Put my gun to a measured target yesterday for the first time, 50 yards. Best 15 shot group was 2 x 5 inches. Would it be correct to assume that the group at 100 yards would have been 4 x 10? And before anyone asks, yes I know I need a lot more practice...



Thanks

No.  There are too many variables involved to make such a claim.  The only way to know how your rifle/ammunition will group at a particular distance is to shoot from that distance.

Here is just one example for illustration.  The 10-shot group pictured below was fired from a distance of 50 yards.




Next, is a 10-shot group fired from 100 yards using the same rifle and ammunition.  As can be easily seen with the naked eye, the spread of this group is not an angular equivalent of the 50 yard group.






....

Would that be also true if you were shooting MOA at a 100 yards and then moved to 200 yards?

Theoretically, the answer to your question is yes. If you have a 1 inch group at 50 yards it will be 2 at 100, 4 at 200, 8 at 400, etc. However, as Molon says, other factors do come into play at longer distances and this method may not work perfectly. But again, in perfect conditions with appropriate scope power - so you can see the target well enough - and a solid rest, you could use such information to extrapolate a group at a given distance,

Skill can come into play,  as a good shooter may be able to extrapolate groups between 100yds and 200yds with minimum error... A novice can not. Start trying to extrapolate groups for larger gaps and the errors grow.

This all depends on a good rifle and ammunition... With perfect atmospheric conditions. If the rifle has a few moa spread and you use cheap ammo with its own moa spread... There is any wind blowing... Then you can not extrapolate groups at all.


BTW,  your group was 5 inches. You measure groups as a circle, the diameter of which,  is the distance between the two farthest shots.

Thanks for the input. Took it out again today and shot at 100 yards instead of 50. Best group was 3 inches, 2nd best was 2 inches except for one user error that opened it up to 5. I'm confident in the gun now, even more confident that I need a LOT more practice...