168 SMK vs 168 STMK

[Honchom3]

I know the topic has been beaten to death.

I was out yesterday on a friend's farm with my 308 shooting at a mild 484 yards.
Shot 4 rounds of the 168smk
Loaded with 48.6g of CFE223 with fed 210m primers.
Adjusted the scope probably for distance. Hit a 10inch gong 4 out of 4. Dope on the scope us
2.6 mils up and .2 mils left.

Same gun same target but with 168 STMK with the same powder charge and primers.
Scope dope
2.3 mils up. (Happy with that)
.5 mils left???

I found it odd that the tipped match king were shooting that much farther right.

Has anybody experienced this before?

Thanks
Mike

 

[clcustom1911]

Different meplat shape, length, etc have different effects during flight due to BC differences, gyroscopic stability, and all that mumbo-jumbo.

What was the wind like?

I used to experiment with all manner of different bullets and noticed a whole bunch of things from bullet to bullet.

 

[Honchom3]

Different meplat shape, length, etc have different effects during flight due to BC differences, gyroscopic stability, and all that mumbo-jumbo.

What was the wind like?

I used to experiment with all manner of different bullets and noticed a whole bunch of things from bullet to bullet.

Wind was mild at best a few gusts but others wise 2 maybe 3 mph winds mostly blowing at me when is was blowing. Shooting when I noticed a lull in the wind.

Curious as to if this will be a constant variable with the tipped match king.
Deciding on what I want to take to my first PRS match in NY in April

 

[OLD308]

Agree. Same brass, primer, powder charge, but different bullet will shift left to right zero. Don’t worry about a thing.
I would like to hear your experience on the MK vs TMK.
Personally, they were not worth the price difference to me. So I went back to the 155 MK.

 

[clcustom1911]

Pick one bullet. That eliminates the variable of switching from one bullet to another.

 

[Honchom3]

Agree. Same brass, primer, powder charge, but different bullet will shift left to right zero. Don’t worry about a thing.
I would like to hear your experience on the MK vs TMK.
Personally, they were not worth the price difference to me. So I went back to the 155 MK.

Personally I like the less drop that the STMK has over the non tipped.
I am a little disappointed with the drift. I know its different bullet.
I think that would be more of a challenge to get figured out in a short amount of time that I have.
I am not fancy or have wind meters. But I do use the Hornady app on the phone and it has proven itself with the 168Mk and on my 6.5 creedmoor.
I just have no way of communicating the drift difference unless I make range cards for certain distances.

 

[Honchom3]

Pick one bullet. That eliminates the variable of switching from one bullet to another.

I agree, I will be sticking with the non tipped match kings for now.

 

[6brshooter]

Was the 168 tmk zeroed at 100, or are the smk and tmk same poi/poa at 100?

 

[Steel head]

Was the 168 tmk zeroed at 100, or are the smk and tmk same poi/poa at 100?

This.

 

[Honchom3]

Was the 168 tmk zeroed at 100, or are the smk and tmk same poi/poa at 100?

I have zeroed them both at 100y
That particular day I did not shot the rifle at 100y. Just 484, dialed the scope for the specific drop for the smk.
I did anticipate the less drop from the better BC STMK. I did not expect the 3mil difference in windage.
I was indeed holding same point of aim

 

[spife7980]

That wasn’t exactly a clear answer. You zeroed them both... did they have the same zero then?

I’d zero one, shoot at distance. Then I would zero the second, shoot at distance.
If they don’t share the same 100 yard zero exactly then of course they won’t share it further out.

 

[Honchom3]

That wasn’t exactly a clear answer. You zeroed them both... did they have the same zero then?

I’d zero one, shoot at distance. Then I would zero the second, shoot at distance.
If they don’t share the same 100 yard zero exactly then of course they won’t share it further out.

I apologize for that.
The rifle was zeroed for both at separate times.
I dont recall them being that different at a 100 but again I can't recall.
The current zero is for the 168mk
I guess I assumed incorrectly by think the better BC bullet would have better holds left and right.
I can zero the TMK at 100y and shoot back at 484y and then compare scope adjustments. This would provide the best comparison?

Thanks Mike.

 

[spife7980]

However you do it, just account for the natural offset between the two bullets.

 

[Honchom3]

However you do it, just account for the natural offset between the two bullets.

Thank you for the help.
I will try and get out soon to test.
The match is not canceled just yet.
And not much time yo test and reload 100 rounds. The weather in PA sucks right now.

Also I am still learning. What do you mean by offset?
I know the bullets are two different shapes. The are seated to just about the same length do to magazine restrictions.

Thanks Mike

 

[Steel head]

Thank you for the help.
I will try and get out soon to test.
The match is not canceled just yet.
And not much time yo test and reload 100 rounds. The weather in PA sucks right now.

Also I am still learning. What do you mean by offset?
I know the bullets are two different shapes. The are seated to just about the same length do to magazine restrictions.

Thanks Mike

You can zero for one then shoot the other and measure any difference from POA and enter that difference into a ballistic solver.
The difference in POI from POA is the offset.
Then you could shoot both in similar conditions and get a real comparison.

 

[6brshooter]

I'm gonna be playing with some 69tmk, currently run 69smk in a mk12 mod0 upper. OP, are your 168 tmk and smk the same powder charge/same accuracy? Or did you have to tweak the load for each bullet? I was hoping it would be a straight up bullet swap. Sorry for thread hijack.

 

[Honchom3]

You can zero for one then shoot the other and measure any difference from POA and enter that difference into a ballistic solver.
The difference in POI from POA is the offset.
Then you could shoot both in similar conditions and get a real comparison.

Awesome thank you.
So basically I can do that now since I shot both same day back to back.

Do you have any recommendations on a ballistic solver?

 

[Honchom3]

I'm gonna be playing with some 69tmk, currently run 69smk in a mk12 mod0 upper. OP, are your 168 tmk and smk the same powder charge/same accuracy? Or did you have to tweak the load for each bullet? I was hoping it would be a straight up bullet swap. Sorry for thread hijack.

It's all good.
Basically I did a bullet swap.
I hope this helps. It's at least a good starting point.

 

[Steel head]

Awesome thank you.
So basically I can do that now since I shot both same day back to back.

Do you have any recommendations on a ballistic solver?

I use Ballistic AE on my phone but it’s not as popular now.
I’d research in the ballistics section.
lots of great information there.

Ballistic Calculator Discussion

All things ballistic calculators, from applied ballistics to TRASOL.

www.snipershide.com

Here’s the area in my app where you enter in any offsets.

 

[Honchom3]

I use Ballistic AE on my phone but it’s not as popular now.
I’d research in the ballistics section.
lots of great information there.

Ballistic Calculator Discussion

All things ballistic calculators, from applied ballistics to TRASOL.

www.snipershide.com

Here’s the area in my app where you enter in any offsets.
View attachment 7280271

Thank you for all the info.
I am downloading it now.