30 Cal 195gr TMK on game

pyrotechnic

Lil-Rokslider
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Nov 7, 2019
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Hi guys, I've been reading the forum for quite a while and have picked up quite a bit. Finally decided to register.

Has anyone used the Sierra TMK on deer and elk? Particularly the 195gr .30 Cal. I'll be launching them out of a .30-06 so muzzle velocity would be 2700 or so.

Thanks.


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Totoro

WKR
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Well I have used them in a 300WSM and on flesh, its pretty traumatic. Aim for the crease and let it fly.

I havent tested on deer sized shoulder hits but on songdogs its no suprise.

Placement is paramount.

As other alternative if you plan on shoulder hits, ELDX or TTSX.
 
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pyrotechnic

Lil-Rokslider
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Nov 7, 2019
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Well I have used them in a 300WSM and on flesh, its pretty traumatic. Aim for the crease and let it fly.

I havent tested on deer sized shoulder hits but on songdogs its no suprise.

Placement is paramount.

As other alternative if you plan on shoulder hits, ELDX or TTSX.
Not planning on shoulder hits, but figured I'd ask.
Thanks.

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keepriding

Lil-Rokslider
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Apr 20, 2019
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I have been testing these the last few months after Sierra sent me a few hundred to do so. Been too cold for long range testing as a final analysis, but here was my very preliminary powder test velocities. The first shot was from a clean cold bore and was also used to get my scope aligned. You probably can see that shot high just in the photo frame. After a few clicks adjustment, I shot low charge weight to high, then high to low with magnetospeed attached. I settled on 2667fps for further testing.
 
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pyrotechnic

Lil-Rokslider
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Nov 7, 2019
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The 195 TMk worked well on my mule deer a couple days ago. I did end up smashing through his shoulder. 200 yd shot. He fell over and kicked a little bit. No exit.

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woods89

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Not a 30 cal, but I found the 130 gr 6.5 version to be a devastating killer in my 6.5 Creedmoor. 2 deer this year, impacts 2700ish. They were a little messy but killed quick!
 

ericwh

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Sierra's site recommends 1:10 twist for the 195TMK. Any word on if these would stabilize in a 1:11 Tikka 300wsm? Most of my hunting would be >5k' elevation but load development and practice is at a lowly 800'

Trying to decide if I would need to re-barrel or if I could make due with the factory barrel.

EDIT: If I need to re-barrel I could buy any magnum tikka, if the 300wsm will stabilize a .61 B.C. Tipped Bullet I will wait until I can find a 300wsm and just use the factory barrel - perhaps with throat and magazine modifications if necessary.
 
Last edited:
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Nov 12, 2016
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Sierra's site recommends 1:10 twist for the 195TMK. Any word on if these would stabilize in a 1:11 Tikka 300wsm? Most of my hunting would be >5k' elevation but load development and practice is at a lowly 800'

Trying to decide if I would need to re-barrel or if I could make due with the factory barrel.

EDIT: If I need to re-barrel I could buy any magnum tikka, if the 300wsm will stabilize a .61 B.C. Tipped Bullet I will wait until I can find a 300wsm and just use the factory barrel - perhaps with throat and magazine modifications if necessary.
If someone will post the bullet length, you can run the numbers on Berger's website. I suspect you will have marginal stability at 800' and be fully stabile at 5000'.

You can always give them a try since you live in the worse condition. If they shoot at 800' they will be fine at 5000'.

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ericwh

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I had it in my mind the Berger tool wasn't totally accurate for tipped bullets?
 

ericwh

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Found bullet length on jbmballistics.com: 1.475 long. Plastic tip is .200

At 2800fps and 800' elev,
Using 1.475 it says SG = 1.41/Marginally Stable
If I subtract the .2 of the tip and use 1.275 for length I get SG=2.15/Stable
Split the difference and use 1.375 I get SG=1.73/stable
 
Joined
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Messages
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Found bullet length on jbmballistics.com: 1.475 long. Plastic tip is .200

At 2800fps and 800' elev,
Using 1.475 it says SG = 1.41/Marginally Stable
If I subtract the .2 of the tip and use 1.275 for length I get SG=2.15/Stable
Split the difference and use 1.375 I get SG=1.73/stable
I had it in my mind the Berger tool wasn't totally accurate for tipped bullets?

The Berger tool uses the Miller Stability Formula which is not quite perfect for tipped bullets as you point out.
Subtracting the tip will get you closer to the correct answer than leaving it on, but it is still not correct.

Unfortunately, the Stability Formula that is used is too simplistic to handle this situation. The copper & lead used for the jacket and core respectively are similar enough in density to assume a homogenous material. The plastic tip is not. Using the MSF to estimate the SG on a plastic tipped bullet will underestimate the SG. The best method currently is to subtract the tip length from the total length of the bullet.

A thought experiment about the physics:

Bullet A, no tip, length 1.5"
Bullet B, 0.2" tip, length 1.5"

If you input 1.5" for bullet A, it should be a good approximation.

If you input 1.5" for bullet B, it in essence moves the center of gravity forward to W, and the center of pressure forward by X, but W > X, the distance between the CG and CP is GREATER than in reality.

If you input 1.3" for bullet B, the center of gravity moves back by Y, and center of pressure moves back by Z,
but Y < Z, the distance between the CG and CP is LESS than in reality.

I think the last scenario should be MORE accurate because I believe that Z - Y < W - X.
 

Formidilosus

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Oct 22, 2014
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8,225
Sierra's site recommends 1:10 twist for the 195TMK. Any word on if these would stabilize in a 1:11 Tikka 300wsm? Most of my hunting would be >5k' elevation but load development and practice is at a lowly 800'

Trying to decide if I would need to re-barrel or if I could make due with the factory barrel.

It will stabilize just fine.
 
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