Loading 168gr. Berger VLD's in the 7mm Ultra Mag

[Dthunter]

Hi guys!

My 7mm ultra has always been finiky to reload for.
I cannot use the starting grain charges for any powders I have seen listed.
AA8700,H869,H870,Retumbo,H50BMG,H1000,RL25,IMR7828,etc.
They are ALL over pressured and the velocities are stupid fast!
After dropping 4-5grains below starting grain levels, things started to shape up.


Took the 7mm Ultra out last night.
All loads are with168 Berger VLD'S (Hunting)
The loading densities averaged about 85%ish or more.


90 grains of H870, Ave Vel: 3292fps, E.S. 22.36fps, S.D. 11.70fps. Group size: 0.679" (4shots).

90grains of H869, Ave Vel: 3279fps, E.S. 8.00fps, S.D. 3.60fps, Groups size: 0.426" (4 shots).

90 grains of H50BMG. Ave Vel: 3335fps, E.S. 73.11fps, S.D. 32.54fps, Group size: 0.936" (4 shots).

I am very pleased with the performance! Some serious velocity for the 168's!
They should hit HARD!

I look forward to trying these loads out to 1000+ yards!
I dont plan to shoot this rifle much, but it will be nice to have it calibrated out that far.

I may try the 180Gr. Berger VLD as well. hopefully it will shoot as well.

Hope you guys enjoyed the test results.

Take care,straight shootin, and keep it fun!

 

[bobnob]

Well I dont have that chambering but something looks amiss. If I read it right you are getting 200fps over max speeds with 10g under max loads.

That generally doesnt happen.

What does the brass, primer etc look like? Any other signs something is odd?

Not telling you what to do, just seems real weird.

 

[Dthunter]

Bobnob:

Yes it seems weird alright!
I am getting pressure somewhere. I
May try turning my case necks to see if it helps.
My case has about .004"-.006" of expansion room.
Pretty tight i think.
After firing the cases two/three times, I start to have case extraction issues. Nothing too serious, but more than I like.

 

[bobnob]

Just out of left field; your scale or powder thrower hasnt had a knock?

 

[Dthunter]

Bobnob:
Nope, everything is fine. I double check calibration every time I turn it on, and every 20 rounds or so.

 

[Skyshot]

DT what brass are you using. Saw the same thing when a buddy loaded some 7mmUltra. He seems to think it's the brass. He has been weighing the stuff now.

 

[Dthunter]

The brass I am using is from the early introduction of the 300 Ultra Mag.

I purchased 10 boxes of the 300 ammo, Had Patrick Ryan at Redding grind me
A custom set of 7-300ultra Dies.
Ordered a 7-300 Ultra Mag reamer from Clymer Maunufacturing.
My friend and I built these barrels before the 7mm Ultra exsisted. We were pushing the envelope at that time. I am sure Remington was testing the cartridge design in secret yet, but we just made them before it was officially introduced.

I have heard of problems with the early generation of Remington brass.

 

[bobnob]

Well it shoots like the blazes! A real hotrod. Makes my little 270 look like a wimp's gun!