Are you reading the replies directed towards you Sleeplz? If your POI is shifting because of the barrel being impacted, you're either smacking the shit out of your barrel, or your Barloc/barrel aren't set up tight, as many folks have already described to you.
It's hard to quantify an impact otherwise I would do a more scientific test, but everything I have done shows no POI shift unless you get really out of hand, shouldered barrel and barloc. That is entirely dependent on the Barloc being set up properly to provide the correct amount of preload. Likewise for a shouldered barrel to be torqued.
What I'm getting at is that the Barloc works. You have to get pretty extreme to knock POI around provided that your barrel is machined correctly and the barloc is installed correctly. So if you're having problems, either you're installing it incorrectly, or your barrel is machined incorrectly. If it's on the shallow side of chamber depth it can cause the Barloc to give insufficient clamping force at the proper headspace. Do you want to solve the problem or just whine to a manufacturer on a public forum and ignore free help? Plenty of folks willing to help a guy out if you'd take the time to describe what you have (Provide pics of how your barloc is set up, torque specs, barrel manufacturer, shouldered vs. jam nut, etc..) and what is happening.