I have been using two Protektor Flat Top Dr. Rear Bags with the Slick Silver material, 1/2” and 3/4" ear spacing, and they have worked great for F-Open.
However, this past weekend I shot the lowest score I have shot since my early days of shooting F-T/R several years ago. While shooting (1000 yards), I blamed my poor performance on the variable wind, not paying attention to the fact that I had just shot two matches with decent results.
The Rear Bag was the culprit! (Well, not the bag itself.)
When I removed my 284W rifle to pack it away, I noticed that the rear bag rocked badly from side to side, and some front to back. I had noticed this when I first set it up, but at the time it did not appear anywhere as bad as it really was. The problem was the surface under my shooting mat, where I place the rear bag – it was a small mound, about 2" high. I had to setup my position about a foot from where I had set it previously, and this new surface was bad. To compensate for the rear bag sitting on the mound, I had to raise my front rest 2 inches higher than where it had been. No problem, I thought, not being aware of the instability of the ear bag. To shoot, I barely touch my shoulder against the stock, and barely feel the cheek piece, so the rifle is rather free to recoil. A wobbly rear bag definitely does not help maintain the rifle on target during the firing sequence.
Moral of my experience: Beware of how you setup your rear bag - ANY BAG, and what is underneath to keep it steady as you shoot.
Alex