help reading first ladder test.

[42769vette]

cal 7mm rem mag
powder h4831
bullet 160gr game king
col 3.248
rifle factory rem 700 adl
range 215yds
temp 83 and very little wind

this is my first time doing a ladder test and im not sure how to read what i shouldload next. hodgen says min is 58gr and max is 60gr. no load showed the least little sign of pressure. and i gave a minute or 2 cooling time between shots

i loaded in .4 gr incrments

gr velcity poi

58 2493 5.5 low-.3 left

58.4 2508 3.3 low-.2 right

58.8 error 4 low-.4 right

59.2 2495 3 low-.3 left

59.6 2545 3 low-.2 left (trigger jerk)

60 2537 1 low-.5 right

are these resolte so scattered i need to start from scratch and load some a little hotter?

 

[Engine 22]

Re: help reading first ladder test.

Your velocities seem pretty slow. I recommend trying a different powder such as Reloader 25.

 

[42769vette]

Re: help reading first ladder test.

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Engine22</div><div class="ubbcode-body">Your velocities seem pretty slow. I recommend trying a different powder such as Reloader 25. </div></div>

http://www.snipershide.com/forum/ubbthreads.php?ubb=showflat&Number=2008718&gonew=1#UNREAD

my velocity was part 2 of my question

 

[vman]

Re: help reading first ladder test.

Vette if you could get a pic up that would be great

and for the record, wind does not matter so only look at the VERTICAL not the horizontal.

The ladder looks to find the variable to reduce vertical spread, ie consistant bullet drop via finding the barrels relaxed state of harmonics.

Also, your first countable shot should be hitting low, and the following rounds climbing up slightly.

Take your time if you need to, and if possible take it out past 100 yards.. 200-300 is good.

Look for the powder charges that create a group like effect. That will be indicative of a rough accuracy node.

Once you have found this, work around that area and study it further to find the optimal powder load.

 

[dpreston]

Re: help reading first ladder test.

If you can get the distance, I would go atleast 300 (400-500 better). With my 7WSM at 400 yards, I had 3 different charges within 1 inch of vertical.

+1 on trying a different powder. You should be atleast at 2800 fps. If you have any RL-22 that will do the trick for the 160's. With my 7 rem mag. I started around 61 grains and worked up. My 7 rem. mag hunting load is 160 accubonds at 65 grains of RL-22 and I'm around 3000 fps.

 

[42769vette]

Re: help reading first ladder test.

after another thread i think my chrono is screwed up mabye a low battery.

i really can get much range until we harvest, after harvest i ca shoot 750-800 yds. i need the load for a october 2nd hunt and we wont harvest till mid october

 

[SSC]

Re: help reading first ladder test.

how far of a shot are you looking at for the hunt in early oct. if it isn't too far I would just shoot groups till you find a good one for the hunt and then do the ladder at 600.

 

[42769vette]

Re: help reading first ladder test.

i plan on about 250 yd shot. thats why i thought i should do all load development at 250

 

[42769vette]

Re: help reading first ladder test.

update. i shot today using everything the same except i went by .3gr incrments at 250 yds. i went from 60 (hodgens stated max) to 63gr of h 4831. im still not seing any pressure, but all 11 rds fired at 250 yds fell in a 2 inch vertical spread so im guessing my rifle likes what ever i decide to feed it. im still going to load hotter until i see at least some sign of pressure