6UM alternative

[BRTreedogs]

So as a guy that doesn’t chase speed I’m definitely not in tune with case capacity and all that.

But I’ve always heard the 6.5-06 is a dream to load for easy cartridge.

What about a 6-06?

Is there such a thing? What would it do?

06 or well 270 win brass is a dime a dozen and it should feed etc easy peasy.

Maybe even Ai or plus P?

 

[6mm Remington]

So as a guy that doesn’t chase speed I’m definitely not in tune with case capacity and all that.

But I’ve always heard the 6.5-06 is a dream to load for easy cartridge.

What about a 6-06?

Is there such a thing? What would it do?

06 or well 270 win brass is a dime a dozen and it should feed etc easy peasy.

Maybe even Ai or plus P?

Or neck down 25-06 brass which would be even simpler to get it sized properly. I've always thought about building a a 6mm-06. It would be a speed demon. I'm awful partial to the 6mm Remington and it delivers the goods as far as accuracy and speed.

 

[BRTreedogs]

Or neck down 25-06 brass which would be even simpler to get it sized properly. I've always thought about building a a 6mm-06. It would be a speed demon. I'm awful partial to the 6mm Remington and it delivers the goods as far as accuracy and speed.

I have a buddy with a 6.5-06 and he says it was just such any easy button.

Did barrel break in and it just hammers easy peasy.

Personally I loathe reloading so I want factory ammo whenever possible.

But if I had a standard bolt long action laying around I couldn’t resist the 6.5/06 I don’t think.

 

[The Guide]

Any can be made into a 6mm but probably not going to be as easy as the 6UM 30 deg (6 PRC) when their brass does arrive.

The 6UM 30⁰ is a 6 SAUM not PRC.

Jay

 

[GoatPackr]

The 6UM 30⁰ is a 6 SAUM not PRC.

Jay

Your right.
Brain fart..
I'll fix that

 

[RockCreekGuy]

So as a guy that doesn’t chase speed I’m definitely not in tune with case capacity and all that.

But I’ve always heard the 6.5-06 is a dream to load for easy cartridge.

What about a 6-06?

Is there such a thing? What would it do?

06 or well 270 win brass is a dime a dozen and it should feed etc easy peasy.

Maybe even Ai or plus P?

The -06 has about the same case capacity as the 6.5prc. I don't care for the shoulder angle and if we're back to improving we're back to 6UM or Primal's 6PRCai. I don't own an action suited for it either.

 

[Axlrod]

I was wanting a new 6mm about a year ago. After some research, I went with the 6-7PRC (6ROKUM). I had UM build it. It's on a Tikka action in a Rokstok, with UM bottom metal/mags. They already had a reamer. Brass was available as were Hornady 7PRC bushing dies. I picked up the rifle in July, and I am close to 500 rounds through it. The neck clearance was tight on fired Adg brass, so I turned the necks. I am shooting 115 Dtacs at 3292 fps w/N570. I am very happy with it.

 

[GoatPackr]

I was wanting a new 6mm about a year ago. After some research, I went with the 6-7PRC (6ROKUM). I had UM build it. It's on a Tikka action in a Rokstok, with UM bottom metal/mags. They already had a reamer. Brass was available as were Hornady 7PRC bushing dies. I picked up the rifle in July, and I am close to 500 rounds through it. The neck clearance was tight on fired Adg brass, so I turned the necks. I am shooting 115 Dtacs at 3292 fps w/N570. I am very happy with it.

What bushing are you running?
How much did you end up turning the necks.
I'm shooting a Tikka 6 ROKUM as well.

 

[Axlrod]

What bushing are you running?
How much did you end up turning the necks.
I'm shooting a Tikka 6 ROKUM as well.

New brass I did in 3 steps .302/.288/.273 Then I turned it to .014" thick with a Hornady neck turning lathe. Starting at the second loading on the brass I am using a .267 bushing. This yields .004" neck tension.

 

[B23]

With ADG making good brass for them a 6-6.8 Western has to be really close to being a ballistic twin to the 6UM except a 6-6.8 Western would be a straight neck down with no fireforming.

 

[GoatPackr]

With ADG making good brass for them a 6-6.8 Western has to be really close to being a ballistic twin to the 6UM except a 6-6.8 Western would be a straight neck down with no fireforming.

I'm not familiar with that case. How's it compared to a 7 PRC case? Shorter?

 

[The Guide]

I'm not familiar with that case. How's it compared to a 7 PRC case? Shorter?

This member is necking it down to 257 and has some case info.

