7mm-300 win mag load development

[FURMAN]

Ok guys, what would you do about this. There was too much mirage for 450yds so I shot these at 200 yds. These were some of the good looking loads from previous ladders. Assuming it will repeat this would not pass the OCW test. What do you think?

 

[AckleymanII]

Son, you have got some wind! Just look at the point of impact change!!!

Thanks for posting and would love to follow your load development!

 

[FURMAN]

Mirage indicated less than 3 mph and only 200 yds.

 

[FURMAN]

I went back out and shot these again at 100. 75.7 was in the .2s, 75.8 had two in the same hole and I shanked one, 75.9 was in the .4s. I will be going out to shoot this morning with 75.8 and different seating depths. I am currently getting little to no vertical with 75.7-75.9 but the horizontal is over 1MOA at 450yds with no wind. I shoot my wsm in these same conditions with .3 moa groups so I really feel the load for the 7-300 needs tweaked.

 

[FURMAN]

Well today the 75.8 .015 off(the depth the ladder was performed at) still had the horizontal. On the lands shot about .5 moa and .030 off was .3 moa. I will shoot again for repeatability but is appears seating depth was my issue.

 

[kev77]

What's your speed??

 

[Drop Port]

"I will shoot again for repeatability but is appears seating depth was my issue".

That's a good thing because the variation you are experiencing with a .2 tenth window (tuning of a load) with a case that large to me is a problem. It would be nice to have at least a 1/2 grain sweet spot.

 

[dinmax82]

What reamer and who chambered it?

 

[Danny1788]

What does 76.0gr and 76.2grs look like?