I bought a throat reamer for the Springfield, and did it myself. I got my OAL to 1.120 with the nukes, and 1.100 with the 147 Match winner FP\’s.
The Glock gen 5 I thought about reaming but it seemed to \”break in\” after 2000rds and I am able to seat longer now.
A KKM barrel my have a tighter chamber also due to them being more accurate barrels. Not sure though.
Sorry to answer so late.