Rebarreling a 243 - rifling twist considerations

[Wapiti]

Hi all,
Wanted to pick some brains here. I am about to order a TSE barrel in 6mm, for a 243.
I believe the standard for the last 1000 years for most brands in this cal is 1-10" but I think this is a bit slow even for 90gn bullets. They might stabilise but back in the old days, 80gn was standard when 1-10" was standardised. But what I think and the reality might be two different things, it doesn't matter.

I'd like to be able to up the weight of projectiles and also play around with long copper bullets, the cartridge case itself is perfect for this and I might just look at an AI version too when I get the reamer. Cases everywhere, and cheap.
But I would like advice too, would a faster twist stuff up the ability to shoot the lighter bullets well? They really teach fawn-pecking crows turn back into their individual atoms, the huge open hollow-points stepping one-up on the 22-250 for feather clouds.
And no, I am never going to ever be interested the 6mm Creedmoor case. This "groundbreaking" must-have "new" cartridge has up to 5gns less capacity than the old .243 depending on case brand.

What do you reckon? 1-8" twist? 1-7"?

[deye243]

I absolutely love the 243 as I consider it the best varmint cartridge ever developed if I was building one would be a one in 12 to shred critters in the paddock but up where you are I do believe I would not entertain the idea of having a 243 unless it was a one in eight i also like knocking off stuff at the longer Ranges than the average person but there are a lot of really good 100+ grain bullets on the market and also slightly lighter monolithics that need the extra twist just my waffle.

Now after all that I'll ask the proper question I should have asked at the start what are you using it for and what's your favourite projectile for the job

[Wapiti]

Thanks for that info mate, I also think the 243 is one of the best varmint cartridges, and it's also really flexible.

But I've been real interested in Outer Edge copper bullets in the 80 and 90 grain weights, they say for the 90's a 1-7" is best, there's the Hornady ELD-X Hunting 103gn, Bergers up to 120 etc. Does not work whatsoever in the twist in the Howa I have.
In fact that rifle is very fussy, HATES any powder except for 2208.
I use Atomic29 Aussie-made copper projectiles in a Sako .300 and it will one-hole 3 shots with 155 and 175gn projies, it's that performance that I'd like to see in the 243.

I also had a play with making copper bullets myself, but it's not economical in fact I never saved any costs with purchasing small batches of copper round bar. The main thing was, could I do it. Way less trouble than copper cups, swaging etc. but taking account of deflection was a learning curve, only took a few but means making only ones at a time is time consuming.

Anyway, primarily it's for dogs and any pigs I come across, I reckon the little Speers I've been playing with are a bit light in fact the barrel on this rifle LOVES them but just will not tolerate the 90 and 100 Hot Cors as far as a good group goes no matter what I do. Twist?
Yes I could grab one of our light accurate 308's for this which does everything here with absolutely no fuss but now I know the 243 can be improved, it's something I'd like to try.
Just wondering though whether or not a faster twist will destroy the possiblility of using 70-75gn bullets.

[deye243]

That's the thing with barrels sometimes you will have a barrel with a twist that will overspend a light projectile and it will Group dine sometimes it won't generally speaking though short bullets in fast twist barrels if they won't gfoup fast a lot of the time they will when you slow the load down a little bit since you've mentioned pigs and dogs I would just go the 1:8 or if you can find one and use your heavies you're 90 to 108 plus with 2209 should come up pretty good

[GQshayne]

I think you have described an issue with your rifle. This could potentially be rectified with a new barrel, in 1:10. The fact that it does not like 2209 is unusual, as is not being able to group 90gn projectiles. That is pretty standard fare for most .243 rifles.

[morerams]

The only reason to go with a faster twist than1 in 10 is if you want to use the long match bullets like the Sierra 107, or 110 HPBT or the Hornardy 108 ELD. 1 in 10 will handle anything else.