Please look at this target and give some advice...

[Tom W.]

I bought a PACT BBKII  Works well, and has an adapter so ypu don't need a battery,unless you just want one.

[Stan M.]

jonr,
 Jose had a good point about the bedding and the action shifting giving two points of impact. Your group with the factory rounds doesn't seem to be shifting the point of impact.
 I'd try keeping it simple first. Sounds like you need a dependable scale you can trust. Work on the loads some more and let us know what happens.
Scope parallax, I haven't experienced that problem yet. But have seen I Nikon Monarch drive a friend crazy on a 300 Win mag., that I helped sight in. Appeared to be sub M.O.A with factoty ammo. Then it went crazy on him a week later. Switched scopes and groups returned.
 Isn't this reloading mystery fun try to learn from it and not lose too much hair.
Good Luck,
Stan

[jonr]

I shot four 71 grn loads today. Max is 74.5. Same thing but tighter in each of the 2 groups.
One bullet hit 2" up of bullseye. The other two were 4" high of bullseye.
Then one 1 1/2" left of the two highest but on the same elevation.
I may have pulled that one left. It was the first shot. The others felt good when I pulled the trigger. I loaded four 72 grn's tonight and will try those the first of the week. All of the above mentioned shells were loaded on a brand new 5-0-5 RCBS scale. I like it MUCH better than the Lee and trust it more. With that said I do not believe that a varying powder charge is causing this.

Either:

1) The gun just does not like the lower powder charge

2) The action is moving some how

I could argue against both.
For instance, why would the action not move  the same on factory bullets.
You would also think that if it did not like the powder charge that it would just throw a wide group. Not two sperate but fairly tight groups.

Hmmm.....

Thanks for sticking with me on this everyone!

 

Jonr

[Stan M.]

jonr,
 Maybe you did not shoot enough of the factory loads for the action to move. If my memory is correct you only shot three factory rounds. Just another thought.
 I didn't think it would be a powder variation with such a large volume case. Glad you like the new scale, it will help build your confidence anyway and eliminate one of the factors.
Are you cleaning the bore before each session. That would help keep the varibles the same.  
If my science experiments would have been like this in school, maybe I would have had an intrest.  
Stan