Range Report Why do some bullets shoot tighter groups at longer distances?

[ronas]

Has anyone else experienced some bullets shooting tighter groups at longer distances?

Example shoot 1 MOA or a little better at 100 and 200 yards but then often shoot 1/2 MOA at 600 and 800 yards.

Bullets used are Lapua 155 Senars L with 44grs. of varget and Berger 175 VLD Target Match with 43 grs. of varget.

Do some bullets not stabilize until they are further downrange?

 

[KUSA]

It's probably the going to sleep thing.

 

[ultrarunner7]

Read Litzs book

 

[Fred_C_Dobbs]

There is not a complete agreement on this forum as to why this would occur. One explanation is that the marginally stable bullet experiences exaggerated coning/nutation/epicyclic swerving at short ranges, which dampens out as the bullet flies further. Another explanation is that the shooter approaches the short range shot more casually, and doesn't bear down and execute the proper shooting fundamentals until the range is more challenging. The latest prolonged discussion on the topic on The Hide started here.And there is enough information on the dynamics of a bullet in flight here to make your head hurt.

 

[40xs]

This has been discussed before on this forum. There are some who say that a bullet does not improve above it's performance out of the muzzle. What leads me to think otherwise is occurances such as; high speed wobble on motorcycles, watching the gyrations of a gyroscope at differing rpms. I had one as a kid ( havn't seen one lately), but you wound a string around the shaft and gave it a hard pull, set it down and watch it spin. it would perform differently at various rpms. Sometimes it would wobble at the faster turns and then level out at slower turns. Too many factors to draw a conclusion. How about tires on a car? sometimes you would notice a shimmy at a certain speed, but you either decrease your speed or maybe speed up and the shimmy would level out. I'm still not convinced that "bullets don't go to sleep".

 

[djskit]

I think one factor is when you get to the point of not being able to see the bullet holes, the psychology of shooting changes. Looking at those holes and thinking about how good or bad the group is can be distracting. Once you can no longer see the impact, you can focus on simply breaking a clean shot.