it prolly wouldn't be very accurate with the light bullets. but I would think it would be cool non-the-less!

 

[Dennis_in_VA]

Well I don't see why a 300WSM can do 4000 with a 110 Vmax and accurate to boot and 6.5-284 with a 120 BT can only get low to mid 3000.

What twist are you guys using.

Richard is using a 1-15 twist on his 300WSM.

So why wouldn't lets say a 1-12 work with the 6.5-284, since it appears the have the same general case capacity, right? Sure beats having to neck 30 cal to 6.5mm?

Or if I wanted to get really jiggy with it, maybe look into one of those Kirby Allen Magnums. He takes a 338 RUM and necks down to 6.5mm. I don't know much about it but he went with the 338RUM instead of the 7mm or 300RUM because of shoulder and feeding issues.

I know which ever route that is taken on the path to what I'm asking about, that one thing is certain. It will be an overbore barrel burner but it will be like a Dragster. Fast, Fun, and lots of Red Mist and Chunks.

 

[malcarjeb]

I have a 6.5 RUM with a 29' barrel and the best it will do is 3850 with the 120 BT. I have a 264 Win Mag that will do 3900 with a 100 BT. I have never tried the 100s in the 6.5 RUM. The 6.5 bullets will have a lot better BC than the 110 30s.

I have shot several whitetail deer with the 120 BTs in the RUM and it makes a mess!

 

[bohemR13]

With all else being equal, the larger bore bullet will go faster from a given case.

The reason is the bearing area and the pressure area on the bullet. That 120 6.5 bullet with the same bearing vs. pressure area ratio as a 110 30 bullet would probably be around 90 grains.

This trend is easy to see.

140 in a 260 Rem vs. a 140-150 in a 308
50Vmax in a 223 vs. 50 Vmax in a 6mm-223
180 in a 280 Rem vs. 180 in a 30-06
225 in a 30-06 vs 225 in a 338-06

 

[6Dasher]

So why wouldn't lets say a 1-12 work with the 6.5-284, since it appears the have the same general case capacity, right?

Not even close. The 284 holds about 15gr less powder than the WSM.

 

[6BRonwheels]

The capacity for the 6.5-284 is 67 grains of water, and the water capacity for the 300 WSM is 82 grains. That probably has a lot to do with the 6.5-284 not being able to do 4000 fps with that bullet weight. 15 more grains of powder is a lot of extra boom.

 

[k80skeet]

My 6.5X284 has a 1 in 8 twist. My 264 Winchester Magnum has a 1 in 11 twist. If you really have your heart set to have a 6.5 120gr bullet to go 4000fps get a Weatherby 30-378 neck it to 6.5 with 120grs of powder you should be able to make it no problem.

 

[Asscott4]

My 6.5X284 has a 1 in 8 twist. My 264 Winchester Magnum has a 1 in 11 twist. If you really have your heart set to have a 6.5 120gr bullet to go 4000fps get a Weatherby 30-378 neck it to 6.5 with 120grs of powder you should be able to make it no problem.

Haha that would be awesome but I woul dhave to say it woul dbe even more overkill than necking a .300RUM down to 6.5 like I said. But like you said if you really are wanting it then there is always a way to do it and either a .300RUM necked down or a .30-378 necked down would do the job. Now I wonder how long the barrel would last with that much poop behind a 120gr .264 bullet? If I had money to just burn I woul dtry it out and let you all know but I don't.

 

[bohemR13]

6.5-300 Kong? Why go for 4k when you can get to a mile a second...

A 264-378 Wby holds about 120gr of water, the 300 Kong is about 137 from what I've read. Just go with that and a 30' barrel, you can shoot to the next state.

 

[CJ6]

before you shoot your first shot get another barrel on order

 

[Asscott4]

Haha well this is true! To get these velocities you will always have a downside and that being barrel life! But hey it's just money right?!

 

[Spanners]

6.5-300 Kong? Why go for 4k when you can get to a mile a second...

A 264-378 Wby holds about 120gr of water, the 300 Kong is about 137 from what I've read. Just go with that and a 30' barrel, you can shoot to the next state.

Any more info on this case?
Whats its parent??

 

[MLC]

I have a 6.5 Rem Mag AI with a 30' barrel that has pushed 139 Lapuas just shy of 3500 fps.
I think with a 9 or 10 twist and 30' you could get 3700.
It would be a whole lot easier using the 95 VMAX or 100 grain Nosler.

 

[bohemR13]

The 300 Kong is a 30-378 Wby with a standard shoulder, blown forward with little body taper, it looks like a massive 300 WM with some changes to the shoulder angle.

The 6.5-300 Kong was something I just made up on the spot as a joke, but I'd envision it to be just necked down from there. I don't want to think about barre life since the 300 version is under 1000 rounds with 240gr pills going 3500 fps.

 

[Asscott4]

The 300 Kong is a 30-378 Wby with a standard shoulder, blown forward with little body taper, it looks like a massive 300 WM with some changes to the shoulder angle.

The 6.5-300 Kong was something I just made up on the spot as a joke, but I'd envision it to be just necked down from there. I don't want to think about barre life since the 300 version is under 1000 rounds with 240gr pills going 3500 fps.

Jeez! It's pushing a 240gr bullet at 3500fps?! Jeez now that a barrel burner if i've ever heard of one lol! Still sounds like fun!