243 rifle twist and bullet selection

[oz_lowrider]

I wanted to do some long range bunny busting with my PH 243 so I tried 55gn Nosler Ballistic Silvertips @ 3500ft/sec, and the slightest wind spoils a good group, they were all over the place. However, under the same conditions 80gn Sierra Spitzers did the job much better tight group and headless bunnies was the result. Twist unknown.

 

[oz_lowrider]

I found 55gn Nosler Silver Ballistic Tips in my PH would not puch any wind @ 3500ft/sec they were all over the place, even at 100yds. However, Sierra Spitzers solid base 80gn does the job under the same conditions. Twist unknown. I'm beginning to learn light bullets are not the way to go. Same results in mt 25-06.

 

[NCsmitty]

Rosco P, your pretty much maxed out with the Win 780 and I'm guessing you're getting maybe 2850fps. Your 20" barrel is not helping with the velocity and Sierra recommends a 1in8 twist or faster to stabilize the 107gr.
I'm not sure what twist Nosler recommends for the 105, but you're probably on the edge.
Perhaps if you try the new Rel-17 powder, you can gain a little velocity.



NCsmitty

 

[rangerruck]

... hmm bbl lenght shouldn't have anything to do with it, and the twist rate seems fine. At this point, we need some 243 handloaders to chime in on some different recipes, and possibly seating depths, brass recommends, etc., because so far, it seems like you should be better than that. Can we assume you have a pretty nice trigger, the bbl is either freefloated, pressure padded or it is bedded, and that you have a nicely done muzzle?

my 788 is a 1/10 twist, and loves the vld/softpoints by hsm ammunition, but in truth , it actually shoots the jacketed softpoints better than the vld's, which weigh 5 grains less.
The heaviest I am shooting through this is 105 grainers.
But then again, shooting is all subjective, and maybe your bbl, even though you would think a 1 /9 twist is allright, just simply ain't haven anything over 100 or 105 grainers... you never know.

 

[ms6852]

Your 1:10 twist will handle the lightest loads of 55gr. It may have a hard time handling loads of 100 gr or higher. Some rifles will handle the 100 gr others need a 1:9.25 twist. For the Heavier loads you will need a 1:7 to handle the 115 DTAC.

 

[Ky Larry]

I have a Savage Model 12BVSS in .243 Win. IB the twist rate is 1:9.25. Haven't got my instructional manual with me. It loves 55gr Sierra B.K.s and 58gr Hornady V-Maxs. It seems to like bullets undr 85gr best. Don't know if this is helpful or not. Also, I use one of the 4350 powders.

 

[paducahrider]

Fast Or Slow Twist?

Howdy!
I thought this argument was settled, decades ago, in 1955, when Remington came out with the .244 Remington cartridge, to counter the Winchester .243, but offered it with a slow twist (1 in 12)barrel. The slower twist just wouldn't stabilize heavier bullets, so the .244 was never offered with bullets heavier than 90 grains.
Remington corrected their mistake by offering a 1 to 9 twist barrel, which allowed bullet weights up to 100 grains, and renamed it the 6MM Remington.
That's the only real difference between the two cartridges/rifles.
Their conclusion was that smaller bullets will stabilize nicely with slower twists, but heavier ones will not.
I believe a little research would find that Mauser came to the same conclusion around the beginning of the twentieth (not twenty-first)century.
We just seem to keep trying to re-invent the wheel and re-learn the same, hard-won lessons.
Thanks for your time.

 

[rangerruck]

paducahrider; normally 99% of the time, I would agree with every word you just said-- that being said, we are talking about the 243 here. And just as there are ballistic anomalies that go on with the 22lr round, that happen with absolutely no other bullet, and that goes for other 22 cal bullets as well, there is a few strange things that happen with the 243/6mm bullets. I am not sure what it is, or even how to correctly describe what is happening, but for some reason, you will find a lot, A WHOLE LOT, of 243 shooters, with very good rifles, with 1/10 twist or faster, who when shooting light bullets all the way up to 80 grains, they group ... very .... mmeh, to say the least, then start throwing in anything from 85's up to 105's, which you would think is too heavy at the upper end, and suddenly they are a one hole punch.
If I were to take a stupid guess at this, I would say that the lands/grooves aren't being made correctly, for a 6mm bullet, that is traveling over 3000 fps from a bbl, and because of this and the molten action of a bullet during it's internal flight, there is a certain amount of slippage, or on and off traction, that the bullet is getting from the bbl. And that speed and grip inside the bbl, is not consistent because of this, so the lighter bullets get ' thrown around' a bit as they go down the tube, at differing speeds, causing weird accuracy or groupings downrange.
Then again, I may not have a clue to what i am talking about, and am just
totally full of it...