115 gr 243 7 twist

[Tilb004]

Hi Guys and girls ,

New to forum and have owned a tikka 22-250 for a year or so , so not a experienced rifleman .
Started reloading about 6 months ago so have some idea how to work up a good load for my rifle .
Have purchased a 243 winchester xtr model 70 and presume it has a 10 twist in it.
I want to rebarrel it with a 7 twist to shot 107 to 115 grain projectiles .

I know there's a few pit falls like barrel life and long projectiles wont fit in mag etc .
I would like some advice on your experience or someone your know that has gone down this path.
Any probs they have had and positive they have had .

Have seen it done on youtube etc .
Want it to be the next step up from the 250 for bigger animals if need be , big roos , pigs etc

Any advice would be appreciated.

Have done a bit of research on this and cant find much stuff in australia only the states

Cheers
Tilb

[bladeracer]

Hi Guys and girls ,

New to forum and have owned a tikka 22-250 for a year or so , so not a experienced rifleman .
Started reloading about 6 months ago so have some idea how to work up a good load for my rifle .
Have purchased a 243 winchester xtr model 70 and presume it has a 10 twist in it.
I want to rebarrel it with a 7 twist to shot 107 to 115 grain projectiles .

I know there's a few pit falls like barrel life and long projectiles wont fit in mag etc .
I would like some advice on your experience or someone your know that has gone down this path.
Any probs they have had and positive they have had .

Have seen it done on youtube etc .
Want it to be the next step up from the 250 for bigger animals if need be , big roos , pigs etc

Any advice would be appreciated.

Have done a bit of research on this and cant find much stuff in australia only the states

Cheers
Tilb

Is the barrel completely shot out?
I would measure the twist rate and even try some heavier bullets to see if they stabilise.
As you aren't looking for long range, heavy blunt bullets might stabilise just fine.

[Blr243]

Only ever heard of 107 or 105 weight in the upper range of the 243 choices. Not heard of 115 before

[JimTom]

Mate the ADI website has data for the 115gn berg VLD with a 1:10 twist. To be honest mate I’d give your rifle a go before going to the effort and expense of a new barrel as Bladeracer has already suggested.

[bladeracer]

Mate the ADI website has data for the 115gn berg VLD with a 1:10 twist. To be honest mate I’d give your rifle a go before going to the effort and expense of a new barrel as Bladeracer has already suggested.

Ignore ADI's twist rates, they are not able to format a document to allow different twist rates so they only list the standard twist, which will not stabilise the Berger 115gn VLD, Berger doesn't even claim their 95gn VLD will stabilise in 10"-twist.
Sierra, Speer and Norma do 100gn bullets for 10"-twist barrels, there might be others over 100gn as well. Definitely won't be using VLD or ELD bullets over 100gn though.

[JimTom]

Roger

[SCJ429]

I have not used 115 grain Bergers but 105 and 108 Bergers from my 243. The barrel is a 1:8 Maddco 28 inches long and made excellent velocities. I used 2225 and got over 2000 rounds out of it before it went off. New barrel chambered in 243 AI.

What do you want to do with your rifle? If it is hunting, why do you want to shoot 115s?

[GQshayne]

87-90gn soft point cup and core projectiles in a .243 will handle pig pigs no worries. If you were shooting pigs 100kg and over consistently and never anything smaller, then I would use a 90gn projectile in a heavier construction, such as a Nosler Partition etc. On average size pigs these projectiles do not expand enough, but would be ok on big fellas if that was all you shot.

No need to go bigger in my experience. Dunno how many pigs I have shot with 85-90gn projectiles of average construction - lots. In terms of ballistics, 87-90 is a good point to be at for the .243. Velocity is still high, giving good trajectory too.

Some of these other projectiles are designed for target shooting and are very good at that. But hunting is different to paper punching, and retained energy and expansion etc are more important.

[Blr243]

Last trip I used 87 vmax reloads in 243 and when I ran out I just used 90 gn ppu factory soft points. Never saw any difference on pigs. Only time I ever tried for big hard lead was for red deer 95 Barnes x. And 105 speers for thar in South Island n z

[Blr243]

Maybe the Berger 115 pill is offered to people with custom twist barrels like 6 mm competition? I don’t know. I tend to think of Berger’s as a target projectile rather than a hunting projectile

[SCJ429]

Berger do make a hunting 115 VLD and a separate target 115. For long range varmint shooting, I am not sure that you would do much better with a 115 over a 100 or even a 90 grain projectile. It may be better to move up to a 6.5 or a 7mm if you need a heavier bullet for hunting.

