Picked up some TB at the LGS this weekend and did some playing around with it. Saturday I tried it with some 158gr RNFP's, some Berry's 158gr plated FP's and some Berry's 158gr plated HP's. All backed by 4.5grs of TB. None exibited what I call good accuracy, 3-4" 10 shot strings for all loads at 25 yards.
Sunday I decided to just play around with the 158gr RNFPs and some different powder weights. Tried 3.2grs, 3.7, 4.2 and 4.7grs. Natural selection warning: the 4.5 and 4.7 loads are over book but I used IMR's formula and 5 grs will fit under these bullets without compression. Again nothing stellar in the accuracy dept but the 4.2 came in best at 2 - 5 shot strings around 2.5", slightly behind were the 4.7 loads. The 3.2 and 3.7 loads, forget about it.
About the only thing I determined was TB and the hardcast lead I was using sooted up the gun a fair amount. Nothing that didn't easily whipe off though.
