Just ordered a Rock Creek barrel

[sambo3006]

screech,
Good question. Believe me I would love to build one of those monsters. However, I have my first born on the way and am trying to fund this project completely by selling off stuff that I don't use anymore. Don't think I have enough old stuff to build a 408CT based round!

No modification of my bolt or receiver is needed for the RUM as opposed to a 338 Lapua based round. I even considered an improved version of the 300RUM, but when I considered the higher cost of the dies and the fireforming all to get maybe 100 fps more, the numbers just didn't add up for me.

One other factor is resale value if-Heaven forbid-I absolutely needed the money. The market for a left handed labor intensive wildcat round is probably pretty small.

All of these factors = 300RUM. I could always rechamber to a larger round later if I wanted to.

 

[James Jones]

I think that the 30-378 case is just about the max for the 30 cal bore , after that you will be brurning so much more powder and gaining very little velocity.
I think that a case built on the Chytac but shortened to hold around 95-100 grains would be great, little body taper and a 35 deg shoulder , I think that you would be basicaly be reinventing the 300 RUM velocity wise but in a shorter more effecient case and better brass

Hey Kirby , what are the ods of being able to shoot 180 and 200gr class bullet out of barrel rifled to shoot these looong bullets? I woulden't want to build anything that woulden't be able to use conventional bullet also

 

[Fiftydriver]

Eaglet,

Well, Richard and I pushed the envelope with the 224 Allen Magnum and his 107 gr ULD RBBTs. That is the only round, so far that has not provided what we want but new bullets are being built to remedy that as we speak!!!

I figured we needed to push the envelope with the 30 cal as well. My 300 Allen Xpress will top a 300 RUM or 300-338 Lapua and will come very close to matching the 30-378 with less powder simply because the dramatically stronger case will take more top end pressure with ease compared to the Norma made 30-378 Wby cases.

In my mind, an Allen Magnum has to offer more then anything else out there in its class. THis is the reason the 300 Allen Xpress was so named.

The 300 Allen Magnum will be a 338 Allen Mag necked down to 30 cal. I think it will be appropriately named!!

Kirby Allen(50)

 

[Fiftydriver]

Screech,

Already rolling my friend, stay tuned this spring and summer for some 290-300 gr 30 cal bullets going VERY fast.

Kirby Allen(50)

 

[Fiftydriver]

JDJones,

Thats not a very good attitude to take on a big 30 cal!!! /ubbthreads/images/graemlins/grin.gif

Overbore, come on now, I have been hearing this the entire time I have been playing with the Allen Magnums. The key to using these very large cases efficently is to use an extremely heavy bullet for caliber.

Take my 257 Allen Mag for instance, many would correctly say that with conventional bullets, 95 to 100 gr capacities are just to much for this bore diameter. That is true when dealing with bullets in the 85 to 120 gr range.

Drop in a 156 gr ULD RBBT and its a totally differnt story!!

I have three designs for the 300 Allen Magnum. All are the same basic design, only difference is length of the body. There are three lengths, 2.700" case length, 2.850" and full length 3.050" case length.

The shortest length would have a capacity about 15 grains more then a 30-378 Wby. I am going to start with the full length version first and see what happens.

Please realize that I do not see the 300 Allen Magnum practical for any bullet under 250 gr in 30 cal. Just like my 338 AM and my opinion there is no reason to shoot anything under 300 gr in that chambering.

Better yet in the 300 Allen Mag will be the new 265 gr ULD RBBT, 290 gr ULD RBBT and even the 300 gr ULD RBBT if Richard releases one.

If someone wants to shoot a 180 to 200 gr bullet then they might as well just order the Xpress or a RUM or 30-378 because it will be a waste of time with the big Allen Mag.

As far as the 180 and 200 gr pills go, they would perfectly at home in a 1-10 twist 300 Allen Xpress. TO that point, if you use a 180 gr or 200 gr Accubond, they will handle anything you can throw at them down to a 1-8 twist barrel.

Come on, don;t we need a 145 gr powder capacity 30 cal magnum!!! /ubbthreads/images/graemlins/grin.gif /ubbthreads/images/graemlins/grin.gif

Kirby Allen(50)

 

[coupalr]

JonA, Did you get a chance to let some of those 290's fly this weekend? I was talking to Richard today and I think I need a new rifle.

 

[Jon A]

Unfortunately no, some things came up this weekend. ****ed me off too, because the weather would have been great for shooting Sunday. Hopefully within the next few days.

 

[coupalr]

Jon, are shooting those without a brake on that thing?

 

[Jon A]

Yes.

 

[Chawlston]

Jon A,

What is the expected BC of the 290s?

James

 

[coupalr]

BC 1.0 or higher, so I have heard from a good source.

 

[Jon A]

I'll wait for testing to quote a hard number, but I fully expect it to be a significant step up from the 300 grain .338 SMK. It's got a 16% advantage in SD and a form that looks to be as "pointy" or even "pointier." We'll just have to see how they fly.... /ubbthreads/images/graemlins/laugh.gif I will guarantee that comparisons to any other current 30 Cal bullet will be laughable.

I should also mention I have some 265 RBBT's. BONDED CORE! Richard left the meplats slightly larger on these with a larger hollow point to ensure expansion at really low velocities. The BC won't be quite as high on these but I'm guessing they're going to give unbelievable terminal performance.

If that wasn't enough, Richard now has some shorter jackets to make down to about 250 grains which might work fine in a 1:10 twist.

Things are looking very good for big 30 Cals at the moment. FINALLY! /ubbthreads/images/graemlins/laugh.gif

Finally, we have the bullets available to get the most out of our rounds.

 

[jmden]

Fifty and JonA,

Keep us posted with these exciting developments! This is great news for the 30 cals! JonA, that pic you posted is pretty impressive...

 

[sambo3006]

John A,
What sort of velocity difference have you seen between the 265 ULD RBBT and the 290 ULD RBBT? I plan on trying both bullets in my 300RUM 30" when it gets put together. Probably will use the one that seems to group better from my barrel. Either way, the elk in a couple of basins in western CO are in some serious trouble next year!