Barrel Twist

[madang55]

So,Hypothetically, if a .223 needs a 1:9 twist to stabilize the heavier projectiles, 60 grain and upwards....What does it do to a 40 grain projectile?
Is it worth it to even try using 40g in a 1:9 twist? Does this also apply to all calibers? Faster twist for heavier projectiles, but what about the lighter ones?

[bladeracer]

So,Hypothetically, if a .223 needs a 1:9 twist to stabilize the heavier projectiles, 60 grain and upwards....What does it do to a 40 grain projectile?
Is it worth it to even try using 40g in a 1:9 twist? Does this also apply to all calibers? Faster twist for heavier projectiles, but what about the lighter ones?

35gn NTX works just fine in my 8"-twist, alongside the 80gn ELDM.

Twist-rate stability is determined by bullet length, not its weight. Monolithic bullets for example are much longer than lead/copper bullets of the same weight. A heavier blunt-nosed bullet may stabilise whereas a lighter VLD or ELD probably won't.

It comes down to bullet construction and RPM.
RPM is derived directly from twist-rate and velocity. If you have a bullet that is disintegrating, back off the velocity until it's okay.
I use a .224" 52gn bullet swaged from .22LR brass in .223Rem. Over 3300fps they disintegrate, at 3000fps they're fine. The range in between is random, some survive, some don't.

[madang55]

Good stuff. That's probably why 40V-max in my 223 suck. Too short especially as they are a boat tail.

[bladeracer]

Good stuff. That's probably why 40V-max in my 223 suck. Too short especially as they are a boat tail.

How do you mean they suck? Not accurate? Have you tried reducing the velocity a little?

The 35gn NTX is a copper bullet and is .725" long.
The 40gn VMax is copper-jacketed lead with a poly tip and is .686" long. It should shoot just fine.

The 80gn ELDM is 1.180" long. Shoots well in my 8"-twist, don't know how it'd go in a 9"-twist, but the 77gn SMK at .994" should be good.

[madang55]

Just didn't work, huge groups at 100, where the 53 and 55 worked from the get go. And that was before I started working the loads up. No problem really, I might look for 35 NTX and see how they go.

[on_one_wheel]

It's been said that a twist that's theoretically "too fast" for a given weight can over stabilise the projectile.

It apparently causes the projectile to fly nose high therefore causing extra drag which messes with the BC.

It's not a problem most shooters would need to worry about unless your into long range.

[marksman]

although 80gr bergers shoot very accurately in my 1:8" twist 55gr vmax shoot nearly as well
when l rebarrel this one again it will still be 1:8" twist although l shoot a lot more 55gr bullets

[deye243]

Good stuff. That's probably why 40V-max in my 223 suck. Too short especially as they are a boat tail.

Try the nosler 40BT as they are a bit longer because of the solid base