Originally Posted by
No.3
Need really to know a bit more info in all fairness - like how did you set the bipod up, surface it was used on etc etc.
What can happen if it's a Harris or Parker Hale style (legs fold up to the front) is that if the bipod is on hard ground and recoil pushes it rearwards the bipod can 'bounce' the muzzle up in the fraction of a second that the recoil can affect the flight of the bullet.
Technique is a big part of using a bipod, and as noted a stiff foreend that won't flex all over the show allows you to lean forwards into and 'load' the bipod which helps control the flip. A floppy standard plastic foreend will flex down and can do weird things at the action bedding area as well. Not that helpful.
Using sandbags is a much less reactive rest, more dead regardless of the technique you are using. If you are keeping the standard stock and want to use a bipod, the best chance of not shifting your point of impact all over the show is doing a stiffening job on it by bedding in a couple of carbon arrow shaft offcuts with some of the epiglass microballoon filler in it. Doesn't add much weight but really improves the stiffness factor of the foreend. Otherwise a floating or separate tripod with a u shaped rest that doesn't attach to the foreend is an option - it's a bit hard to drag sandbags around with you.