Any other rifles use 2-groove rifling like 1903? I know it is adopted to speed up production and the grooves are not as deep as other military rifles, but seems like accuracy and barrel life are not degraded much. I don't think 2-groove rifling is "popular", but why not if is easier to produce and perform well?
2-groove rifling
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ColtPythonElite
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I have seen Benchmark two groove barrels on .22 benchrest rifles.
rcmodel
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I don't know.
I just think people would dismiss any manufacture who would stoop so low as to try to sell them on it today.
I do know the 2-groove 03A3 sporter I built in 1962 will shoot under 1 MOA with handloads.
And could still be doing it 100 years from now given proper care & cleaning.
I sure have nothing bad to say about them.
rc
I just think people would dismiss any manufacture who would stoop so low as to try to sell them on it today.
I do know the 2-groove 03A3 sporter I built in 1962 will shoot under 1 MOA with handloads.
And could still be doing it 100 years from now given proper care & cleaning.
I sure have nothing bad to say about them.
rc
The question I've always asked, but never had the answer was; why is 6 grooves the standard?
There is 5R, which are just as accurate.
Some high end barrel makers that use single point cut rifling will use a 4 groove rifling too.
How did we get to 6 when 2 or 4 or even 5 seemed sufficient?
There is 5R, which are just as accurate.
Some high end barrel makers that use single point cut rifling will use a 4 groove rifling too.
How did we get to 6 when 2 or 4 or even 5 seemed sufficient?
Simon_Edmondson
Member
There is an interesting article somewhere on the interwebs that documents research by IIRC Remington into the service life, accuracy etc of a 2 groove vs a conventional Enfield 5 groove. Long story short, they found no real advantage with the 5 groove for that particular application (Wartime bolt guns)
Edited:
Found it. http://www.remingtonsociety.com/rsa/journals/two-groove
Edited:
Found it. http://www.remingtonsociety.com/rsa/journals/two-groove
az_imuth
Member
I always felt that the 4 groove was the standard. On some older Winchester .22 rifles, you had to upgrade in order to get a 6 groove barrel. their standard .22 barrel was 4 groove. Maybe it was different with other manufacturers.
As to the OP's question, I've never heard any complaints about the 03-A3 2 groove barrels. I have no firsthand experience with them since my Remington 03-A3 came with a Remington 4 groove barrel dated 4/43.
james layman
Member
NRA used to put out two publications on cast bullets. They are no longer available. They advise a longer bullet will do better, such as a 220 gr cast bullet in a two groove barrel. Jim
Detritus
Member
some of the WW2 era No.4 Enfields also had 2-groove rifling, At least some of the Lend-Lease Savage made ones.
Had a Savage made No.4 Mk1* with a two groove barrel.
Sold it due to not being able to get on a 4x4 foot sheet of paper with hand-loads, though that I believe was due throat damage. the first 1/2-3/4" of the left "Land" looked like a rock strewn road, rest of the rifling was sharp and bright.
I read the article, it is interesting that it says the 2-groove rifling has same groove and land diameters as the 4 groove but the rifling sure looks like shallow when compares to mausers or modern rifles. When I first saw the 2 groove rifling on 1903 barrels, actually 1912 Chilean mausers that converted to 308 with 1903 barrels, I thought the bores are worn.
DougW
Member
Savage and Long Branch #4mk1* had 2 grooves barrels, but could also have 4, 5, or 6 groove barrels. Fazakerley, BSA, and Maltby usually have 5 groove, but some British built rifles may have received 2 groove during FTR with barrels from Savage or Long Branch. 2 of my 4 Savage built #4's have 2 groove, the other 5 groove.
