Barrel conture and its affect on accuracy ??

[James Jones]

I'm lookinging into getting a lighter weight barrel and was leaning toward the medium Palma conture only cut down to 24" , it's suposed to weigh in at 5.5lbs at 30" so I figure I have to at least loose a half pound by dropping 6" the question I have is do you guys think that this conture being lighter than say the Rem Varmint or the M24 will give up accuracy with a 3 shot group , I mean I'm sure it'll give up some but would one think it could open groups to the 3/4" from say a consistant cold barrel 1/2" gun
the caliber would be 308Win

 

[longtooth]

I have a barrel similar to what you're writing about and it shoots tighter then ½ inch groups. I had the barrel for some years on a Rem mod.7 action when it was 30 inches long. I took it off and cut it down to fit a Mauser 98 action and rechambered it to 308 Win. Recrowned her and had the whole set up cryoed. She shoots sub ½ inch groups even when hot. If the barrel is stress relived and chambered and crowned properly it should shoot well.

 

[Centre Punch]

Hi JD,
According to my calculations, your cut down Palma barrel will have the same muzzle diameter at 24", that the Remington Varmint contour has at 26" so yes you will lose a bit of weight. This also tells me that your barrel will be a little stiffer then the Remington barrel, simply because it is shorter. Theoretically, when fired your shorter barrel will produce a higher rate of barrel vibrations(harmonics)and thus shoot more accuratly.
If you want to shed a bit more weight, choose a cut rifled barrel of the same contour and have it flutted.

Ian.

 

[Mysticplayer]

Almost any barrel length can be made to shoot accurately, given enough support and proper load tuning. The key is in the rechambering.

If the chamber is cut cock eyed, that barrel will not shoot as well as it does now. If the chamber is cut better, accuracy will/could improve.

Barrel diameter also plays a small role in cold barrel accuracy. I shoot all types of rifles and barrels. In all cases, if the chamber is cut true to the bore, the bore has no damage and of good/better quality, acceptable crown, properly bedded action and concentric ammo tuned to the rifles wants, the rifle will shoot well.

The only difference with a small diameter barrel over a heavy barrel, is the likely hood of the barrel warping as it gets hot. This shows up as groups opening up.

For a hunting rifle where 1 to 3 shots is all that is usually needed, rarely an issue.

Jerry