I too have a target gray SRH in 454. I have about 3000 rounds through it. At about 2500 was getting 4 out of 6 light strikes. I sent it into ruger and they ended up replacing most of the springs. Since I've had it back i get one out of about 50. Have not tried the longer firing pin but i also read that there may be issues with the transfer bar not getting completely out of the way which can cause light strikes. Please let us know if you find a solution.