i very excitedly went down to the range today to test my first batch of reloads .308 win using 150 grain winchester power points adi ar2208 and pmc lr primers i loaded 4 going up .5 grains at a time started with 44.5 grains, it sprayed every where, about 5 to 6 inch group 45 grains about 3 to 4 inch group 45.5 grains 1 way left then 3 about 1 inch group 46 grains 4 to 5 inch group then 46.5 grains 1 way left and 3 under moa! thats as high as i had prepared and did not want to push my luck as at 46.5 grains i could feel the powder compressing into the case.
now my questions, why the good group at 45.5 and 46.5 but 46.0 so loose? and why the first one going way left? i had not cleaned between groups was that my mistake?
the primer seemed to be a little flater on the 46.5 but dunno exatly what i am looking for, adi states the do not exceed load is 47 grains so its not a hot load at 46.5
all in all it has been a pleasing experence and i am keen to experement more but some advise will be useful thanks in advance, greg

That a big group could be the rifle check all screws. Could be the scope if your using one. If not open sights 4 inchs could be it for your eyes. Could be the shooter you might have some one else try it.

How does it shoot with factory.

greghud, welcome to the forum and to the world of reloading!
Could you give us a little more info on your rig?
Powder compressing in the case is not always a bad thing but, I try to use a powder that will fill between 80 and 90%. If you have some feeling that the bolt is hard to open, even a little, you are getting into pressure. A flat primer from normal is going to be different that a primer that is flattened from pressure.
As far as "loose" groups, that is why we reload. What is going on is you are trying to match the vibration of the barrel with the exit of the bullet and with the powder burn rate and barrel time of the bullet.
If you do not have Lymans reloading book, I highly recommend it. It will explain primers and waht to look for. It aslo has info on, well it has a lot of great info.
And just so ya know, by even changing one componant, you can either open the group or shrink the group.

Keep asking the questions and we will try to help!


Smedley

Welcome to the world of reloading. Beware, it can become addicting.
Give us some more info on your setup. There are alot of variables to factor in, the gun, scope, rings, bullet, powder, benchrest, etc.
Given the group sizes you are getting, I have a feeling it's an issue with the scope if it has one or the type of benchrest you're using JIMO. Also, at what distance are you shooting the groups at?

With groups ranging from 1" to 6" with only small variations in powder charge,I suspect another problem with the gun or the sighting system.

The problem I see half the time, is the scope mount to receiver screws are loose, and cannot be detected without removeing the scope and ringes.

What does it all mean?
You may have a screw loose.

sorry for the long wait for a reply, we have had a cyclone blowing by so i have been busy
the scope is not the problem as i re tried the load at 46.5 and it shot a group of 3 touching and with factory loads it usualy shoots well. i think that it may be the barrel getting hot as it is a light weight hunter. the loads were .5 grains apart is to much? should i be going up in .2 grains increments? i am working on a load that will shoot well for hunting pigs mostly, not for bench rest comps.
all in all the gun works well with highland and fedral factory loaded 150 grain soft points.
so i am working on emulating those or maby going better.
thanks for the info so far, greg

I doubt it's the barrel getting hot...I think it's your load.

First of all, I'm not impressed with PMC cases. I've never used them but PMC primers may be no better. Secondly, the particular powder you use in the .308 Win. can make a big difference. I load for an M1A and an Encore in .308 Winchester. The powders I've found to work the best are IMR 4064 (for both) and Winchester 760 with heavier bullets (don't use this slow a powder in the M1A) in the Encore. I use Federal 210M match primers but other brands would probably work just as well.

The bullets you use can also make a big difference. For varmint/target work, I like 168 grain Nosler match bullets. I would probably go with 165 grain Hornady Interbonds for hunting.

Check your primer flash holes when you deprime the used cases. I processed a bunch of 44 Mag. cases recently. I threw away EVERY PMC case because the flash holes were eccentric (not centered perfectly in the primer pocket). I will probably never buy PMC brass/ammo again.

What I've found to be true most of the time is that with a powder charge a little too low, accuracy is poor. As the charge is increased, the point of impact of the bullets will change and the groups will tighten. Then with even higher charges, the groups will start to widen again. I stop at the load that gives me the best groups which many times is several grains less that what is listed in the manual as a maximum charge (though sometimes I've gone a little over the maximum charge to hit the sweet spot). Of course, if you get sticky cases, pierced primers, etc. you don't want to push things any further.

thanks for that info grumulikin
i have got some fedral primers now so i will try a batch with those, do i load 46.5 again or try diferent charges again?
where i live access to diffent brands can be an issue we only have 3 shops, one i refuse to deal with, so that leaves 2 and they dont stock much so its kinda u get whats there or nothing.
the adi powder is an ozzy company and seams to be popular localy, dont mean there good or bad just available.
i will have a look for diferent projectiles and see if that helps but the load at 46.5 that i reshot worked realy well again. so maby its just that load is fussy and needs to be spot on. to shoot well and at 46.5 thats the point?