The 6UM

[JQuaglino]

I'm interested in your dtac experience.
I've been using 109 eld-m and they haven't let me down but those dtacs look mean

If someone has built one I would love to chat with them. I haven’t found one yet searching the internet.
I have found lots of info on the 6mm SAUM but not an improved version.


Sent from my iPhone using Tapatalk Pro

What makes it improved? I’m assuming bullet angle and if so what is the difference?

 

[wind gypsy]

What makes it improved? I’m assuming bullet angle and if so what is the difference?

Generally "improved" means fireforming the brass to have more capacity than parent cartridge via 1 or more of the following:

• Making case shoulder angle steeper
• Blowing the shoulder further forward
• Reducing the case body taper

More capacity = more powder = mo faster

Less body taper, steeper shoulders = Less case stretch

There are improved variants that push the shoulder back some too which makes the neck longer.

 

[JQuaglino]

Generally "improved" means fireforming the brass to have more capacity than parent cartridge via 1 or more of the following:

• Making case shoulder angle steeper
• Blowing the shoulder further forward
• Reducing the case body taper

More capacity = more powder = mo faster

Less body taper, steeper shoulders = Less case stretch

There are improved variants that push the shoulder back some too which makes the neck longer.

Thanks. I was hoping to get the cartridge differences between the 6 um and a 6 SAUM.

 

[Harvey_NW]

Thanks. I was hoping to get the cartridge differences between the 6 um and a 6 SAUM.

Pg 1 post #19 has a fireformed pic for comparison.

 

[JQuaglino]

Pg 1 post #19 has a fireformed pic for comparison.

Thanks I missed that somehow.

 

[Ryan Avery]

She will fit in a short action.


Sent from my iPhone using Tapatalk Pro

 

[mullmann]

It would be nice if UM would offer brass that is fire formed like defensive edge does for the terminator cartridges.

 

[Ryan Avery]

It would be nice if UM would offer brass that is fire formed like defensive edge does for the terminator cartridges.

Once we get all the details lined out there will be FF brass for sale on UMs website.


Sent from my iPhone using Tapatalk Pro

 

[JQuaglino]

Do you think the right bullet for it exist currently? That’s a screamer with some serious propulsion behind it. Just thinking about. Seems a big gap between the a 105 to 115 bullet to the 147s and 156s that 6.5 saum and prc shoots.

 

[Ryan Avery]

Do you think the right bullet for it exist currently? That’s a screamer with some serious propulsion behind it. Just thinking about. Seems a big gap between the a 105 to 115 bullet to the 147s and 156s that 6.5 saum and prc shoots.

The right 120-grain bullet would be nice but more bullet more recoil.

 

[JQuaglino]

The right 120-grain bullet would be nice but more bullet more recoil.

Very true. Would a 120 class bullet cut the wind better or worse or would it be a zero sun game because it’s a higher weight longer bullet yet slower speed. Compared to 105 to 115 bullet respectively?

 

[amassi]

Very true. Would a 120 class bullet cut the wind better or worse or would it be a zero sun game because it’s a higher weight longer bullet yet slower speed. Compared to 105 to 115 bullet respectively?

Not a lot of fat to trim with the 108-118 class 6mm, at 5,000 ft they're 9 mph wind # and drop less than 5 mils at 1000 at the velocity Ryan's getting with the 6um.

 

[Formidilosus]

Well….

 

[Ryan Avery]

First Blood!

640 yards

Sent from my iPhone using Tapatalk Pro

 

[JQuaglino]

Finally got some rounds loaded. Should have some speeds next weeks. I started with VV565 but I don’t think that will be “the powder”

The water capacity is 75g

6UM next to a 6CM

Sent from my iPhone using Tapatalk Pro

What was the overall length on the bullet for the 6UM?

 

[Ryan Avery]

Exit


Sent from my iPhone using Tapatalk Pro

 

[justin davis]

Exit


Sent from my iPhone using Tapatalk Pro

First Blood!

640 yards

Sent from my iPhone using Tapatalk Pro

Badass

 

[DoveBlaster]

Looks like it works!

 

[WMWILLIAMS]

Very impressive think I need


Sent from my iPhone using Tapatalk

 

[PathFinder]

Well….

View attachment 499987

Would you consider this to be desirable performance, acceptable, or more of a fluke outcome? You've seen terminal performance from a decent number of these DTACs now, is this common or do they usually fragment?

Sent from my Pixel 6 using Tapatalk