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Patch700
12-12-2014, 11:42 AM
Some blank paper along with a pen and a straight edge will make good enough targets to give a reasonable aim point.. bring a small level with you to the range and try to get them as plumb and level as possible .... If you are using a Caldwell lead sled then that might be another issue , the rifle needs to have some type of repeatable movement during recoil.

To add to this , a piece of string with a weight attached can be fastened to the backer board that you are using for target hanger... When I am doing load work up for a particular caliber I will bring a sheet of butchers paper and completely cover the target frame , then I take a nail and attach it to the top of the frame so as to have something to hang a plumb line from... Then using a straight edge I will draw a line that is on the edge of the plumb line , this line should be the entire length of the target paper , followed by a horizontal line that intersects which will be used as the aim point.

At this point I can now utilize one aim point on the plumb line and start shooting the various loads to see where they stack up vertically .

Example : 3 rounds at 38 grains of powder are 2" high of aim point
3 rounds at 38.5 grains are at 2.5" high of aim point
3 rounds at 39.0 grains are at 3" high of aim point
3 rounds at 39.5 grains are at 3" high of aim point
3 rounds at 40.0 grains are at 3.2" high of aim point
3 rounds at 40.5 grains are at 2.75" high of aim point and cases are showing pressure**

At this point I can deduce that there is a "Node" at between 39 grains and perhaps 39.5 and would mean that given a temperature change or what have you , if I stay in that 39.0-39.5 range I shouldn't see too much variation in my elevation (you could say that 39.3 would be a happy medium)

If at this point you still find that your groups are not as tight as they should be horizontally then that is where the seating depth test can shrink them possibly . (powder plays with vertical and seating depth plays with horizontal given the rifle is halfway accurate)

The seating depth test is quite simply done in the same manner but with a horizontal line instead of vertical.


Good luck.

gunrack
12-12-2014, 09:03 PM
Thanks Patch700 this is good stuff!

gunrack
12-12-2014, 09:20 PM
I did get to shoot after bedding the rifle yesterday and I have to say we had a much better day today. If I had been able to get solid I am sure the groups would have been better but this is a drastic improvement over what the rifle has done up to know.

http://i36.photobucket.com/albums/e17/blr32002/photo3_zps5eb02906.jpg

http://i36.photobucket.com/albums/e17/blr32002/4524350_zps833ff521.jpg

http://i36.photobucket.com/albums/e17/blr32002/45of4350015off_zps2f2c5227.jpg


http://i36.photobucket.com/albums/e17/blr32002/448of4350_020offlands_zps056d802e.jpg

Awesome group of .375"

http://i36.photobucket.com/albums/e17/blr32002/452of4350_zpsa4536fe2.jpg

Was going to be another dandy group but I pulled this one for sure. Knew it when the rifle fired.

Anyway it was a good day. I just got in from the farm and took time to post the pics before getting in the shower. I'd like to thank everyone that has offered help to me with this even though some of you did make fun of my targets......LOL Just kidding as you can see I did go spring for a package of targets but I am not at all crazy about the green....

scooterf79
12-13-2014, 10:22 AM
Awesome! Thats a little more like it. Glad its shooting better....job well done!
Scooter

murray brook
12-13-2014, 06:57 PM
My 7mm/08 really likes H-380 W760 and H-414.With the 168 sierra I often get less than 1/2 moa

LongRange
12-13-2014, 11:13 PM
Good to see your getting it dialed in now...just remember to only change one thing at a time or you will always be chasing loads.

GaCop
12-15-2014, 01:14 PM
I love a happy ending!

Patch700
12-15-2014, 08:53 PM
Very nice , always good to have folks report back on their findings so others can see definitively what worked for them... One thing for you to play with if you so choose with regards to working up loads is to always utilize the same aim point and NEVER do a scope adjustment , leaving the scope alone during testing will allow you to place targets side by side or even on top of each other to see if you are indeed sitting within a node..

Looking at your targets one could say that there is actually very little deviation windage wise and those that do have some are probably shooter error or possibly shooting without flags with A LOT of changes happening in the condition. This would dictate your probably rite where you want to be with your .020" off the lands.

You could try fine tuning the seating depth in .003" increments (.010" is too much of an increment to increase or decrease by as you may totally pass a node)
even your last group you shot at 45.2 , if you look where the flyer is it is exactly rite in the group elevation wise... Definitely worth dialing in and fine tuning that load!

Good luck