30-378 Ladder Test

[James H]

Did a Ladder test with my 30-378 180gr Barnes TSX and 180gr Hornady IB bullets.
What do you Ladder test experts think. Starting load was 107gr Retumbo, load increment 1 grain, high on TSX was 113gr and 112 on IB.
All shots at 100 yards 1st shot on each from clean cold oiled barrel so I would throw out shot 1.
Barnes TSX

Shot 5 is between 3 and 4 and shot 2 is below shot 3.



Hornady IB

I am thinking I will just go with 111gr Retumbo with both bullets which would be shot 5.
The TSX bullets were very impressive. A .8" group for shots 2 through 6.
Looks like this rifle loves TSX bullets

 

[moosehunter]

I usually dont like to ladder at less than 200yds. And conditions allowing the more the merrier. At 100yds there just isnt enough dispersion to really see whats happening which Im sure you've noticed. Other than that it sure looks like you have a real shooter there. Id say redo the test at a greater distance and the "sweet spot" will jump right out at you. Also cut to 1/2gr. increments.

 

[James H]

I know most people use 200 yards or longer for the ladder test. I used 100 yards because I figured there would be a much bigger dispersion and the rifle shoots better than expected.
On the charge increases I assumed that with less than 1% increase with each charge would be sufficient.
Based on powder charge what is the normal percentage increases used with the ladder test.

I'm off to test the 111gr load at 2 or 300 yards.
If accuracy appears acceptable I think I am done.

 

[James H]

Well I tried the 111gr load. Conditions weren't so good wind 10 to 25 generally at 8:00 to 8:30 but from shooting point almost 6:00. Shouldn't have been even working on load development but I was excited at this A.M.s groups with the TSXs. The IBs actually shot better than the TSXs but I fired more rounds of TSXs. I know I missed the condition shooting the TSXs a couple of times not to mention being physically moved by the wind while shooting them. Conditions a little more consistant shooting the IBS.

Just under 1 moa with the IBs and just over 1 moa with the TSXs at 300 yards.
POI for both loads almost identical so I must be very close to a node. Velocities 3410 TSX 3420 IB, not too impressive for all the powder burned in my opinion.