[GojiraSteve]

My worry would be that you'd over stabilise the lighter weight projectiles by running that fast a twist rate. If you only wanted to shoot 95gn+ projectiles then I suppose it makes sense. But if your baseline game animal is of a size requiring 95gn and above, and I were you, I think I'd be looking to rebarrel to a 6.5(something) rather than trying to make a 243 work at the limit of its capacity. (ironically while limiting its capacity at the lower end of the scale)

[bladeracer]

My worry would be that you'd over stabilise the lighter weight projectiles by running that fast a twist rate. If you only wanted to shoot 95gn+ projectiles then I suppose it makes sense. But if your baseline game animal is of a size requiring 95gn and above, and I were you, I think I'd be looking to rebarrel to a 6.5(something) rather than trying to make a 243 work at the limit of its capacity. (ironically while limiting its capacity at the lower end of the scale)

How do you over-stabilise a bullet, and why does it matter?
35gn NTX at 3900gn in my 8"-twist .223Rem is doing 350,000RPM without any accuracy problems.

[marksman]

seeing you are getting it re-barreled anyway have you considered the 6mm BR or my favorite the 6mm dasher
l hunt with a 6mm dasher using berger 105gr and sierra 100gr shooting to almost the same poi very fast and one ragged hole
the thing l like about them most is the load data is already there, before l picked up my dasher l knew what the load would be within 1 gr of powder
you would not be disappointed in either
https://www.6mmbr.com/gunweek009.html

the 6mm slr was made to shoot the 115gr bullets and is another good one but is not as easy to load for as it can be a bit finicky
http://6mmar.com/Super_LR.html

something to chew up a bit anyway

[GojiraSteve]

How do you over-stabilise a bullet, and why does it matter?
35gn NTX at 3900gn in my 8"-twist .223Rem is doing 350,000RPM without any accuracy problems.

"Over-stabilise" is perhaps a bit of a cockeyed way to describe the destabilising effect that too high a twist rate can have on a projectile, but you often hear the term used in reference to it.

Either way the phenomenon itself seems to be pretty well regarded as fact. While I don't have sufficient knowledge of physics to give you a breakdown there's any amount of published information only a google search away, from people way smarter than me.

As for circumstantial evidence, its not by accident that rifles chambered for stubby bullets all use relatively slow twist rates (think lever actions in pistol calibres, right up to 45/70s)

Projectiles which are long for weight (like the NTX line) do exist and can mitigate or eliminate the problem, so perhaps I should also have said "shorter" rather than "lighter" projectiles, and specified that my suggestion didn't apply if the OP was to run premium non-lead projectiles if he dipped below 90gn.

But none of that changes the core point, which is that building a hunting rifle which is so heavily geared to performance at the upper limit of a cartridge's design specs, makes less sense (to me) than incurring the same cost to rebarrel in a calibre where those projectile weights (assuming were talking about jacketed lead projectiles) sit closer to the middle of its normal performance spread.

[SCJ429]

You can over stabilise a bullet, that is to say you can increase the rpm to exceed the design limits of the bullet and the jacket comes apart. I was using 62 grain bullets and at speeds over 4000 fps the bullets did not hit the target. I am not sure of the exact speed because the chronograph could not see them. I assume they came apart as soon as they left the barrel.

A 1:8 twist barrel will shoot most bullets if you keep the speed at a reasonable level for lighter bullets.

As said earlier, it is easier to rebarrel in 6.5 Lapua, Winchester, Swede or Creedmoor and shoot 140 grains.

I second your idea of a 6mmBR there MM. I have a straight BR as a hunting rifle and have taken goats and pigs with it.

