I've had a few BLR's some pistol grip some straight grip. Most had quite good accuracy. One was a 7mm-08REM with a pistol grip was exceptionally accurate. One day at the end of a range session I had a mix of ammo left, 11 cartridges with 5 different loads ranging from 120 - 160gr, that I thought I would clean up. Took my time and let the barrel cool between rounds and managed a 2 1/4" group at 100yds. I basically shot everything into the same place. Now I also had a 358WIN that shot well but POI would change dramatically from one load to another. I had a 243WIN with straight grip that shot ok 1-2" three shot groups at 100yds. Some others that where about the same. And yes they all have poor triggers.
The 7mm-08 had a unique problem though. It would all of a sudden shoot 10 -12" high at 100yds when the weather got cool and damp. I could never solve the problem, thought it was a scope problem the 1st time, changed scopes 3x during my trials with it. Bases where checked for tightness, removed and re-installed with loctite as they where originally. Rings where lapped, etc, etc. I think it had to do with the connection of the forearm to the barrel and receiver, the recessed hole for the disc under the barrel to set into when the forearm screw was off centre slightly, ( opened the hole up so it didn't bind when the forearm screw was tightened down) but still had the same problem. I sold it to someone with full disclosure of the problem. Now after many years of reflecting on the issue I believe I needed to remove a little from the rear of the forearm where it sets over the pin sticking out of the receiver. I think the the distance between the forearm screw hole and the rear of the forearm was slightly too long and when the wood swelled slightly in the damp cool weather it would put pressure on the barrel.