My 270wsm is shooting great off a rock rest with a bag under the rear, I didnt have my bipods at the range to try, I am missing way to many easy 150-200 yard shots on groundhogs, Is it possible that the bipod is making the gun shoot different?

Yes

Do a search on shooting sticks and you'll find out more than you want about technique.

Mostly your group will open up and move a bunch!

BNagel

I can't be certain, but I believe that different pressure on the forend would cause the rifle to group differently. When I plan to use a bipod on a hunt I always shoot it in at the range.

I went to the range and it was still dead on from the bench but about 4 inches high with the bipods, i got er dialed in now.

quote:

Originally posted by Benwillweit:
I went to the range and it was still dead on from the bench but about 4 inches high with the bipods, i got er dialed in now.

Good on ya, mate.....

ive also heard that soft vs hard ground can make a difference. im lucky, my half inch groups opened up to 3/4 but POI was the same. dunno how that happened maybe it was a fluke that day

I shoot a pistol and rifles with bipods and a lot of things can happen. First you need to sight in using it since the added weight makes a big difference. Sitting at a bench is nothing like sitting in the field and shooting prone in the field is even worse. Sometimes you may push or pull on the rifle depending on the terrain or the rifle may not be as level. The angle of the butt stock against your shoulder also has an effect on your poi as well as the change of your grip. If I'm going to shoot prone in the field with a bipod, once I'm sighted in at the range from a bench to check groups I shoot prone to simulate my hunting conditions as best as possible. I've always found a shift in the poi doing this when conditions change.

quote:

Originally posted by Benwillweit:
My 270wsm is shooting great off a rock rest with a bag under the rear, I didnt have my bipods at the range to try, I am missing way to many easy 150-200 yard shots on groundhogs, Is it possible that the bipod is making the gun shoot different?

By the time the bullet has left the barrel, the rifle has already recoiled a small distance. Whether it comes straight back or lifts the muzzle has a lot to do with point of impact. It is unlikely to shoot the same with sandbags as with a bipod fixed to the stock. If the bipod is fixed to the barrel it's guaranteed to shoot differently.

I have a Mini-14 that had the sling fixed to the barrel block, and it would pull the barrel to the left when I shot with the sling. I later moved the attachment point onto the wood stock, and while the groups are still not good, they're centered.