Jay

The .257 Marksman (25 western)

As some of you guys know I've been putting together a wildcat, well it's here. Purpose is a cartridge that fits good in a SA magnum launching the 130 class .257 projectiles at 3000 fps plus with a 20 inch or less suppressed rifle. Barrel life be damned 😁 It's not anything too crazy, simply a...

rokslide.com

 

[BBob]

The -06 has about the same case capacity as the 6.5prc. I don't care for the shoulder angle and if we're back to improving we're back to 6UM or Primal's 6PRCai. I don't own an action suited for it either.

6 Gibbs would be something. Takes care of the 06 shoulder angle

 

[B23]

I'm not familiar with that case. How's it compared to a 7 PRC case? Shorter?

Much shorter then the 7 PRC case. The 6.8 Western is basically a "improved" RSAUM with 35° shoulder. It has about the same case capacity as the 6 UM which is right around 75gr H2O +/- but like I mentioned earlier it would be a straight neck down with no fireforming step.

With ADG making 6.8 Western brass I can see one of these as the parent case for .243/6mm, .257, or 6.5 versions becoming a popular item.

 

[khuber84]

The 6UM 30⁰ is a 6 SAUM not PRC.

Jay

Actually it's not. 6um 30° brass doesn't chamber in 6saum chambers cut to Saum headspace. The UM 30° is a deeper chamber and the shoulder is longer on the brass. So 6UM 30 is it's own thing unfortunately. Would be nice if they did cross over and 6saum was that simple, buy brass, load and shoot.

 

[AZ_Hunter]

Much shorter then the 7 PRC case. The 6.8 Western is basically a "improved" RSAUM with 35° shoulder. It has about the same case capacity as the 6 UM which is right around 75gr H2O +/- but like I mentioned earlier it would be a straight neck down with no fireforming step.

With ADG making 6.8 Western brass I can see one of these as the parent case for .243/6mm, .257, or 6.5 versions becoming a popular item.

I think this is the easy answer and will spawn some good wildcats.

 

[RockCreekGuy]

I was wanting a new 6mm about a year ago. After some research, I went with the 6-7PRC (6ROKUM). I had UM build it. It's on a Tikka action in a Rokstok, with UM bottom metal/mags. They already had a reamer. Brass was available as were Hornady 7PRC bushing dies. I picked up the rifle in July, and I am close to 500 rounds through it. The neck clearance was tight on fired Adg brass, so I turned the necks. I am shooting 115 Dtacs at 3212 fps w/N570. I am very happy with it.

I've followed a few of your posts. Access to the right reamer certainly makes the process more complex than just click and buy. It's beginning to feel like I'm going to have to buy a reamer. You must be running a shorter barrel as well. I'd think your velocity would be higher on N570, though perhaps you're not stepping on it either. I'd be interested to your your charge weight vs where you hit pressure signs.

 

[WKR]

Much shorter then the 7 PRC case. The 6.8 Western is basically a "improved" RSAUM with 35° shoulder. It has about the same case capacity as the 6 UM which is right around 75gr H2O +/- but like I mentioned earlier it would be a straight neck down with no fireforming step.

With ADG making 6.8 Western brass I can see one of these as the parent case for .243/6mm, .257, or 6.5 versions becoming a popular item.

The 257 has already happened. And it's a good one.
I'm considering a 6mm version but need to focus on one thing at a time. The 6mm would be FAST

 

[RockCreekGuy]

With ADG making good brass for them a 6-6.8 Western has to be really close to being a ballistic twin to the 6UM except a 6-6.8 Western would be a straight neck down with no fireforming.

I agree and when I looked at all of the Lapua and ADG brass I certainly noticed the 6.8 being right there on capacity with the SAUM and has a 35⁰ shoulder. I like it. In case any don't know, ADG has case capacity published for each of their cases. Numerically, it's a fine suggestion as a parent case for a project like this. I just don't want anything to do do with 6.8 brass or dies.

I'm gaining a lot of respect for the dollars you're all spending on reamers, brass, dies, barrels and smithing every time you want to try something new. You can buy a basic new stainless Tikka for the price of the barrel and smithing alone, sometimes less.

 

[The Guide]

Actually it's not. 6um 30° brass doesn't chamber in 6saum chambers cut to Saum headspace. The UM 30° is a deeper chamber and the shoulder is longer on the brass. So 6UM 30 is it's own thing unfortunately. Would be nice if they did cross over and 6saum was that simple, buy brass, load and shoot.

I just meant that the parent case was SAUM based not PRC based. Since the 6UM brass is made for the 40⁰ case but unfireformed, it makes sense that it may not work as they had it necked down and formed to their specified dimensions.

Jay