[duncan61]

I completely understand where you are going with this line of thinking Tilb004.I have done it myself and over the years watched many others.When I loaded shotgun I was obsessed with getting all this performance and you end up back to standard after learning that it does not help.Its a lot of fun at the time but you have asked for advice.I maintain if you feel you need a heavier bullet get a bigger chambering.The .243 will kill any pig in Australia with 80-90gn pills designed for hunting.The biggest pig I have ever seen on a ute was a big Ginger boar a pro shooter took with a .223 and a head shot in the Kimberlys It was hanging on the rack and its snout was nearly on the ground and was around 400 lb.We all underestimate the power of centrefire rifles I have worked with a property owners son who used a 22/250 and it can do a lot at a long way.I am not sure how big the pigs are where you are but I have dropped heaps at night with a neck shot from my .222 50gn doing about 2700fps.I have nearly 300 reloaded .243 and they are all 80gn projectile one of my team went the heavy bullet pathway and all he did was make a lot of noise and missed a lot.when we set up a target his bullets were spraying all over the place.All this rebarreling nonsense is for target shooters trying to clover leaf at long range The accuracy test for pro culling roos is 5 shots into an 80 mm circle at 100 metres and a standard .243 will do that out the box.Good luck with it its all good fun and I look forward to seeing which way you go

[Madang185]

Only experience is with 115gn Protector points form Brisbane bullet maker Gary Little in 243 Ackley, 1:7 Lilja barrel.

45gnsX AR 2225=2815f.p.s. and 0.62 inch 3 shot group
44gndX AR2213S=2845f.p.s. and 0.52 inch 3 shot groups.
Bi=oth still subject to further proof loads but look good

[No1Mk3]

My own experience, yours may differ,
25-06 117g SP, lethal on pigs, roos, fallow etc,
243 90g SP, read above,
22-250 60g, SP, see above,
225 Win, 60g SP see above. No pig too big, shot placement is King. All of the above small centrefires I own have performed very well on all medium game I have hunted here and overseas, so don't discount your 243 with 90g well constructed hunting projies, shoot a few and see then if you really want to re-barrel and can afford to do so for fun and excitement, jump in! But I would try a few heavy pills in your current rifle to see how they shoot before ringing a gunsmith, Cheers and good luck

[bladeracer]

I had the same with 52gn bullets swaged ftom .22LR brass, over 3000fps in my 8"-twist barrel they start coming apart, by 3300fps none of them reach the target at all. Keep them under about 300,000RPM. But that is an RPM issue, nothing to do with stability.

The 35gn NTX I've pushed almost to 4000fps with good accuracy, I haven't pushed the 35gn VMax as hard yet. I also have some 33gn, and I think some 30gn bullets I could try. 4000fps is well over 350,000RPM in my 8"-twist Ruger.

You can over stabilise a bullet, that is to say you can increase the rpm to exceed the design limits of the bullet and the jacket comes apart. I was using 62 grain bullets and at speeds over 4000 fps the bullets did not hit the target. I am not sure of the exact speed because the chronograph could not see them. I assume they came apart as soon as they left the barrel.

A 1:8 twist barrel will shoot most bullets if you keep the speed at a reasonable level for lighter bullets.

As said earlier, it is easier to rebarrel in 6.5 Lapua, Winchester, Swede or Creedmoor and shoot 140 grains.

I second your idea of a 6mmBR there MM. I have a straight BR as a hunting rifle and have taken goats and pigs with it.

[Tilb004]

Thanks guys for all your replies ,has given me a lot to think about .

Bladeracer , i dont believe the barrel is shot out , but bought the gun with not much history behind it.
Part of me just wants the chance to rebarrel for the experience of a custom barrel.haha.
I should really see what heavy pill it likes first , that would be the sensible thing to do.

SCJ429,Just want it for hunting reason mate , seen a few vid's on the 115 and looked impressive .
No real justifiable reason for it .
Sounds like your maddco 8 twist handles the heavy bullets well, might have to look a an 8 twist krieger .
How do you find the 28 " barrel for hunting , i was thinking around the 24 to 26".

Gqshayne , Thanks for reply ,will take you advice on board.

BLR243 , Thanks for advice i heard those barnes do a fair bit of damage , some thing else for me to think about .

Gojirasteve Think you could be right , might be asking a bit to much of the 243.

Marksman , I have read some articles on the 6 mm dasher and they do seem impressive .
Do you have to order a 6mm dasher barrel or do they machine the throat of an existing barrel .
What about the brass ? is it easy to get your hands on .
You"ve got the juices flowing at the prospect of one .
What twist is your dasher .

Thanks once again for all the replies , it's forums like this that give so much knowledge to newbies like me .

