Question on Group size at different yardage's

**rdfkentucky** · 04-09-2017, 09:34 PM

I purchased a Savage 10 FCP-SR in 6.5 Creedmoor. I'm breaking in the barrel by following Savage's web site. The other day I did the shoot one and clean for 10 rounds. Today I got to shot 3 rounds and clean for a total of 12 rounds. I placed a target to shoot into at 50 yards. I usually shoot at 100 yards but didn't have a place to shoot today. Shooting groups at 50 yards, what does that tell me compared to shooting at 100 yards?

Rick

**sharpshooter** · 04-09-2017, 10:29 PM

Absolutely nothing.

**Deadshot2** · 04-09-2017, 11:35 PM

When people start universally using angular measurement for groups the answer will be clear.

Angular measurement is the same, whether 50 yards or 500 yards with the only variations being shooter and conditions.

If you shoot regularly 1" groups at 100 yards then you will most likely see groups close to 1/2" at 50 yards. If you shoot a .5 MOA group at 100 yards and all conditions are the same, you should shoot .5 MOA groups at 50 yards, 500 yards, or even at 1,000 yards, again all other factors being the same.\\

Thinking in "Inches" is a holdover from the days where ammo was stuffed into the front of a rifle. Today it's best to think "angular" either in MOA or Milliradians (Milrad) and of course, make your next scope one that uses those values on both turrets and reticle.

**Texas10** · 04-10-2017, 09:14 AM

One minute of angle is 1.047" at 100 yds, and half that at 50 yds. So if you want to move the bullet impact, for instance one inch left at 50 yds, you dial in TWO minutes of correction, and to move it one inch left at 200 yds, you dial in one HALF minute.

Some scopes turrets are calibrated in inches instead of Minute of angle. If your scopes turrets say 1/4" per click, they will be a bit short of one minute of angle per each 4 clicks. This can be a factor when you start dialing in 20 MOA of elevation to reach a distant target (20 X .047 = .94 inch)

As other state, try to select a scope with turrets and reticle calibrated in the same scale. MOA or Mil, whichever you prefer.

**joeb33050** · 04-10-2017, 10:36 AM

Group size does not linearly vary with range. Double the range and group size more than doubles. Some CBA NM records showed the following:
5 shot 100 yard groups are .45 times as large as 5 shot 200 yard groups.
5 shot 200 yard groups are 2.2 times as large as 5 shot 100 yard groups.
10 shot 100 yard groups are .43 times as large as 10 shot 200 yard groups.
10 shot 200 yard groups are 2.35 times as large as 10 shot 100 yard groups.
On average

The reason for this is that movement away from center is caused by first, an acceleration and then the resulting velocity. The acceleration and velocity can be thought of as being at (any) direction perpendicular to the bore axis.

joe b.

**RC20** · 04-10-2017, 10:59 AM

If its a 1 inch group at 50, theoretically it should be a 2 inch at 100.

There is some scope aspects that play in where you can see and shoot better at 50 than 100 so it gets iffy, but the math part is true.

The above is new to me but may factor in there as well.

You certainly can make scope adjustments at 50 and get it danged close to being on at 100 (average rifle velocity)

I can shoot a 22 at 50 yds at just a big under 1 MOA, it goes wild out at 100 with more like 3 and 4 MOA.

I can't see iron sight at 100 real well, but I can get an orange ball on a black roundel at 50 yds and shoot my old 1917 pretty good, even out to 75 yds.

At 100 it falls off pretty badly.

**rdfkentucky** · 04-10-2017, 09:18 PM

Thanks

I've never shot at 50 yards with a center fire rifle, and didn't remember reading anything about it and just was curious.

Rick

**Jamie** · 05-06-2017, 11:45 AM

I had a TC Encore pistol in 30-06 SPRG and 50 yard shooting one day taught me that group size does not necessarily follow logic, That gun shot the same group size at 50 as it did at 100 yards. Bullets move around in flight more than most think. That was about 20 years ago but since then I have had rifles that would shoot smaller MOA at 600 yards than they would at 100 yards and I have had the exact opposite.