.25 vs .22 for groundhogs???

[mr007s]

I always suspected and have confirmed that if you fire a 25.4 pellet doing 940 fps from a Cricket carbine at a distance of 55 yards and it enters the right ear of a 12 lb, ground hog the afor mentioned 12 lb ground hog will be grave yard dead before its nose plows into the dusty earth.
Now you know and no need to fret over it

[n2omike]

I've shot lots of birds with both .22 and .25 airguns.  Always go for head shots. 

Two results...

1.  Bird seems to seize up!  Entire body tenses.  Feet tense around the branch, and it sits there for a second...  then flops over...  often still holding on the branch as it bleeds out the head...  and finally drops to the ground like a stone.  Have a picture of one from this summer still clenching a cicada in it's mouth after it hit the ground. 

These are generally shots where the entire cranial mass is emptied.

2.  Bird flops around for a while after a head shot.  Can do this for several seconds or more...  generally trying to fly with it's head in the dirt.  (instinct/muscle memory)

That's what BIRDS tend to do with head shots...  at least the one's I've shot. 

[CatbirdSHV]

Definitely prefer .25

No chucks around here, but I can say that my .25 has much more effect on varmints and even steel targets than my .22.  Would not trade one for the other, as they both have their strong points.

[wahoowad]

OP,

You generally will have more retained energy with a .25 than a .22, and that extra energy will be helpful in stopping a groundhog in it's tracks. Regardless, make sure you know where the groundhog brain is located and that you are capable of hitting it reliably out to whatever distance you will shoot them.

I spent all summer shooting them with my .25 Marauder and will say shot placement is critical. But they drop like a rock when you put one in the brain. Not their head, but in their brain. Go search for my posts in the Hunting forum for a little inspriatIon if you need it.