So Yup. Speaking for myself. I have ignored it so far...well as I have said earlier, I experimented and found no advantage for me...and despite your and

@Sonicdmb73 's much valued contributions, this thread for one, has not produced much evidence to show that there is any demonstrable advantage with statistics and recorded results to back it up has it?

I do seem to remember reading an article that was talking about seating depth...the gist being that the amount of support and guidance given to the bullet by the case neck was more important than any reduction of the distance to the lands, and that seemed to make sense to me.

This is the reloading forum of the Stalking Directory so I presume that most reading and following this thread are loading for a stalking rifle rather than a bench rest or varmint gun...and that most will be shooting at deer below 200metres if not 100. So it would be interesting to find just how many find adjusting the seating depth improves things over a reasonable number of groups and what the variation group to group is on good or bad days.

Having read the excellent Fuller analysis of groups article a few years ago (

Shooting - Group diagnosis ) I have set much more store in the quantity of results and the average over time rather than just the best group achieved. I would like to think that I could reproduce the same group every time but, the numbers and my folder full of targets do not lie.

I have come to the conclusion that I am good for 1/2" and the rifle and ammunition are good for 1/2" so although most will cluster, the groups will still go out to 1" from point of aim if both the rifle and I are on our extremes. With the worst group just over 1MOA I know that most of my bullets will be less than 1/2 MOA from the trajectory so for chest shot deer to 200 metres I should have a good margin for error.

Although there are arguments and even formulae for including or excluding fliers and outliers (see below)...I am reloading for a hunting rifle so sadly for my ego, every shot of every group counts however wide...I must work to the worst group I have achieved with the knowledge that there is every chance I will do better when I actually point it at a deer.

Thank you for sticking with it!

Alan

**OUTLIERS IN GROUP TESTING: WHEN TO EXCLUDE FLYERS**

by Joe Brennan
*Sometimes during a test we get a group with one shot way out, an outlier.*

Our choice is whether or not to INCLUDE that outlier group in our results/calculations.

Here's a simple rule for 5 shot groups:

On the outlier target, measure the smallest 4 shot group and the 5 shot group including the outlier.

Divide the smaller into the larger.

If the answer is more than 1.7, DON’T INCLUDE the group.

If the answer is less than 1.7, INCLUDE the group.

Here's an example: A set of 5 shot groups has one group with a very wide shot. The four shot group size is .8". The five shot group size is 1.5". Dividing .8" into 1.5" we get 1.875.

Since 1.875 is more than 1.7, DON'T INCUDE the group.

For 10 shot groups, measure the nine and ten shot group sizes, divide the smaller into the larger. If the result is more than 1.43, DON'T INCLUDE; if less than 1.43, INCLUDE the group.

WHY?

A 5 shot group is 1.1 times the size of a 4 shot group.

A 10 shot group is 1.03 times the size of a 9 shot group.

The standard deviation of 5 shot groups is .269 X the average.

The standard deviation of 10 shot groups is .195 X the average.