I am working with a Swede M38 and trying to work up some accurate loads for it. I'm using 3 brands of 140 grain bullet, and two different powders, IMR 4831, and Varget. I had decent hunting accuracy with one type of bullet, and another that was really good for me. I had 4 holes touching each other at 100yds. I had 10 rounds of each bullet loaded over the same amount of powder, for a total of 60 rds. What is the first thing to start changing to tighten accuracy. I'm thinking powder, maybe in .25 grain increments. I'm new to rifle reloading, and want to keep this methodical. Thank you in advance for the help.