The 6UM

[khuber84]

What do you like for min neck clearance hunting? That's part of where I screwed up on my one custom reamer order. Shouldn't have listened to the bench guys!

4-5 thou for cartridges, under 60gr, 5 though for case larger. I turned some Norma improved for 6thou clearance, and it works great. 5 is kinda the gold standard. Anything under 4 and it's tight getting a bullet into a fired case, and I don't like that. Tight necks are for the benchrest/F-class bois.

 

[BHenderson]

Does a 6 UM feed reliably out of any of the factory Tikka magazines?

 

[Ryan Avery]

Does a 6 UM feed reliably out of any of the factory Tikka magazines?

Yes, I use a LA Mag and the 6.5 PRC mag. No issues with either

 

[UpNorth89]

Has anyone had issues with a 7 twist yet?

 

[Sjacskson]

Any insight on when FF 40degree brass will ship???

 

[gtriple]

Can somebody please check my math on the below?
I've heard Ryan and Jake say that the 6UM kicks "like a 6.5CM". Both are with an 8lb rifle, which is my planned lightweight Tikka build. Using this website as the calculator: https://shooterscalculator.com/recoil-calculator.php

6UM: 108gr ELD-M, 66gr charge weight, 3200fps MV (18" barrel). This is about 18.1ft-lbs of recoil.

6.5CM: 143gr ELD-X, 46gr charge weight, 2850fps MV (24" barrel). About 16.1ft-lbs of recoil.

Edited for maximum charge weights. Looks much closer now.

 

[khuber84]

Standard 65cm loads are 41-42gr powder. But the 6um does have a bit more push to the shoulder than a 65cm.

 

[gtriple]

Standard 65cm loads are 41-42gr powder. But the 6um does have a bit more push to the shoulder than a 65cm.

Thank you, that gets it much closer.

 

[khuber84]

Thank you, that gets it much closer.

66gr N570 is pouring the coals with crack powder to the UM.

46gr rl26 is pouring the coals to the 65cm with crack powder. They're even closer in that comparison. Mv of a 140ish bullet with the 46gr rl26 charge would be 2850. This would be the most comparable apples to oranges data.

 

[Ryan Avery]

I just got back from Nilgai hunting in Texas. The 6UM went three for three with one-shot kills. Once again, the outfitter/guide was concerned about using a 6MM on Nilgai, especially the bull. He wants a 30cal with a 200g bullet doing 3000 FPS. But, like the PH in Africa, he had questions once they saw this bullet-chambering combo in action. I guess it had enough wallop...

My son was first up. 150-yard shot through the lungs, and the cow went 50 yards.



My cow was 220 yards through the lungs. She went about 40 yards.



lungs

Entry



Exit



Tanya's shot was about 140 yards. She made a great shot; the bull went 40 yards.




Entry



The 6UM is a BEAST!

 

[wysongdog]

Looks great. My brass just showed up last week now waiting on the gun lol

 

[Ryan Avery]

Can somebody please check my math on the below?
I've heard Ryan and Jake say that the 6UM kicks "like a 6.5CM". Both are with an 8lb rifle, which is my planned lightweight Tikka build. Using this website as the calculator: https://shooterscalculator.com/recoil-calculator.php

6UM: 108gr ELD-M, 66gr charge weight, 3200fps MV (18" barrel). This is about 18.1ft-lbs of recoil.

6.5CM: 143gr ELD-X, 46gr charge weight, 2850fps MV (24" barrel). About 16.1ft-lbs of recoil.

Edited for maximum charge weights. Looks much closer now.

The math is probably correct.

When shooting my 6.5CM and the 6UM, I spot hits equally well. However, when I move up to a 6.5 PRC, I really have to pay attention to see my hits.


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