112 .338 LM Group Sizes

[CFJunkie]

I'm also left eye dominant but shoot right-handed.
I control the trigger better with my right hand so I shoot right-handed.
I shoot pistols using my left-eye but still shoot right-handed.

I close my left eye when shooting to minimize the confusion when target shooting.
Works for me.

[GaCop]

I'm glad to see you have the .338 LM under control.
Your latest group shows you big improvement and it appears that your rifle likes that ammo.
It also could mean that your rifle is wearing in - most of my Savages take at least 20 rounds before they are shooting at their best.

Barrel heating may be causing the one-out condition, but based on my own experiences, I would bet it has more to do with set-up movement as you complete the 5-round group.
After years of shooting and measuring, I no longer immediately blame the rifle, ammo, temperature, powder or bullets when I let one bullet out of a tight group.

I find that when any of my barrels heat up, the bullet drops a bit. I use temperature strips on my target barrels to determine relative change in barrel temperature.
My rifles shoot best with barrel temps from 85 to 105 degrees.
Over 120 degrees, the bullets tend to drop about 1/8 to 1/4 of an inch. They never seem to rise.
I suspect that the barrel bore might be expanding just a bit and the pressure is dropping a bit.

Hint, if temperature is affecting your POI, you can still shoot tight groups - they just won't group at your POA.
The danger is that if the barrel gets too hot, it will copper up very quickly and you will also create the condition for erosion or even flaking at the chamber to bore transition.

Based upon my experience, if I see a bullet rise, I automatically assume I snuck up on the scope. A 1/8 inch move closer to the eyepiece moves my bullets up 1/4 inch.
That is very easy to do with a recoiling rifle.

To my eliminate shooter induced variations that cause bullets to rise or drop unexpectedly, I have adopted this drill.
I set up and get in position - and get ready to shoot.
Then I lean my head back just enough to see the black ring at the periphery of the scope.
If it is concentric, I know I am in the center of the optical plane.
If it isn't, I move my head slightly until the black ring is concentric.
Then move my head forward just enough until the ring disappears - keeping the ring concentric as I move forward.
That puts me in the center of the optical plane at the same eye relief position every time.
Then I pull the trigger.

I admit that when I am shooting well, I sometimes forget to go through that process and almost always find one bullet go slightly higher, usually toward the end of an otherwise tight 5-round group.
It happens the most with my heavier recoiling rifles, but I now use the drill on all my rifles now, even my target .22LRs.
Paying attention to my set-up technique has reduced my group averages by 50% with my higher recoil rifles. Good information!

[Dave Hoback]

I'm also left eye dominant but shoot right-handed.
I control the trigger better with my right hand so I shoot right-handed.
I shoot pistols using my left-eye but still shoot right-handed.

I close my left eye when shooting to minimize the confusion when target shooting.
Works for me.

When I was instructing, I trained many people with this very issue. It’s actually quite common… “Cross-Eye Dominant” . And very easy to spot. I’d have a student shooting good groups, but always a couple inches LEFT of POI. And they just couldn’t figure out why. So I would instruct how to index the sights from 12 to 11 o’clock. Like magic, their groups would be right on POI! Man.. the look on their face after. Like a kid on Christmas! Good times:redface-new:

[Ernest T]

.... My only gripe is the rifle is so expensive to shoot. Recent ammunition purchases were $7-8 a round. It's got me looking at other rifles for the time being until reloads are possible or ammo pricing comes down.

That's the reason I went with 6.5 Creedmoor on my new rifle. I really wanted a 338 Lapua, but the cost of rounds dissuaded me from that notion. You made some good improvement there.