How do I accurately measure for goup size?

[Tonykarter]

I think I am doing the measuring wrong.  Center to center?  I have been shooting some of the heavy H&N Baracudas and I guess I am printing my targets on the wrong type and weight of paper.  I'm using 60lb card stock (I think it is 60lb) and the Baracuda's really rip the paper down much more than my other round-nose pellets.  No backing board either, just the cheap Crosman metal cone pellet trap, so I guess I need to upgrade there too.

So, best way to accurately measure group size?

[GatorCountry]

Card stock paper or just computer paper on a backing of thin cardboard from a boxed food (ex cereal) works well.  Then measure the pattern at it's widest and subtract by one pellet diameter for the center-to-center value.

[cosmic]

https://ontargetshooting.com for windows only...

[Mole2017]

Getting the right paper and back stop makes a huge difference. I once went on a paper testing kick--every sheet of whatever I found about the house or office was a potential candidate for printing targets. In the end, I found two that did really well on their own, i.e. no backer. The two winners were a drawing paper by "Marseilles Studios" (just about perfect holes, like they were punched) and Wausau card stock, which sometimes only flaked a little, but took very nice holes from wadcutters. Conventional air rifle target paper? Worthless in comparison--too fuzzy and weak. However, one target paper by Edelmann did well, if I recall correctly.

But add a backer and lots of things improve.  A backer of cardboard, plastic "cardboard" for signs, or even just more paper, is all that is needed. I find the cardboard can be shot up quite a lot before you have to replace it.

You can measure center-center, if you can estimate the center, or like Mark suggests, measure the pattern, outside edge to outside edge (think like the diameter of the circle that barely covers the holes of in the group), and subtract the diameter of one pellet. That would especially help if you are dealing with a "ragged hole" group.

[desmobob]

A fun and easy way to do it is to use an app like TargetScan.  If you use standard targets, the app will score your shooting, measure your group size, show the center of your group and offer windage and elevation adjustment recommendations, etc.  You just photograph the target with your phone and the app does all the work.

Tight groups,
Bob

[Sfttailrdr46]

  If you stack them inside a single pellet size hole no need to worry about group size and believe it or not there are a few members that have achieved that lofty goal at 25 yards. I am not one of them. but the above descriptions apply

[nervoustrigger]

It's a magical thing when that happens.  I've only done it once at 25 yards and it was with a QB79 and Air Arms 8.4gr

[kbstingwing]

I found it much cheaper to do group sizing on Rat heads, if the the Rats head is just about gone, then your grouping is good, and I didn't waste any good computer paper....

[archellas]

If you stack them inside a single pellet size hole no need to worry about group size and believe it or not there are a few members that have achieved that lofty goal at 25 yards. I am not one of them. but the above descriptions apply

No, no ... I like to SEE where I punch paper!     It's very disappointing when they go through the same hole, you can't tell if you hit the target or forgot to put in a pellet!  I mean, I've done it once or maybe even twice (two different occasions - not more shots through the same hole, mind you)
LOL

[Kailua]

I have used adhesive shelving paper (thin vinyl type)  for a backing and leaves pretty clean holes. jmo

[K.O.]

Me being the sensitive artistic guy I am.. ... I hate it when your clover leaf turns into a ragged hole... but man it feels good when you pull off a five shot clover.. I do get more 4 leaf clover than 3 with my 5 shot groups..

[shooter r]

You will know if you are shooting good. Numbers are numbers, tight groups from a certain distance, any distance, that makes you think: "NICE!",  is what you want.

[JoeV]

If you’re killing what you’re shooting at, the grouping is just fine.👍👍

[Booger]

It's a magical thing when that happens.  I've only done it once at 25 yards and it was with a QB79 and Air Arms 8.4gr

This is the best I can do, I am sure others can do better.

[archellas]

If you’re killing what you’re shooting at, the grouping is just fine.👍👍

+1

This is the best I can do, I am sure others can do better.

Nice shooting! I got a hole like that once, but then I had to recharge my power drill! Oh ...., you did that with an ... airgun ........ never mind (in Emily Lettila voice) LOL

TJ

[Tonykarter]

Thanks guys!  It's Saturday morning: My time to go out in the yard, punch some holes and put this all to good use.