what gr bullet for 1:9 twist 7mmstw

[mciver]

Hey guys, been working with my new 7STW I had built by Chris Matthews at LSR. Has a 1:9 twist and seems to shoot bullets in the 150gr range a little better than my 175 SMK's. Is this typical of this twist rate or should I do a little more work with seating depth on the heavier bullets? (let the games begin)

 

[mscott]

Re: what gr bullet for 1:9 twist 7mmstw

You should be able to run 175 with a 1-9 barrel. I'm doing fine with them in a 1-9.5 at about 2950 fps. Maybe try another powder (I'm happy with Rel 25), but very rifle is a little different. What are you using now and what velocities?

 

[RBros]

Re: what gr bullet for 1:9 twist 7mmstw

Give the 168 and 180 bergers a try....I run the 168's at 3340 out of my 7 STW...I haven't chrono'd the 180's yet, but it appears they are around the 3200 mark. Use H1000 and a Mag primer.

 

[Lburt]

Re: what gr bullet for 1:9 twist 7mmstw

I have .280, .280AI, 7x64 Brenneke, 7br, and 7mm Rem Mag all with 1:9 twist barrels and it is hard to tell which is best between 140 and 150 NBT. 168SMK should work but not in my rifles.

 

[mciver]

Re: what gr bullet for 1:9 twist 7mmstw

Ive been using H1000 for the 175 SMK's at about 3000fps. The 150s's are sitting on RL25 and are moving out at around 3450. The 175's were originally worked up in Wyoming and cut a ragged hole at 100..now i'm sitting at an inch when I shoot at home in Washington. Nothing else has changed...except a great deal of elevation...i'm guessing this is my issue.??