[marksman]

my 6mm dasher barrel is a shilen match grade 8" twist in #6 contour, you just order a barrel and the smith will chamber and fit it, you can get your existing barrel rechambered if its not to far gone. norma are making the dasher cases now so for those who dont want to form cases that is the go, they do have a longer neck
l form my own cases from lapua 6mm BR cases its easy to do l just put a lighter load with my bullet into the land and go bunny shooting at longer distances
the dasher is still the most popular light gun cartridge and still holds a world 10-shot heavy gun record
they are very addictive, dies are available
the left is a 6mm BR case then the formed lapua 6mm dasher and the right is the 6mm dasher norma case



it would be easier to have a Br done with no forming

my 6mm dasher

[SCJ429]

If you want to rebarrel your rifle you will need to find yourself a smith, he can order your barrel blank in the profile and twist rate you want. He will chamber the rifle using a reamer and thread it to suit your action. This is going to cost you $1,000.

I don't use my 28 inch barrel for hunting. I think 24 or 26 would be plenty for a hunting rifle. You can chamber your current rifle in any case that uses a 308 headstamp. Something easier than a 6mmBR or Dasher would be a 6mm Creedmoor, 6XC or a 6x47 Lapua. They won't shoot much better than the 243 but may appeal to you more.

[SCJ429]

Sorry Marksman has said most of this stuff as I was typing.

[SCJ429]

Here is a Sako with a Hardy barrel, all the hard work is done for you by an awesome gunsmith.

https://www.usedguns.com.au/Product.aspx?p=166523

[Tilb004]

I completely understand where you are going with this line of thinking Tilb004.I have done it myself and over the years watched many others.When I loaded shotgun I was obsessed with getting all this performance and you end up back to standard after learning that it does not help.Its a lot of fun at the time but you have asked for advice.I maintain if you feel you need a heavier bullet get a bigger chambering.The .243 will kill any pig in Australia with 80-90gn pills designed for hunting.The biggest pig I have ever seen on a ute was a big Ginger boar a pro shooter took with a .223 and a head shot in the Kimberlys It was hanging on the rack and its snout was nearly on the ground and was around 400 lb.We all underestimate the power of centrefire rifles I have worked with a property owners son who used a 22/250 and it can do a lot at a long way.I am not sure how big the pigs are where you are but I have dropped heaps at night with a neck shot from my .222 50gn doing about 2700fps.I have nearly 300 reloaded .243 and they are all 80gn projectile one of my team went the heavy bullet pathway and all he did was make a lot of noise and missed a lot.when we set up a target his bullets were spraying all over the place.All this rebarreling nonsense is for target shooters trying to clover leaf at long range The accuracy test for pro culling roos is 5 shots into an 80 mm circle at 100 metres and a standard .243 will do that out the box.Good luck with it its all good fun and I look forward to seeing which way you go

dunca61Thanks for response and i understand where your coming from. Will probable end up exactly where you say , back at the start .
I am new to the shooting world and there is so much info out there and can be confusing .
I think i will end up keeping the original barrel to see what it ends up like , rebarreling is always an option .
There has been some great info on different bullets being used and realistically up to 100 gr projectile will do me .
Any way i will let you guys know .
Cheer mate
Tilb

[GQshayne]

I will re-iterate one of my points and expand on it a bit, and that is the .243 works well with 80-90 projectiles, not only for expansion etc on game, but also with trajectory. With projectiles in that class, you can run above 3000fps at the muzzle. I like to keep my velocity at a reasonable level without being near maximum, as this helps with max point blank range, and lead required on running targets. So with 90 grain projectiles, and a moderate load of AR2209, muzzle velocity is about 300fps, which is good for trajectory, and you are not burning out barrels trying to get the same velocity out of bigger projectiles.

Perhaps, as others have suggested, if you want to run larger weights, you could increase the size, to perhaps 7mm/08 as an example. But that would be another discussion.

[SCJ429]

You are running your 243 very mild there, my little 6mm BR can shoot a 90 grain projectile at 3000 fps. I shoot a 105 projectile out of my 243 at more than 3,300 fps and get good barrel and brass life.

[duncan61]

I am using 35gn of ADI 2208 as I have a few kilos of it left and am getting 3000fps plus with 80 gn PSP and am very happy with the recoil and muzzle flash and terminal effect.I am going south Monday to do grouping and a bit of hunting with a fellow enough gun shooter and will post some pictures.I am interested in the load that gives 3300 with 105 pills thats the same as my 7mm Rem Mag ballistics

[SCJ429]

I used 2217 and the speed was 3,255 fps. I also tried 2213 but only pushed it to 3132 fps. It had more in it but I never went back to see how far.