A Theoritical Cartridge.... 6x 44.45 Rigby cartridge

[ConnorExum]

I'm looking for the maximum load density for the new 117DTAC bullets so I can get a velocity of about 3250-3300Fps which should maintain supersonic velocities out to 1720yards... What I'm thinking will do it is a 416 Rigby Case cut down to 1.75 inches in length and 40 degree shoulder I think could be the answer. It should have a diameter to length ratio similar to a 30Br and powder capcity of similar to 243AI or 6mmAI. Figure it should have about 50-60grains capacity in powder. Of course I'd like smaller primer pocket but that just isn't possible using the cartridge?

Any thoughts on the subject...

Perhaps the bigger Pegasus Cartridge would work better? I'm not sure right now this is in the pure paper stage but I think it has some potential? I know some work as been done with the 416rigby in the 6mm ranges but i'm not sure how much or what the results were it could I'm retreading old bad ideas or breaking new ground I don't know... I would nice to use a flash tube in the cartridge as well.

 

[bgjohn]

Y
JM

 

[chrisj]

you probably could do 3200 fps in a 243 WSSM Ackley with the shoulder moved fwd.

Chris

 

[Cheechako]

Connor

I have to agree with JMs question - Why?

You can probably get 3200 to 3300 out of a 6mm/06 and for sure out of a 6mm/06 Improved. With a long barrel, it's achievable out of a 244 Ackley. Or a 6/284. There are lots of options better than what you're contemplating. JMHO

Ray

 

[stuball]

I say build it. If it works for you then good for you. New wildcat, Isnt that how new things are made. Even though something may replicate another cartidge why shoot down the mans wanting to build a new to him and possibly us wildcat. I understand that there are other rounds that can do what he wants but I also see this guy wanting to build a new cartridge.
Sorry that is my 2 cents.

 

[ConnorExum]

Connor

I have to agree with JMs question - Why?

You can probably get 3200 to 3300 out of a 6mm/06 and for sure out of a 6mm/06 Improved. With a long barrel, it's achievable out of a 244 Ackley. Or a 6/284. There are lots of options better than what you're contemplating. JMHO

Ray

That's exactly what I want to do is attempt to replicate the velocities of a 6-06 AI but with benefits of a brenchrest cartridge... From all that I've read about the combustion of powder in a specific volume the best way to achieve the greatest efficiency and consistency in pressures is use a volume that has a greater diameter to length ratio with a sharp shoulder of about 30-40 degrees. So I figure is that I'm going to acheive maximum load density by reducing the cartridges' length to 1.75 inches overall and compressing the load into small capacity cavity to increase efficiency and consistency.

The question is can it be done?

 

[ConnorExum]

I say build it. If it works for you then good for you. New wildcat, Isnt that how new things are made. Even though something may replicate another cartidge why shoot down the mans wanting to build a new to him and possibly us wildcat. I understand that there are other rounds that can do what he wants but I also see this guy wanting to build a new cartridge.
Sorry that is my 2 cents.

What I want to know is am I barking up the wrong tree? Has research in this area been done before. The only cartridge I've heard of working in the 6x416rigby is the 6mm Thermos Bottle and it had about 30-32grain powder capicity I want to double that almost to duplicate 6-06AI but maintain the performance ie the inherent accuracy of smaller bench rest cartridges it might be impossible but I would like to attempt to do it.

 

[bgjohn]

If you want to shoot things a mile away get a gun that shoots a .50 BMG round.
JM

 

[ConnorExum]

If you want to shoot things a mile away get a gun that shoots a .50 BMG round.
JM

I don't want to shoot things a mile away... I want to create a very accurate 6mm cartridge that performs like 6-06AI. It can shoot a mile that is fine with me too but the goal is to reduce the produce the optimal cartridge for 1000 yards.

 

[bgjohn]

1720 yards is only 40 yards less than a mile.
JM

 

[ConnorExum]

1720 yards is only 40 yards less than a mile.
JM

Yes, but goal isn't shoot out there I was just showing the potential for cartridge to maintain supersonic velocities out ot nearly a mile. I want to really work in the 0-1500 yard range of the envelope. Mostly 1000 yard range. But if I increase the performance at 1000 yards than of cours the maximum supersonic range is going to increase to almost model but the goal isn't necessarily a 1-mile rifle.

 

[Cheechako]

Connor

My earlier post was certainly not meant to discourage you from pursuing your idea. I'm a wildcatter myself and have 4 different wildcat rifles that I use for long range benchrest. I don't think I've fired a shot at LR Benchrest with a factory cartridge.

I know that there is a popular theory that the short fat cartridges will perform better,more efficient and more accurate) than the long skinny ones but I"m beginning to think that it is a myth, especially at long range. I see more and more matches being won with old standbys like the 300 Ackley Magnum, 244 Ackley, and, yes, even the 6mm/06 and 6.5/06. Enough to make me think that maybe the short fat craze has run its course. Many of the radical ideas touted just a couple of years ago, such as the SMC and Thermos Bottle cartridges, seem to have died on the vine.

It's probably true that short and fat may be easier to develop a good load, as in the 6PPC, but anyone willing to spend the time in load development can probably do just as well with cartridges like the 222 and 6x47.

Developing a new wildcat such as you are proposing is not going to be cheap. My only suggestion is to look at some of the older cartridges that will do the same thing ballistically, before leaping.

Good Luck with your project.

Ray

 

[ConnorExum]

Connor

My earlier post was certainly not meant to discourage you from pursuing your idea. I'm a wildcatter myself and have 4 different wildcat rifles that I use for long range benchrest. I don't think I've fired a shot at LR Benchrest with a factory cartridge.

I know that there is a popular theory that the short fat cartridges will perform better,more efficient and more accurate) than the long skinny ones but I"m beginning to think that it is a myth, especially at long range. I see more and more matches being won with old standbys like the 300 Ackley Magnum, 244 Ackley, and, yes, even the 6mm/06 and 6.5/06. Enough to make me think that maybe the short fat craze has run its course. Many of the radical ideas touted just a couple of years ago, such as the SMC and Thermos Bottle cartridges, seem to have died on the vine.

It's probably true that short and fat may be easier to develop a good load, as in the 6PPC, but anyone willing to spend the time in load development can probably do just as well with cartridges like the 222 and 6x47.

Developing a new wildcat such as you are proposing is not going to be cheap. My only suggestion is to look at some of the older cartridges that will do the same thing ballistically, before leaping.

Good Luck with your project.

Ray

You're actually much more helpful than someone saying build it because you might actually know if the cartridge has already been developed. I just figured perhaps my goals weren't explicitly stated enough...

I think more research needs to be done on the entire issue of powder buring. I know the military has done lots of research into this information and they seem to show that cartridges like the 220swift or old 6mm Lee have very efficient designs due to the powder to bore ratio.

That is another issue am I just trying to stuff too much powder down the 6mm bore? If so than I will wear out the barrel long before I see any improvements in velocity. I would like to model it all first mathmatically and then see if my theory holds up to empirical testing.

but that's for the help.