7mm decisions

[kevins750]

So I picked up a shilen match blank in 7mm with 1-9 twist.
My issue's are:

Brass availability....7saum 7wsm 7prc is there any around?

The barrel can be spun on Howa SA .308 bolt face or 700 LA magnum bolt face.

Can a .284 with 180gr be done on a SA?

These will be 1K yd F-class type single fed rifles.

[kcstott]

a 284 with any kind of VLD bullet is not going to fit a SA if you want to eject a live round. that and a 1-9 twist is not the best for a VLD 7mm 180 grain.
but thats if you are going to use VLD bullets.

[kevins750]

Well crap....168vld just doesn't have that sex appeal.

Maybe 180 ELD?

[ar15barrels]

Well crap....168vld just doesn't have that sex appeal.

Maybe 180 ELD?

Hornady says 1:8 twist for the 7mm 180gr ELD.

https://www.hornady.com/bullets/rifle/7mm-.284-180-gr-eld-match#!/

[isntzen]

Hornady says 1:8 twist for the 7mm 180gr ELD.

https://www.hornady.com/bullets/rifl...r-eld-match#!/

No way a builder could go wrong accepting Hornady's assessment of an ideal twist rate for its own projectiles.

Still unless I'm mistaken, optimum projectile precision is obtained with a twist rate determined by a specific muzzle velocity, no?

What if the op has a 28" barrel and is hot loading 7wsm or say 28 nosler (not mentioned I know.) Is there some resource that can be used to determine if 1:9 twist is the optimum rate for 180 grainers at higher MV's?

[ar15barrels]

Still unless I'm mistaken, optimum projectile precision is obtained with a twist rate determined by a specific muzzle velocity, no?

What if the op has a 28" barrel and is hot loading 7wsm or say 28 nosler (not mentioned I know.) Is there some resource that can be used to determine if 1:9 twist is the optimum rate for 180 grainers at higher MV's?

Yes.
Given enough velocity be that either from barrel length or excess pressure, they could be made to work in a 1:9" twist.
Also the air density matters as much or more than the velocity.
If you shoot at 8000 to 10,000ft altitude, they would probably work in a 1:9 without an extra long barrel or pushing them hard.

[kevins750]

I have to stay under 180gr.

I have read "stories" of people pushing 180's and 190's through a 9tw. I had my mind set on 180's but barrel is a little slow.

26" barrel..

[ar15barrels]

I have to stay under 180gr.

I have read "stories" of people pushing 180's and 190's through a 9tw. I had my mind set on 180's but barrel is a little slow.

26" barrel..

Move to Denver, Colorado and it will probably work.

[divingin]

If you know your bullet specs and load performance parameters (or can guesstimate them) you can plug them in here:

https://bergerbullets.com/twist-rate-calculator/

[sigstroker]

So I picked up a shilen match blank in 7mm with 1-9 twist.
My issue's are:

Brass availability....7saum 7wsm 7prc is there any around?

You can at least count on Hornady to have 7 PRC available into the future for awhile.