Savage Model 10 308. Sighted with 175 Fed Gold Match at 200, light bullets way high

[The22Man]

Factory rifle, no mods, 1 in 10" twist the plain LE model, 20" bbl
I understand the 175 is heavier and physics apply so let's get past that in an debate.
I will understand if "physics" is the answer.
I just did not expect such a height difference of 8 1/2 and 9" with some ammo.
Any of you had similiar?

at 200 yards -
150Gr Hornady Light Mag 4" high (Update: and 4+" right)
150Gr Hornady Superperformance SST 10 1/2" high and 4" right (updated, I put the 100 yard earlier)
155Gr Hornady TAP FPD 3 1/2" high

150GR Remington UMC MC 8 1/2" high

147Gr NATO 'surplus' 6" high
149Gr NATO 'surplus' 4 3/4" high

168Gr Federal Gold Match (White box) 2" high
168Gr Federal Gold Match (red / maroon / brown box) 1 1/4" high
168Gr Hornady TAP FPD 2" high
168Gr Winchester Ballistic Silvertip 9" high and way right

 

[chevytruck_83]

Im sure if you ran them all through a chronograph you would see the impacts relate directly with the velocity.

 

[Dshooter]

^^^^ this. Velocity increase in lighter bullets

 

[sib1948]

When I got and RWS Custom 308 2 years ago, the guy I bought it from had been using FGMM 168gr SMK. When I first took it out and shot at 100 yards with FGMM 175gr SMKs the horizontal was perfect, but 6 inches low. Sounds exactly like what you have been seeing! I would pick a bullet weight and stick with it. The 168gr SMK are good out to about 700 yards. If you want to go to 1000 yards, you'll need a minimum of 175gr or preferably 185gr.

 

[The22Man]

My buddy with the crono is at the CMP games for a few weeks.

My big surprise was -
150Gr Hornady Superperformance SST 10 1/2" high
and
168Gr Winchester Ballistic Silvertip 9" high - Though in all calibers (ok only 270 and 223) I have had issues with the Winchester Ballistic Silvertip

Most of the others were within reason for me.

I plan on sticking with the 175 FGM for now.

Thanks for the input.

 

[MoBoost]

Im sure if you ran them all through a chronograph you would see the impacts relate directly with the velocity.

@ 200 yards velocity (well, the small difference there is between the full power ammo) has very little vertical impact - barrel harmonics does; some rifles are more sensitive then other.

 

[chevytruck_83]

The superformance hornady loads claim to be the fastest for their weight, right? This matches his data. Harmonics definitely effect poi. Id like to see him run them through a chrono and see if the impact matches.

 

[The22Man]

It will be a few weeks before I have access to the chrono. So long as I don't forget, I will post the info here.
Until then, thanks a million for your input.

 

[chevytruck_83]

According to mfg data the superformance 150 are 3000fps and the 175 smk is 2600 fps. Thats a huge difference. With a gun zeroed for the 175 at 100. The 150 will be high at 100 and also 200. If I can find the superformance sst 150 ill try them and the federal gold 175 in my sako trg and I bet results are very similar.

 

[fdkay]

So are you asking a question here?
Yes, both velocity and barrel harmonics apply.
Your numbers for the FGMM 168 seem to be just about perfect.
Stretch all those rounds out to 7-800 yards and you'll see that they are likely shooting lower than the 175 match load. (possible exception is the 155 SST)