What rate of twist ?

[FrankG]

Im in the process of gathering parts to build a long range rifle (I hope) . I am planning to use either a VZ24 or Browning( Commercial Mauser) action . The barrel , a 27" blank , Im stuck between a 1:9" and 1:10" twist . I will be using 180gr. - 200gr. bullets . This will be a 300 Win Mag chambering .

Has anyone here played with the 1:9" twist? With what results ?

[W.R.Buchanan]

Either will work, but the 1-9 will stabilize longer bullets better, and 180-200gr bullets qualify as longer.

Normally Garands and Springfields come with 1-10 barrels, and they will usually stabilize 150gr sized bullets real well and 168gr sized OK.

But I have a NM barrel on my Garand that is 1-9 and It WILL shoot 168 grain bullets like you can't believe, and it shoots the 150gr ones better too. I run the 150's at 2700 and the 168's when I load them at 2600.

I would go with the 1-9 for your gun because of the proposed bullets you are looking at, be they store bought Hi perf jacketed bullets or even cast ones.

The reason why is, you have to shoot the gun alot to become good with it. You can't shoot full house .300 Win Mag (factory level) loads enough to get good. So you'll shoot lower power loads for practice, which in turn will mean less RPM's at the muzzle. The 1-9 will result in better accuracy with reduced loads all the way up to your top end stuff. The 1-10 barrel would do better with the hot loads but not as good with the light stuff.

I have 3 regular loads for my .30-06's 200gr cast @ 1900 fps. 147/150gr surplus M2's at 2700fps, and 150 Barnes copper bullets at 2700fps for hunting in CA. I'm good to 300yds with the last one, and I won't shoot farther. I don't need anything more to feed those 3 guns, 2 bolts, and one Garand. All three loads work in the bolt guns and I don't shoot the cast in the Garand, although I probably could if I wanted the extra cleaning.

If you are really serious about the long range stuff and I will define "long range" as beyond 400 yards. Then bullts like Berger VLD's definately come into the picture. Bullets like that require a faster twist rate in the barrel to work right , and they are among the short list of bullets that have enough oomph to do anything productive at longer distances so they must be considered.

You might want to work backwards from the bullet to the load to the barrel. Bergers have the twist rate needed for any given bullet on the box, and the 190gr VLD's may need even a faster twist than 1-9 as they are down to 1-7 for .22cal 90gr bullets being shot in National Match which are just smaller versions of the .30 cal bullets.

There are several other issues to consider with this proposed rifle which will certainly enter to the list of variables. You defintely need to look at the whole picture before you jump off the cliff.

I'm sure others will have opinions on this subject too. But I doubt they will be far off from mine.

Randy

[Armorer]

+1 on the Berger VLD's! I absolutely love the 168 VLD hunting bullets for my .308 deer rifle. Varget or N550 can make dime size groups at 100 in my Stevens 200. Haven't gotten around to trying them in my PSS yet. I would imagine they would be phenominal in a serious long range rig.

my ¢2
Armorer

[FrankG]

Thanks for the input :-) This spring the local gun club will getting the 600 meter range in order with new covered shooting area too. From the scuttlebutt the longe range stuff will start this summer .
I have a 30-338 which still will put a nice cluster under 1" at 100 but the throat is starting to look a bit thin at ball seat .

I need a new shooter and this new game is as good of reason as any I guess. Something new to try out .

[DCM]

Take a look here http://castboolits.gunloads.com/showthread.php?t=107867

[W.R.Buchanan]

Frank: Our range at Ojai CA also has the 600 yard capability, we shoot N M, Silhoutte, and avariety of BR events. in fact we have the current world Record holder for 600 yard BR at our club.

I'd be thinking about a Savage 12 Palma in .308 for that kind of long range stuff as you could shoot it all day and stil be able to stand up. I thought you were looking to shoot meat at at long range. No need for target shooting to be a painful experience.

For target shooting it doesn't matter how fast the bullet gets there or how high it goes in the middle of the trip. It only matters that it ends up where you want it to.

I'd look seriously at the least painful method of accomplishing that end.

Randy

[FrankG]

WoW ! Thats just a little out of my meager reach :) I see it has a long 30" barrel with 1:13" twist .

Being a do it my self type I think I will try a 28" barrel with a 1:12" twist with the VZ24 Mauser seeing how the magnum power isnt needed nor the extra 30 grs of powder.

[waksupi]

Thanks for the input :-) This spring the local gun club will getting the 600 meter range in order with new covered shooting area too. From the scuttlebutt the longe range stuff will start this summer .
I have a 30-338 which still will put a nice cluster under 1" at 100 but the throat is starting to look a bit thin at ball seat .

I need a new shooter and this new game is as good of reason as any I guess. Something new to try out .

Frank, if the throat is getting worn, it is probably just about perfect for cast boolits.

[FrankG]

Hmmmmmmm.........never even thought about that in that case . May look for a 308 Norma load for a 200ish cast boolit . Volume is near identical with the 30-338.

[John Taylor]

Having shot the 300 at long range with a custom rifle with great success I thought I would add a few thoughts. Use as long a barrel as you can. Mine was 31" with a 1 in 14 twist. I was using sierra game king bullets of 180 grain pushing them to almost 3400 FPS. Gun was zeroed at 200 yards with a 16 power weaver target scope. It took 40 clicks on the scope to get 600 yard zero. I never put it on paper at 600 but it was a consistent winner at the dynamite shoot in Montana. I practiced on quart oil cans at 600 yards, after I zeroed in on the first one I could go down the line and hit every one.
A note on barrel length, some high capacity cases can get an extra 50FPS with each extra inch of barrel. Faster twist rates will eat up velocity. If a 1 in 14" will work then don't use a 1 in 10" as it takes some of the power to spin the bullet at the higher RPS. With a slower twist the velocity needs to be high to keep the bullet stable, this is where the longer barrel comes in handy.

[Larry Gibson]

FrankG

"Being a do it my self type I think I will try a 28" barrel with a 1:12" twist with the VZ24 Mauser seeing how the magnum power isnt needed nor the extra 30 grs of powder."

With that action and that length barrel with that twist I would suggest the '06 with a match chamber with a tight neck. It will do very nicely with 175/180 gr MKs to 14-1500 yards. If cast bullets are in the game then I'd also look at the 14" twist. As John mentions there is no sense using up energy to spin the bullet faster when it is not necessary.

Larry Gibson