Thread: Barrel Twist rate needed for 175gr Hornady ELD-X

Hi there,
Been thinking of changing from the 162 gr A-Max to the 175gr Hornady ELD-X as it has a better BC than the 162's. My rifle is a Rem 700 with a 24 inch 1:9.25 barrel (factory)
Is it likely to stabilise the bullets OK, I have read also that stabilisation has a lot to do with the length of bullet as well and these are quite long.
Another question is am I going to get enough velocity out of the 24 inch barrel for long range work, I presume I would need at least 2900 fps to make it work OK.
I have 2217, and 2225 available.
Any thoughts?

Originally Posted by Mooseman

Hi there,
Been thinking of changing from the 162 gr A-Max to the 175gr Hornady ELD-X as it has a better BC than the 162's. My rifle is a Rem 700 with a 24 inch 1:9.25 barrel (factory)
Is it likely to stabilise the bullets OK, I have read also that stabilisation has a lot to do with the length of bullet as well and these are quite long.
Another question is am I going to get enough velocity out of the 24 inch barrel for long range work, I presume I would need at least 2900 fps to make it work OK.
I have 2217, and 2225 available.
Any thoughts?

What cartridge? I'm picking 7RM....

No good bro, need 1:8. Checked as i was keen too. Never know until you try though i guess

You will likely shoot it ok at a few hundred yards, but much further down range it will destabilise and turn to custard.
Stick with the 16x's mate.

The new 162 eld X are a good projectile, what are you shooting them out of?

I am still using the old A-Max out of my old 7mm Mag, maybe when the barrel is stuffed I will replace it with a 1: 8 twist and a bit longer. Been reading a lot on overseas forums and it gets a bit confusing with some saying no problem and others saying you need the 1;8 twist.
Thanks for the quick replies.

Lookup the Greenhill formula, lets you work out twist rate as long as you know the bullets length and diameter. (Weight dosnt matter)

Originally Posted by Mooseman

I am still using the old A-Max out of my old 7mm Mag, maybe when the barrel is stuffed I will replace it with a 1: 8 twist and a bit longer. Been reading a lot on overseas forums and it gets a bit confusing with some saying no problem and others saying you need the 1;8 twist.
Thanks for the quick replies.

And hitting gongs at 900 with old anaxs too dont forget

Originally Posted by Gibo

And hitting gongs at 900 with old anaxs too dont forget

Yeh true thought the 175's may work out further, you are right the 162's work well. We will see how much further we can ring out of the 7mm Mag / 162gr combo at the Toby Memorial Shoot shortly.

Originally Posted by Gibo

No good bro, need 1:8. Checked as i was keen too. Never know until you try though i guess

They say 1-8 for the 162 amax to don't they but they work well in my 9.5 ? I'm really interested to here of any one using them I'm might just bite bullet and give it a go but as above the 162 amax is mint so I'm sure the eld x will do the trick that extra 13 gns just has a bit of appeal

My 0.02$c,
As i read and "played" with Litz stabilisation thing on berger bullets website (Twist Rate Stability Calculator | Berger Bullets) you will see that you can shoot the 175 from a 1:9.5" twist barrel, BUT, you will need to push(higher velocity) harder for it to work.
The thing you need to consider about a barrel with faster twist rate is if you shoot other lighters projectiles "it will be fine" but some more expert and experienced people will give you better advise that in some cases too much is not always good. My opinion if i was about to re-barrel my 7mm RM rifle i would go for a 1:8.5(extreme).

Have a look in the link above.

Cheers.

Mac

P.S.: I was shooting the 168gr Sierra match king from my rifle(7mm Rem Mag) and it was perfectly fine As i was pushing it over 3000ft/s.

Please analyse the data i use for a basic calculation for a 180gr berger hybrid out of a 1:9" barrel going at 2800ft/s, completely acceptable.

Originally Posted by zacko

They say 1-8 for the 162 amax to don't they but they work well in my 9.5 ? I'm really interested to here of any one using them I'm might just bite bullet and give it a go but as above the 162 amax is mint so I'm sure the eld x will do the trick that extra 13 gns just has a bit of appeal

@puku is testing some for us now in his 7-300wsm but he has a 1:8 twist.

Originally Posted by Gibo

@puku is testing some for us now in his 7-300wsm but he has a 1:8 twist.

Jeez do you want me to get on with it do ya? I might get at it this weekend. Although I did bulldoze my range for a set of yards.

Sent from my SM-G900F using Tapatalk

Originally Posted by Gibo

@puku is testing some for us now in his 7-300wsm but he has a 1:8 twist.

Hahaha! You "crack" me up laughing @Gibo. The 1:8" twist will do just fine, the deal is with the slower twist such the 1:9.5" normally found in comercial rifles.

Keep us posted @puku.

Originally Posted by PERRISCICABA

Hahaha! You "crack" me up laughing @Gibo. The 1:8" twist will do just fine, the deal is with the slower twist such the 1:9.5" normally found in comercial rifles.

Keep us posted @puku.

Sweet so you test the 9+ twist