Two grouping ?

[Brandon_M]

I having problems with a 243AI. Its what I call two grouping, witch is that its shooting two small groups a half inch apart. Shot one will go to the right, shot two will go to the left, shot three will go in hole one, it will go back and forth like that for five shots.

A little more info.

Fire Forming load
R-P brass
vv n-140
cci 200 primers
87 gr vmax bullets

I'm just getting started on this one. Am I asking too much from a fire forming load.

Thanks for the help

 

[LHSmith]

Am I asking too much from a fire forming load.


[/quote]


Yes.

 

[Klong]

"Am I asking too much from a fire forming load."

Maybe!

Could be shooter/bag issue. Could be parallax or bullet seating depth. Not enough information. What distance? How clean is the barrel? Using a bipod or bags? You could eliminate the shooter issue if you can have someone else shoot it and it shoots the same pattern. Are you compensating for wind? If your front rest is bags, is everything tight? What kind of trigger pull do you have?

This is what I would do:

1> Have someone else shoot it if possible.
2> Tighten or loosen stock bolts
3> Check parallax
4> Change load up or down .2 gr
5> Change bullets or bullet seating depth

Good luck! Let us know what you find out?

 

[Brandon_M]

Its a new barrel only 49 rounds. I shot 1 and cleaned for the first five for shots 5-25 I shot five and cleaned the last 24 was not cleaned.

At a lower load it done the same thing so shortened the oal(cant go longer) then the group opened up so I added .5 grs more and it went back to two grouping(all shooting was done a 100y off of sand bags front and rear)

Its a shilen select match 1:8. I had quite a few of the 87 grainers from a earlier project I was hoping to fire form with. I may just have to go to the 105 hunting bergers.

My other 2 ackley calibers I always use the c.o.w. method to form brass.

 

[cmillard]

can't expect a whole lot from r-p brass. i think its junk

 

[Nomo4me]

AMEN to that. I just processed several hundred for my .204. I had to toss 20% of them for extremely uneven neck thickness - like .012" on one side vs. .005" on the other.

Not only will I never buy rem brass again, I don't think I'll take on another gun that Lapua doesn't make brass for.

can't expect a whole lot from r-p brass. i think its junk

 

[rogn]

You may want to try another scope if tightening and checking and changing shooters doesnt prove out. Ive had a major brand scope do this with 2 different units. The reticle cell(?)(dont know what else to call it) will shift back and forth on recoil, giving 2 separate groups-each group is representative of rifles accuracy/precision, but youve got 2 differentt points of impact. I suppose this could occur at the extreme ends of adjustment more easily than in the center.

 

[DOGCAPPER]

Have a 260 Rem that I ran a Ackley reamer thru...
Shot up a pound of RL 22 and over 100 Berger 140s...
2 and 3 inchgroups at 200 double groups...
Put an old Leup on it and went to grouping nice...
Mfg replaced turrents and erector assembley ....Thats three Weaver T 36 with problems my shooting buddy and I have had in the last 8 months......
LT

 

[btm_54]

AMEN to that. I just processed several hundred for my .204. I had to toss 20% of them for extremely uneven neck thickness - like .012" on one side vs. .005" on the other.

Not only will I never buy rem brass again, I don't think I'll take on another gun that Lapua doesn't make brass for.

can't expect a whole lot from r-p brass. i think its junk

+1 re Lapua idea

 

[gunrac]

I'm guessing a parallax issue. Didn't catch what scope you are using.

A lot of scopes are set up w/a 150 yd. parallax, unless you are using a AO "adjustable objective" scope. Don't expect the yardage marks on the AO to be exact either, it's rare that they ever are.

It's easy to check. Set your cross hairs on the target. Without touching the gun, look thru the scope, bob your head up an down, then side to side. If your cross hairs move any at all, your parallax is not correct. You can adjust an AO to get it perfect, w/o one you'll just have to learn to do your best to square in behind it.

 

[necchi]

For What It's Worth,

When I see Left-Right groupings,,it's Me on the trigger

 

[skeetlee]

It could be a lot of things really. How was the wind today? What type of set up are you shooting from? What twist is your barrel? Are you using the best bullet for that twist? seating depth, parallax, scope rings, scope, neck tension, brass. It truly is endless. Get some good brass, shoot the best bullets shoot from a solid rest, get some wind flags, learn to use them, try different seating depths. do everything you can, and start eliminating the obvious. How many groups did you shoot that were separated? One or two groups doesnt really mean much. 6 or 7 and then you probably have some issues. Fireforming is also a possibility. I have had rifles that shot really good while fireforming, i dont think it has much to do with that but maybe?? do some work! That's one thing i really enjoy about rifles and reloading. Good luck!! Lee

 

[glo]

Bed your base and lap your rings. That always works for me.

 

[skeetlee]

good point glo. Beading is another key area!

 

[Brandon_M]

I've switched bullets, scopes, and powder. With little change.
I can get a OK group(.750) but if I change anything to try to make it better it starts to two group again.
Ive got a different stock on the way, I'll do more shooting after it gets here.

 

[glo]

Bed your base, bed your base, bed your base!!!

You can do a quick check of your base (1 piece) by taking all the screws out, then put the very front screw in and torque it down. Then measure for a gap at the rear of the base between it and the top of the receiver.

Next, unscrew the base. Then put the very rear screw in and torque it down. Then measure for a gap at the front of the base between it and the top of the receiver.

Next let us know how much of a gap you’ve found. ;D

My stock Remington 700’s have from between 10 and 40 thousandths of an inch gap.

 

[Brandon_M]

TWO PIECE BASE with Burris signature rings

 

[Brute]

My experience has been it's usually an action bedding issue when I get two distinct groups.

 

[skeetlee]

is your rifle beaded and is the barrel free floating? Lee

 

[Brandon_M]

The stock I currently have is for two barreled actions, it has a aluminum bedding block, and the barrel is free floated.

I have a stock on the way solely for it that I will bed.