How do you test for accuracy w/ CO2 22xx's?

[T191032]

Ok, so this is what I'm wondering :  how do you go about testing the accuracy potential of a 12g CO2-fed 22xx pistol/carbine?

In looking over how I did the 3576, I shot a single 10-shot groups with different pellets, then moved on to the next pellet at 5Meter.  With the 2300KT .22 I apparently shot a 5-shot group per pellet then moved to the next one, then narrowed down the best groups to determine another round of shooting.  That's because of the inherent emptying of the CO2 12g cylinder.  Doing the pneumatic pumps were not dependant upon running out of gas.

I've never really run any extensive tests on my powder burners either, so shooting multiple groups of one brand/type to determine the whole accuracy thing isn't exactly ever been my thing - too much "recreational shooter", I know.

As I need to get a little more serious with the "1740 Target", I was thinking maybe 3 5 shot groups of one brand/type pellet, then move to the next, then to the next; as that would conform to a 45 shot string from a single CO2 12g cylinder, without the potential lose of air affecting group size, at the possible cost of some usage from that cylinder.

[quickster47 †]

I'm presuming that for different pellet testing you are placing your gun in a vise so that you are removed from the equation and only the pellet differences will show.  Is that true?

For the most part I always just pick a pellet and go from there.  For my 2300KT (.177 LW barrel) I use Vogel pellets.  For my 2300KT (.22 caliber) I ended up using and sticking with the RWS Meisterkugeln Standard .22 Cal, 14.0 grain pellets.  Although I did try the H&N Diabolo Sport .22 Cal, 13.73 grain pellets I went back to the RWS ones.  And of course, all these pellets are wadcutters.

Carl

[bdb12586]

I never do any real scientific tests but when I do any mods I only use about ¾ of the co2 cartridge so I know I’m as consistent as possible I would run about 30 pellets thru the gun then change cartridge and pellet type at the same time.

[T191032]

"I'm presuming that for different pellet testing you are placing your gun in a vise so that you are removed from the equation and only the pellet differences will show.  Is that true?"

No, don't have anything that elaborate.  My rest is the MTM pistol rest I normally use - http://www.mtmcase-gard.com/products/shooting/shooting-rests-pr.html  though the barrel seems to fit into the cutout for sling swivels pretty snugly.

[Darth]

IMH(umble)O, accuracy of a given gun (of any type) is a long drawn out procedure. To make a long story short … what you are doing is the right thing … but I would do at least 10 shot groups with a given pellet and note the AVERAGE group size then move on to a different pellet.  Keep good records, which it sounds like you do.

A chrony would most likely be the best tool for you … so you know (exactly) when the velocity starts to fall off and then stop there and install a new Co2 powerlet.

Be patient and keep shooting. After a whole summer of shooting a rifle of mine, I have determined that JSB Exacts work best in my Beeman R9 rifle (it’s a springer) … but it took “quite a while” to come to that determination. 

I bought about 20 different pellets of various weights and styles to come to that determination … and perhaps … a different pellet would do better.

Will you be using a “vise” all the time ?? I would shoot “as I would normally shoot” … again … In My Humble Opinion.

Darth