<font color=red>[**censored**]</font> it DOESN'T, u dumb sob. there's
still BILLIONS of rds of 55 gr ball in National Guard armories. it makes no sense to use a 1 in 7 twist, and RUIN your ability to use that ammo, or all the milsurp stuff, or most of the sp's, etc. The 1 in 7 twist is WAY too fast for the 55 gr and lighter bullets.
The tracer material is a LOT lighter than a lead core, so bullets of the same wt are a LOT longer,and thus, require a much faster spin rate to be adequately stabilized. The tracer must weigh the same, have the same velocity, in order to "stay" with ball ammo. If the tracer's trajectory is not the same as that of the ball ammo, it's pretty worthless, dummy. We HAD a 55 gr tracer rd, the military discovered that it didn't stay with the newer, 62 gr ball rd, and they had to switch to the 1 in 7 twist rate.