FF is perfect for break-in with newly finished barrels.
I use (5)#1 & (5)#2 compound bullets with aftermarket barrels.
I use (10) of each #1-#5 as suggested with factory barrels.
TMS is for later use now & then.
About 6 months ago I sent them an email asking about using their bullets in a brand new barrel. This was the reply.
For your barrel you will want to use the TMS system. You will shoot 7 to 10 rounds of this through your barrel then clean good. As the Krieger 5r barrels are a high quality this should be enough to break in as well polish the barrel.