Barrel Grooves

[EOD Diver]

Guys,
I know that cut vs. button rifled and favorite barrel manufacturers has been beat to death already, but I thought I'd get your opinions on groove count. Scotty, I know Gary Schneider's M40 barrels have 6 grooves, are stupid accurate, and somehow still manage to shoot even after the throat has burned out. Right now, 5R seems to be the hot ticket with folks touting that each land/groove is offset and somehow deforms the bullet less while getting better purchase on its way down the barrel. Some think that the canted/trapezoidal rifling reduces fouling. Three groove barrels seem a lot like 5R in that each land/groove is offset, but with more surface area due to the reduction from 5 to 3. I've heard some consider them more resistant to erosion due to the increased surface area. It seems pretty contrary to 6 grooves though. I think that three groove barrels usually have traditional rifling unlike the canted/trapezoidal found in Boot's 5R style. Does fouling go down with land groove count? Would a canted/trapezoidal three groove be the ultimate barrel? Just food for though and a question for all of you 20 pound heads out there.
Joe

 

[DrMike]

Three groove barrels were popularized by benchrest shooters. The purpose appears to have been that there appears to be less fouling. There is no consistent evidence that one count is more accurate than another--either can produce good to spectacular accuracy. For many people, the jury is still out on which count fouls less.

 

[Kodiak]

Many of the U.S. military 03 Springfields didn't have very many grooves, but they still seamed to shoot pretty dang fine for a mass-produced war-rifle.

 

[FOTIS]

Many of the U.S. military 03 Springfields didn't have very many grooves, but they still seamed to shoot pretty dang fine for a mass-produced war-rifle.

In my early days of reloading I worked on one which was converted to a 308 Norma. Very popular conversion in those days. Very accurate firearm!

 

[Guy Miner]

Joe - I've seen the groups you posted from your rifle... The fancy one...

Whatever it's got for lands & grooves, the results are TERRIFIC!

Guy

 

[EOD Diver]

Guy,
Thanks for the compliment. I actually haven't even checked the groove count on my PAC-NOR barreled Legacy and won't get the chance 'till I get home, but it sure seems to like those 200gr ABs! I'm hoping it'll like the new 190 ABLRs as much. Hope you're getting the chance to burn some 25-06 through that CDL and wear out some shoe leather this spring. Speaking of which, how's the weather in WA? I'm looking forward to getting back there soon.
Joe

 

[FOTIS]

:mrgreen: :mrgreen: :mrgreen: As long as she likes them and she is accurate I would not care how they did it!

 

[Guy Miner]

Joe - we're getting slammed with a big late-winter/early spring storm. Well, it seems to be pretty well faded away now, but wow - it dropped snow in Everett, and all the way up the west side of the Cascades.

My wife and I got a fun mix of sunshine and snow yesterday while we were up bouncing along in the Jeep, looking for elk. Mostly blue skies, cool temps, and a few snow flurries. The mountain passes though, got hit hard by more snow over the past few days.

Guy