69g smk in 22-250

I loaded up some 69grain Sierra matchkings i had laying around for my 22-250 with a 1-12 twist even though the box says 1-7 to 1-10 only.

I have put roughly 20 down range at about 3100fps and all are making nice round holes at 100 yds and are grouping pretty decent for a start out load.

Since they are stable at 100 would they remain that way on out to longer ranges? I haven't had a chance to stretch them out yet maybe in the next few days. I'm gonna try to get them a little bit faster and see if they still shoot as well and see if i can't shoot out to about 300 next time.

It's my understanding that if your good at 100 in most cases you'll be good farther out.

Basicly the rate you bullet is spinning doesn't slow down to fast, so it stays stable.

May be wrong, but that's my take on it.