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Air rifle group size

Posted: Thu Sep 22, 2011 10:46 pm
by WesternGrizzly
What kind of groups should I be looking for when I test pellets? I did some testing this week and the best lot averaged a 6.126mm group (mean of 5 ten shot groups).
Matt

Posted: Fri Sep 23, 2011 5:49 am
by sbrmike
I have tested various pellets in various guns through the years. Some test single pellet(nominal 4.5mm) hole groups and others up to nearly three pellet widths. As with anything as far as shooting, it depends what you are wanting. To win at the top levels you need tiny single pellet size groups. For me as long as the pellets group 1-1/2 pellet size, which is about what you are reporting is good enough for me, although it won't win matches at the top levels.

I know some folks test with a chronograph. I do both group and chrono and there is a relationship, but my rest and method is not foolproof, sometimes the best group is not the pellet with the lowest extreme spread velocity wise. I tested some lots about a month ago and one lot yielded .2 fps extreme spread. It shot nicely but another lot shot single pellet hole groups with a bit higher extreme spread. I had posted that info here a while back. This was done outdoors so wind and other variables had some effect.

Posted: Fri Sep 23, 2011 6:52 am
by robf
how are you testing?

Posted: Fri Sep 23, 2011 10:11 am
by sbrmike
I test 5-10 shot groups from a Hoppe front tripod and rear bag @10m. I test the lots in random order to try and keep things honest.

Posted: Fri Sep 23, 2011 3:19 pm
by WesternGrizzly
I test with a machine rest at 10 Meters. 5 ten shot groups at 10Meters
Matt