• This Forum is for adults 18 years of age or over. By continuing to use this Forum you are confirming that you are 18 or older. No content shall be viewed by any person under 18 in California.

Ladder test, 7-08AI

Dave in WI

Runs with scissors
Gold $$ Contributor
414118036.jpg

Ladder test on a 7-08AI I built. 700 action with Bartlein 3B 8.7 twist. Finished at 20" (I know, that's what owner wanted).
Hornady brass with WLR primers.
Berger 150 Classic Hunter at @2.737" COL just into lands.
VVN550 powder. Shot at 300yds. Slight wind from right.
1 42.0 2520
2 42.5 2614
3 43.0 2635
4 43.5 2661
5 44.0 2650
6 44.5 2645
7 45.0 2743 bolt started sticking a little
8 45.5 2795
9 46.0 2824

Thoughts and opinions appreciated!
 
At this point maybe three of each
Better yet, just take a day off
 

Attachments

  • IMG_0673.JPG
    IMG_0673.JPG
    468.2 KB · Views: 65
4-5-6 is my guess.

Whenever I run a Ladder, I shoot it twice back to back.
This way I can correlate the findings by proving the repeatability of the point of impact.
 
2-6 all look reasonable. Not sure how many rounds are through the barrel and it might be changing yet. Assuming it is low round count.

Three shot groups or a little seating depth work would be my next step. Both should provide more information.
 
With a factory barrel I would try a repeat of 4,5,6. But with that barrel and bullet I would load 10 of #5 shoot a 5 shot group, and then I shoot 5 single cold bore shots using the same target. My rifle the shots(cold bore) during a month. It's a good hunting rifle staying inside moa.
 
414118036.jpg

Ladder test on a 7-08AI I built. 700 action with Bartlein 3B 8.7 twist. Finished at 20" (I know, that's what owner wanted).
Hornady brass with WLR primers.
Berger 150 Classic Hunter at @2.737" COL just into lands.
VVN550 powder. Shot at 300yds. Slight wind from right.
1 42.0 2520
2 42.5 2614
3 43.0 2635
4 43.5 2661
5 44.0 2650
6 44.5 2645
7 45.0 2743 bolt started sticking a little
8 45.5 2795
9 46.0 2824

Thoughts and opinions appreciated!
414118036.jpg

Ladder test on a 7-08AI I built. 700 action with Bartlein 3B 8.7 twist. Finished at 20" (I know, that's what owner wanted).
Hornady brass with WLR primers.
Berger 150 Classic Hunter at @2.737" COL just into lands.
VVN550 powder. Shot at 300yds. Slight wind from right.
1 42.0 2520
2 42.5 2614
3 43.0 2635
4 43.5 2661
5 44.0 2650
6 44.5 2645
7 45.0 2743 bolt started sticking a little
8 45.5 2795
9 46.0 2824

Thoughts and opinions appreciated!
1) your incremental jumps are coarse. 2) you have decent vertical from 42.5 to 44.5 3) consider moving to 200 to take some of the vagaries of wind out of it, and run the ladder again with smaller increments. 4) likely to find the center of node across 0.4-0.6 gr 5) no ambient temp listed. The n550 is quite temp sensitive, thus caution at the upper end
 

Upgrades & Donations

This Forum's expenses are primarily paid by member contributions. You can upgrade your Forum membership in seconds. Gold and Silver members get unlimited FREE classifieds for one year. Gold members can upload custom avatars.


Click Upgrade Membership Button ABOVE to get Gold or Silver Status.

You can also donate any amount, large or small, with the button below. Include your Forum Name in the PayPal Notes field.


To DONATE by CHECK, or make a recurring donation, CLICK HERE to learn how.

Forum statistics

Threads
166,256
Messages
2,215,077
Members
79,496
Latest member
Bie
Back
Top