Help with strange grouping

[Ultramag45]

I am shooting a custom 338 RUM built by Mcwhorters... Nice gun... It shoots pretty well overall...Having some very funny grouping. though... 2 in 1 hole and a slight flier...doesnt matter what order i shoot them in either...every bullet, Accubonds, Bergers, ttsx..all grains of powder, different powder ,and different primers...funny thing is every group is an inch to 3/4.... and primarily in the same spot... 3 inches High at 100.... I can shoot 3 different loads with differnt powder and weight bullets and they are all within an inch of eachother.... Seen something like this before, and Knew it was a bedding problem.. not here though.. gun sits in a Macmillan, edge stock custom from Mcwhorters, Dont see any Pressure issues either.... ANYBODY GOT ANY IDEAS , gun)

 

[dragman]

Bad or improperly set up scope??? Either that or a bedding issue?? can you post up some pictures of the groups??

 

[wnc-coyote]

First thing we need to know is how you are shooting these groups. Are you letting rifle cool completely between each shot or are you cooling between groups? Clean/Dirty/Fouled barrel? Rest? I would start by checking out your scope really well. If that doesn't help you may want to try adjusting torque on your action screws. I had a similar problem to this once, found out I had been over tightening my rear action screw. Started using a torque wrench and set it the same every time I take it apart. Even though it is in a custom stock If it is not skim bedded I could possible see this happening.

 

[Stanm70]

Is the first shot the flyer or the last shot?

 

[Greyfox]

Its quite possibe that POI could be the same for various loads snd bullets, particularly at 100 yards. As to the flyer, I would try shooting at 200 yards. It might be caused by parallax effects. Also check the scope mounts, and perform a box test. This should help rule out scope effects which I have seen produce similar results to what you are describing. I have also seen this with a faulty shooting rest system, ie bipod bounce, or a loose rifle rest, hold, etc.

 

[Boom]

In addition to the other suggestions, I would try a five or ten shot group and see how or if the grouping continues to grow.
Good luck