No difference.
Eddy, give me a call . I have a new throat design that has been breaking records and makes every barrel last longer wit less pressure, more speed . give me a call at my custom shop, thanks Dave Kiff, ask for me if i don't answer , 1-541-826-5808-Have used several and seen no difference in longevity.
Eddy, give me a call . I have a new throat design that has been breaking records and makes every barrel last longer wit less pressure, more speed . give me a call at my custom shop, thanks Dave Kiff, ask for me if i don't answer , 1-541-826-5808-
Hal I figure if I have the time for the phone, than the person asking the Question does to . Right ? Call anytime and I guaranty i can cut your groups in half. thanks Dave KiffThat ought to make
That ought to make the phone ring.
Dave do you want to explain it a little here so you don't have to do it 100 time over the phone.
Its great your always thinking of new things.
Hal
What is the purpose of rachet rifling?
People ask for it, kinda like people asking for 5R.What is the purpose of rachet rifling?
Similar to purpose of R rifling. Reduced stress on the bullet jacket and easier cleaning.
No idea where you got that but it is not correct. The theory is that it provides somewhat better wind handling properties, plain and simple.
That's a theory. That theory is based upon increased bullet speeds. I would assume the increased speeds are due to less drag on the bullet jacket. If you read on Shilen website, 'easier cleaning' is plainly stated as a benefit to the ratchet rifling. It has always been a known benefit to 5R rifling as well. I have a Shilen SS ratchet rifle barrel and have owned 5R barrels in the past. I can assure you their wind handling capabilities are no different than standard rifled barrels. But the ratchet and 5R do in fact clean out much nicer and easier. So I'm not pulling this out of my ass. I actually have experience with those types of rifling.
I am also currently using a 3 groove 20 cal barrel on a rifle to determine if the claimed 20% longer barrel life is true. Tho it will be hard to match the shooting conditions of my past 6 groove 20 Cal barrels to draw a definite conclusion.
I'd be most interested to learn exactly how the type of rifling has anything whatsoever to do with bullet speed.
Easier cleaning would be what I'd call " marketing" and has nothing to due with how it came into being.
Study up on how all of these rifling patterns came back into favor, ratchet, 5R, 2 groove, octagon, MI, they all presume to impact wind and/or coriolus effect.
As to rifling patterns vs barrel longevity....don't get your hopes up, I have shot every configuration on the planet in benchrest rifles for a long time........it's got far more to do with the lot of steel than enything...how lucky do you feel?
Well Tim. Your the one who is partly wrong not Ledd Slinger. Ledd Slinger is correct about less stress on the jacket and easier to clean. Ratchet rifling is that the driven side of the land is of conventional shape with a sharp angle at the top and bottom, the opposite face curves into the top of the land and the bottom of the groove, and also the decent into the groove maybe sloped rather than perpendicular to the bore. The advantage of cleaning is there is lack of a sharp corner on one side of the grooves which means there is one less place for fouling to gather. 2nd, there is improved obduration which means less stress on the jacket because curves are easier for the jacket to conform to. Your right Tim about wind handling. In theory there is a significant lessening of a cross wind effect thought to come from the fact that the impression of the gently curved non driving side of the land ( which is a leading edge in relation to the bullet's spin) causes less "fin effect" from the rifling marks as the bullet spins while going at a tremendous rate while going to the target. It may be that this reduces the thickness of the air that is being disturbed around the bullet as it spins, shrinking the effective area that a cross wind can push on. The lessening of applied force should also result in less of the gyroscopic precession effect that causes a bullet to rise or fall in a pure side wind.No idea where you got that but it is not correct. The theory is that it provides somewhat better wind handling properties, plain and simple.
Well Tim. Your the one who is partly wrong not Ledd Slinger. Ledd Slinger is correct about less stress on the jacket and easier to clean. Ratchet rifling is that the driven side of the land is of conventional shape with a sharp angle at the top and bottom, the opposite face curves into the top of the land and the bottom of the groove, and also the decent into the groove maybe sloped rather than perpendicular to the bore. The advantage of cleaning is there is lack of a sharp corner on one side of the grooves which means there is one less place for fouling to gather. 2nd, there is improved obduration which means less stress on the jacket because curves are easier for the jacket to conform to. Your right Tim about wind handling. In theory there is a significant lessening of a cross wind effect thought to come from the fact that the impression of the gently curved non driving side of the land ( which is a leading edge in relation to the bullet's spin) causes less "fin effect" from the rifling marks as the bullet spins while going at a tremendous rate while going to the target. It may be that this reduces the thickness of the air that is being disturbed around the bullet as it spins, shrinking the effective area that a cross wind can push on. The lessening of applied force should also result in less of the gyroscopic precession effect that causes a bullet to rise or fall in a pure side wind.