6 UM Reloading Thread

Basically just jam the bullets .010-.020 and use a mild load of 7828 or H1000 (55-59 gr). Those Game Kings should work fine.
N570 is the undisputed speed king for the 6 UM. It will give you ~100 fps over anything else. Pretty much every 6 UM barrel seems to shoot 66 gr N570 with a coated 115 NR DTAC at .060" off really well.
Thanks for the info. I'm curious the purpose of jamming into the lands as opposed to increasing the powder charge a little. Is it for centering the bullet better or just for pressure/forming?
 
Thanks for the info. I'm curious the purpose of jamming into the lands as opposed to increasing the powder charge a little. Is it for centering the bullet better or just for pressure/forming?
I think you form a better shoulder by jamming, hence the reduced loads
 
Thanks for the info. I'm curious the purpose of jamming into the lands as opposed to increasing the powder charge a little. Is it for centering the bullet better or just for pressure/forming?
It's mostly to account for excess headspace. If there's too much headspace, the case can stretch too much near the head and cause a case head separation. Or it can result in a light primer strike. Ideally, an improved chamber will be cut so that the neck of the unformed case jams up against the neck in the chamber. But that's not always how they are, so jamming the bullet a bit ensures that any excess headspace doesn't cause issues.

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Ive been fire forming my 6UM 40. Got the DTACs today! I'll shoot real loads soon.

I'm curious how many rounds cases are lasting with the seemingly standard load of 66gr N570?
 
I'm using the .271 neck bushing for my 6UM. I'm getting about .0015 neck tension. Is this enough for hunting or should I drop down one bushing size?
 
If I'm using a 115 dtac nose ring in a 6cm should I put .292 g7 bc in my strelok?

Yes


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Looking at bullet options, I see a lot of folks going with the 115 dtac, I’m also looking at the Berger 108 elite hunter with an advertised G7 bc of 0.287. Thinking I’d likely get another 70-80 fps out of the 108 Berger, which I would think overcomes the small difference in bc (0.292 vs 0.287) between the two.

Looking for opinions, are there any other compelling reasons to go with the 115 dtac’s over the 108 eh’s?
 
Looking at bullet options, I see a lot of folks going with the 115 dtac, I’m also looking at the Berger 108 elite hunter with an advertised G7 bc of 0.287. Thinking I’d likely get another 70-80 fps out of the 108 Berger, which I would think overcomes the small difference in bc (0.292 vs 0.287) between the two.

Looking for opinions, are there any other compelling reasons to go with the 115 dtac’s over the 108 eh’s?
Ive tried the 109 bergers in mine and with the same load I use on my 115s, the 109s are slower. Even after I hbn coated them. In order for my rifle to reach the same speed I have to add another gr of powder.
 
First 10 shot groups with dtac.
Tikka, 20" ace, 8 twist
66gr N570, .060 off lands
38 rounds through barrel before this.

3260 fps, spread 46.5, sd 15.4

Not sure what happened with first shot but the rest seems good. I was super stoked going into shot 9. Ha.

Thoughts, questions or suggestions?1000002790.jpg
 
I'm using 6.5 SAUM, ADG brass. Has anyone neck turned to see if there is any difference in performance?

I'm just wondering if I should spend the time or not?
 
First 10 shot groups with dtac.
Tikka, 20" ace, 8 twist
66gr N570, .060 off lands
38 rounds through barrel before this.

3260 fps, spread 46.5, sd 15.4

Not sure what happened with first shot but the rest seems good. I was super stoked going into shot 9. Ha.

Thoughts, questions or suggestions?View attachment 888827
Roll with it. A small increase in precision doesn't mean anything in the field. With the 6UM in particular, the cost isn't worth the warm fuzzies of shooting a small group on paper. I tinkered with mine for ~150 rounds and found that it didn't care one bit what changed, it's a 1.5 MOA gun. That was a lot of barrel life just to satisfy curiosity.
My conclusion for any 6UM barrel is to feed it exactly that load, and if it shoots decent and produces roughly that velocity to stop tinkering and just hunt with it.
 
The UM using magnum or just standard primers? Thought I saw a 210 mentioned. I've got a lot of 210m just only a few win mag primers.


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Roll with it. A small increase in precision doesn't mean anything in the field. With the 6UM in particular, the cost isn't worth the warm fuzzies of shooting a small group on paper. I tinkered with mine for ~150 rounds and found that it didn't care one bit what changed, it's a 1.5 MOA gun. That was a lot of barrel life just to satisfy curiosity.
My conclusion for any 6UM barrel is to feed it exactly that load, and if it shoots decent and produces roughly that velocity to stop tinkering and just hunt with it.
There you go being logical and practical and killing my tinkeritus to save me time and money
 
The UM using magnum or just standard primers? Thought I saw a 210 mentioned. I've got a lot of 210m just only a few win mag primers.


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I use magnum primers in most loads. Mostly because I have a lot of them. I definitely would in the 6UM. I even use them in 6CM.
 
Thanks for the info. I'm curious the purpose of jamming into the lands as opposed to increasing the powder charge a little. Is it for centering the bullet better or just for pressure/forming?

Jamming the bullets keeps the case head pressed against the boltface when the firing pin hits the primer which helps get more consistent and complete case forming and reduces case stretch (expands more from shoulders out than from case web forward).
 
My dies will be here tomorrow!

Read through most of these posts. I remember talking to Ryan the other day about using h1000 to fire form. Can't remember the charge weight... think it was 58 grains.
Also no cheap 6 mike mike pills in town. Just eldms for heavier stuff over 100 grains. So I'll probably be stuck buying those and using with some h1000 since there's no 7828 in town.
Also have retumbo. Some R23 too I think.
 
Received an email from Powder Valley today noting VihtaVuori prices are to increase in August. Thought I’d mention it here if anyone is contemplating stocking up on N570. IMG_0502.jpeg
 
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