Are more or less barrel grooves in a barrel more accurate?

I have a two .32 RKS Ron Smith gain twist barrels where the only difference is one has 8 grooves and the other has 6 grooves. Both shoot very well.

Hard to tell if one is better than the other. So I thought I would determine the difference between the two using the same powder load and bullet and assess their bullet velocities. Both were breech seated so the base band was engraved by the rifling.

The eight groove shot 25 FPS slower than the six groove and the eight groove had a standard deviation of 10 FPS whereas the six groove had a standard deviation of 5 FPS. Based on muzzle velocity maybe the six groove may have a slight edge.

Does anyone have additional information on the accuarcy of barrels based on the number of rifle grooves?

I find it very hard to believe that the number of grooves in a barrel will cause a bullet to behave differently in the wind.

Modern barrel making has equipment so much better than long ago, so this is not likely to be as important; but when cutting with one tooth, having an odd # of grooves put the support opposite the one cutter to at least two places (3 groove) where with only two grooves (or 4) with one tooth cutting it isn't supported as well (hence wanders a little). 

Now adays we have barrel straightening, normalizing, air-gauging and much more.

Just another tidbit - the brits firmly believe in having an odd no. of grooves, thus putting always a land opposite a groove - they claimed it minimized lead displacement, hence bullet deformation, which would give improved accuracy.  One of the few exceptions was Lancaster oval-bore (2-groove)

Jeff_Schultz wrote on Sep 8^th, 2009 at 8:51pm:


Really, why?Let me give you an example, not a laboratory example but pretty representitive of what we are trying to detect. Now we are going to be using 2 guns [benchrest guns] and we are giong to play "chase". This is a game where 2 guys using 2 guns try and shoot the same X on a target simultaneously and we do this on a fairly windy day. Now normally we are going to hold off for wind,etc to see who shoots better in challanging conditions but this time we are both going to hold center-x's and see what wind does to each barrel. One will be an 8-groove, one will be a 3 or 4 groove. We are shooting right twist bores and we are going to shoot in a hard left wind. That wind is going to push those slugs to the right and low and I would bet you a shiny new quarter that the slugs from the 8-groover are going to drop substantially lower than the other barrels. Go try it.

"I do know a cut rifled barrel can shoot darn good"

Numerous International Nationals have been won with Ron Smith's cut rifled gain twist barrels in Black Powder, Schuetzen, ISSA, ASSRA, and long range centerfire competitions. My best score with my .32 RKS was 1245/1250 with 45/50 centers at 200 yards and I took first on the bench with a .22 rimfire RKS at the ISSA Nationals this year. I don't like to just take the manufacturer's statement that he makes the best barrels; I prefer to review the records set by the best competitive shooters since I can't go out and test all the different barrels manufactured. Yes other manufactures make good barrels but others talk about cut rifle performance when they have never seen  properly cut rifled barrels that choke down and shoot exceptionally well. And the quality of the barrel is more about the exceptional skills of the machinist who knows how to properly cut rifle a barrel.

Bob, it all comes down to which pair of teeth you hold your tongue between when pulling the trigger!   

David Kaiser
Montezuma, IA

                                            
[/quote]
Joe, I never said anything about rifles being the same.
First of all, none of this is etched in stone, proven, etc., etc., but, let us take a standard right twist barrel.Shooting in a left wind your slug will drift right and down,no? In a right wind, that slug will drift left and up. So there is an element effecting our slug in two planes, horizontal and vertical. What about that slug gives us the vertical component of wind drift? Could the number of impressions, depth of them, and their particular configuration come into play? Quite a few shooters in quite a few precision rifle disciplines tend to believe they do. Play chase sometime. [/quote]

Tim, 
Playing chase with two rifles, two separate shooters in an uncontrolled environment is not what I would call proper "scientific control " .  I have played chase before. I have shot many rifles in bench matches and cant say one way or the other about wind drift effect on number of grooves. I do know that most lead bullet records were established with eight groove barrels. based on that I'd have to say the eight groove barrel is the least effected by the wind. Once again my opinion is not based on any test results obtained through proper " scientic control" but rather based on my observations. 
If I happen to be at a match where someone has a rifle with eight grooves, is shooting exactly the same bullet I am at exactly the same FPS I might, if I remember, shoot a game of chase. The chances of that happening are slim. Are we splitting hairs? I'm sure of that, but is fun to kick around. 

                                              Joe