Thread: 243 twist rate

Hi all,
What's the best twist rate for a 243, shooting from 55 to 100 grain projectiles?
And does anyone know what twist rate a Brno zkk601 243 is?

Thanks!

@the creeper

Mate, that's a big weight difference!
The tikka I had was 10 twist and it loved 87 vmax and 95 bergers.

What's the intended use? Sounds like you want something for varmints but the ability to smash a deer?

The 1:9.25 we have here likes the 100gr projectiles. Sexy Savages.

You're BRNO will have a 1in 10 twist rate , that means ,generally, that it will shoot up to 100 gr flat base projectiles . For 100 gr boat tail and above you'll need a 1in 9 or faster depending on the projectile but a 1 in 8 will suit most of the heavier projectiles .

Originally Posted by SlimySquirrel

Mate, that's a big weight difference!
The tikka I had was 10 twist and it loved 87 vmax and 95 bergers.

What's the intended use? Sounds like you want something for varmints but the ability to smash a deer?

I'm thinking more towards a fallow rifle, maybe reds so needs to handle the heavier pills, but 55gr at or near 4000fps sounds like too much fun to miss out on.

Originally Posted by Cigar

I'm thinking more towards a fallow rifle, maybe reds so needs to handle the heavier pills, but 55gr at or near 4000fps sounds like too much fun to miss out on.

You still can shoot the 55 grain projectiles in the faster twists I shoot 70 grainers in my 1:8" 6mmBR , Remingtons have a 1:9.125" twist if you have a 1:10" try Speer 90 grain Hot Cor projectiles or Sierra
100 grain SPT Pro hunter both are hard to beat.

I used to shoot 75gn Vmax for long range hares and magpies in a A1 sako, no trouble out to 500m!

Thanks everyone for the info

Think of twist rate in terms of minimum, ie a bullet X needs 1-9 or faster. My old Mans ZKK 601 243 was 1-10. Shot the hornady 100gr SP boat tail very well. Stabilizing is about bullet length not weight or style. Poor accuracy with a particular bullet is often nothing to do with twist rate, though it sometimes gets the blame unjustly , just as a well stabilized bullet is no guarantee of accuracy.

Your rifle will like certain pills and dis like others. Only way to find out is test them in YOUR rifle.
People can give you advice and say these and those are awesome but the fact is in YOUR rifle they maybe just sheer crap (accuracy )I love the Fed powershoks 100gr. They work very well in my rifle and are awesome on dropping big reds. For fallow they do alot of damage so maybe not the best choice for you and of cause your rifle has to like them but they would be worth a go and see how they go as you have sheer knockdown power with those

I had a zkk in 243, scratchy trigger but fit and finish was very good, Hornady 87sp grain projectile was the go to for accuracy.

Hey Cigar
I’ve used 1:10” twist .243s for many years, a CZ same as yours (my first centrefire in the 80s), various CZs and Tikkas and now a Howa which is the best one yet. The one pill they all shot really well is the Sierra ProHunter 100gr (1540). Half MOA, reloaded in Lapua brass with AR 2209, 20” barrel. I run them at 2800fps out to 400m.

This pill puts down reds with ease, its a frangible bullet so very effective at spreading the message through the vitals. I don’t heart shoot, I go for the front lung / CNS shooter (autonomous plexus) drop ‘em on the spot shot, also the neck in certain circumstances. The Sierra has been probably the most reliable killer of the bullets I’ve tried. You won’t get an exit very often, all the energy is used in the chest cavity, I very very rarely get a runner that goes much past 10-20 yards, 9/10 drop on the spot.

I’ve put a few guys onto the ProHunters over the years, don’t think anyone has struggled with stability or accuracy. Well worth looking at.

Originally Posted by Flyblown

Hey Cigar
I’ve used 1:10” twist .243s for many years, a CZ same as yours (my first centrefire in the 80s), various CZs and Tikkas and now a Howa which is the best one yet. The one pill they all shot really well is the Sierra ProHunter 100gr (1540). Half MOA, reloaded in Lapua brass with AR 2209, 20” barrel. I run them at 2800fps out to 400m.

This pill puts down reds with ease, its a frangible bullet so very effective at spreading the message through the vitals. I don’t heart shoot, I go for the front lung / CNS shooter (autonomous plexus) drop ‘em on the spot shot, also the neck in certain circumstances. The Sierra has been probably the most reliable killer of the bullets I’ve tried. You won’t get an exit very often, all the energy is used in the chest cavity, I very very rarely get a runner that goes much past 10-20 yards, 9/10 drop on the spot.

I’ve put a few guys onto the ProHunters over the years, don’t think anyone has struggled with stability or accuracy. Well worth looking at.

I have a sample pack of the 1540s on the way, plus a few others in the 85/87 grain range. Plus brass and dies, and rifle and scope, so the mail lady will be busy!

Personally id use something a little heavyer than 55’s 75 will be a little slower yes but you’re probably using them for varmint shooting right with a 75 you’re Ballistics will be better
And with a 55 you’re barrel will wear at a pretty good rate