Which type of rifling is best?

Button rifling is well suited to mass-production methods with high output. Button rifling leaves a smooth, bright finish inside the barrel that need not be lapped. Button-rifled barrels are very accurate. Bore and groove dimensions are very consistent.

What is the number of grooves in 7.62 mm rifle?

The common rifling twist rate for this cartridge is 305 mm (1 in 12 in), 4 grooves, Ø lands = 7.62 mm, Ø grooves = 7.82 mm, land width = 4.47 mm. The primer type can be Berdan or Boxer Large Rifle.

What are the advantages of 5R rifling?

Additional benefits of 5R rifling The 5R style of rifling does help fight bullet failure. This is because of the gentler angle on the sides of the lands vs. conventional style of rifling. Conventional/standard type rifling the land basically meets the groove at a 90 degree corner.

How many grooves are in a barrel?

The number of lands and grooves may vary from one to 20 or more, depending on the preferences of the barrelmaker/customer. Most common are four, six or eight lands and grooves. Barrels with more than eight lands and grooves are sometimes called “multigroove” or “microgroove” types.

What are the 4 types of rifling?

The 4 most common types of rifling in modern manufacturing are, in no particular order – button rifling, single point cut rifling, broach rifling, and hammer forging.

Does straight rifling work?

It is a knuckle ball and has that amount of variation in flight so it is not as accurate a spiral rifling but it is more accurate than no rifling and has the added flexibility be being used to fire shot without disrupting the pattern the way spiral rifling does.

What is the effective range of 7.62 x39?

400 yards
7.62×39 ammo fires a 123 grain weight fmj bullet with a muzzle velocity of 2,350 fps for a combat effective range of 400 yards. With the popularity of the 7.62×39 on the rise, soft point (SP) hunting ammo has become more readily available for hunting whitetail and other medium sized game animals.

What is the difference between 7.62 NATO and 762×39?

A 7.62×51 M80 cartridge has a 147 grain bullet loaded to a muzzle velocity of 2,800 fps. This gives it a muzzle energy of 2,559 ft lbs. The 7.62×39 cartridge often has a 123 grain bullet loaded to a muzzle velocity of about 2,350 fps. This gives it a substantially lower muzzle energy of 1,508 ft lbs.

Is 5R rifling the best?

5R is an improvement over conventional rifling by changing the shape and configuration of the lands and grooves. Conventional rifling, while effective, can be improved upon in two ways. 1. Conventional rifling has sharp 90-degree corners from the top of the land to the bottom of the groove.

Does 5R rifling increase accuracy?

tl;dr: No. Any theoretical advantage of one rifling profile over another is lost in execution.

Does a dirty barrel affect accuracy?

This bore insists on a certain amount of buildup to group tightly. This is really quite unusual; copper fouling is the enemy of accuracy and for a rifle to shoot its best it has to have a clean bore, but there always seems to be an exception.

What is the difference between lands and grooves?

The “lands” are the raised parts inside the barrel, and the “grooves” are the recessed portion; known as ‘rifling’ these are cut into the bore of a barrel of a firearm during production to increase the accuracy of that firearm. These lands and grooves force the bullet to rotate as it travels along it.