My future father-in-law invited me up to Irvona, PA to shoot groundhogs on his porperty and I was wondering if I can use my varmit AR15 for this. He said he didn't think so. Can someone who knows the current regulations answer this for me? Thanks.

He is correct, you can't use semi-automatic weapons to hunt in PA (other than shotguns with the three shot plug for small game, etc).

OK, thanks!

Isn't there also an exception for semi-auto .22's for small game?

Nope...here's the link.
http://www.pgc.state.pa.us/pgc/lib/pgc/digestpdfs/2007/small_game.pdf

No semi automatic rifles are permitted for any hunting in PA. Nor can semi auto shotguns be used if they are loaded with a single projectile (slug). semi auto shotguns permitted provided shotshells are used and it is plug to a 3 shot capacity (1 chamber - 2 in mag.)

That is a lie and mis information. I used semi on my farm and was taken to court and guess who lost the case? The PGC did. I was allowed to protect my livelyhood with any ways I chose and without a license. I won that case to. I can hunt with any legally owned firearm on my property. Be it semi or what ever. Tey have no right to tell me what I use to eliminate damage to my property or livelyhood. That includes all predators or groundhogs that my livestock steps in their borrows and breaks a leg. Don't let them make BS laws up in their little convention that are illegal. Don't spread the rumor that these types of firearms can not be used outside of SGL. They can be used on private property with the owners consent. Again I won this case and the PGC is keeping it hush hush to keep their illegal laws seem legal,they are not legal laws.

It is neither "a lie" nor misinformation.

Regs state what they state and that is no semi auto rifles may be used for hunting, (unless one has a missing limb). In which case they can apply for a permit to hunt with a semi. Disabled people may also apply for a permit to hunt from a motorized vehicle, but they can only load the firearm when parked, not drive around with it loaded.

If you were found not guilty for using a semi for killing varmints or predators on your own farm, so be it. That does not change the hunting regs. Apparently the judge (at whatever level), decided you were not hunting but wereexercising your rights to protect livestock?

FWIW, any gas operated semi could be used for hunting, IF the firearm is modified to operate as a Manually-operated firearm. The regs don't ban semis, they merely require Manually-operatedrifles forhunting game. Semi-auto shotguns are legal for small game, waterfowl, etc. (not sure if theycan be used in SRAs for deer, would have to look it up?).

Some WCOs may consider any semi-auto rifle temporarilyconverted to manual operation to be legal. Others might insist it be permanently altered?

Yep,hunting is not the same and shooting animals for crop damage and giving someone else permission to shoot deer for crop damage won't cut it.

In the booklet you get with your hunting license it states under General Hunting Regulations .....
UNLAWFUL FIREARMS & DEVICES:
1) Automatic and semi-automatic (autoloading) rifles and handguns; 2) air or gas operated rifles and handguns.
It further states under Small Game with a note under Arms & Ammunition that: Rifle and handgun caliber restrictions do not apply when hunting woodchucks. While hunting small game during the bear or muzzleloader deer seasons, the only rifle or handgun that can be used is a 22 caliber or less rimfire.
Deer, turkey, waterfowl regs also list the firearms restrictions. In no case are you permitted to use a semi-automatic rifle. Period
The laws are quite plain, when we are talking HUNTING situations. If some judge or magistrate has decided otherwise, they are ignorant of the written law, or have had a compelling reason to overrule it, in my opinion.....