Curator
Member
When a bullet enters the rifling, the lands displace metal from the bullet sides and the slug obturates slightly. This may make the bullet both fatter and longer (slightly) This distortion can lead to and unbalanced projectile not revolving around its center of mass and degraded long-range accuracy. Not all bullets will deform uniformly. Harry Pope made his record-winning barrels with 12 shallow lands and grooves with equal width. This was the reasoning for Marlin's "Micro-groove" rifling. The more equally (and less) bullet metal is displaced the more likely the bullet will remain stable at high RPM created by the rifling. Think about a tire out of balance on your car at 80 MPH! A bullet from a .308 Winchester with 1 in 12" rifling twist is spinning at 180,000 RPM.
ColtPythonElite
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So Curator, what are you trying to say regarding two groove barrels?
maybe post 8?
Swampman
Old Fart
The earliest "production" two groove rifle of which I'm aware was the muzzleloading British Brunswick rifle of 1836.
It had a two groove barrel designed to take a special round ball with a "belt" cast around it's circumference sort of like the rings around Saturn. When loading, the belt had to be carefully fitted into the grooves of the barrel before the ball was rammed home (see the thumbnail at the bottom, this is one case where a picture is worth more than a thousand words. The top illustration is of the barrel and the bottom is the belted ball).
It was fairly accurate in its day, but the invention of the higher BC, more accurate, expanding base Minie' ball made it obsolescent fairly quickly. Despite that, production continued for over 50 years. It was even used by some Confederate troops during the War of Northern Aggression.
The British revived the two groove concept again in 1941 in an effort to speed up rifle production during WWII. They did extensive testing which showed no substantive differences in either accuracy or barrel life between their standard 5 groove rifling and the new 2 groove version, so it was accepted (but not required) as an alternative form of rifling for all .303 rifles.
After the US joined the war, US Army Ordinance "borrowed" the British research on two groove barrels. Unfortunately, in a mistaken effort to speed up production, the US Ordies REQUIRED two groove barrels. High Standard, who were producing all the barrels for Smith Corona '03's at the time, was using the new, faster "broach cut" (also called button rifling) method to rifle it's barrels rather than the older, slower to produce, cut rifling used by Remington.
Since High Standard had already designed, tested and produced four groove broaches and was using them successfully, they told the Army that the switch to two groove rifling would actually slow production and increase costs, since they'd have to design, test and produce all new two groove broaches before they could continue barrel production.
Back in those days there was a real war on and apparently US military procurement had not yet developed it's current penchant for sloth, procrastination and delay.
Rather than invoking a penalty clause and fining High Standard for failure to fulfill its contract, the Ordies simply rewrote the contracts and specs so that two groove barrels were required only where it would result in cost and/or time savings.
Regardless of the fact that tests showed production two groove barrels to be fully as accurate and long lasting as four groove types, there has always been a certain amount of prejudice against two groove barrels in this country, probably because people see them only as a cheap, second rate wartime expedient.
The truth is that the cut two groove barrels were actually more expensive and required much more time and skilled labor to produce than the button rifled four groove types.
An unfortunate result of the aversion to two groove barrels is that in the past, certain companies bought up the cheaper two groove barrels, cut two extra grooves in them, and sold them to unsuspecting buyers as original four groove barrels.
If you look at the altered barrels through a bore scope you can usually spot them fairly easily.
If they've been altered the finish in the "added" grooves is usually somewhat different from that of the originals. There may also be variations in the width of grooves or lands. Although USGI two groove barrels will usually shoot just as well as USGI four groove barrels, the "converted" four groove barrels are a total crap shoot because they never had to pass a USGI armorers inspection after the second set of grooves was cut. The altered barrels will usually have the acceptance stamp on them, but it was put there when they were two groove barrels.
Caveat Emptor!
It had a two groove barrel designed to take a special round ball with a "belt" cast around it's circumference sort of like the rings around Saturn. When loading, the belt had to be carefully fitted into the grooves of the barrel before the ball was rammed home (see the thumbnail at the bottom, this is one case where a picture is worth more than a thousand words. The top illustration is of the barrel and the bottom is the belted ball).
It was fairly accurate in its day, but the invention of the higher BC, more accurate, expanding base Minie' ball made it obsolescent fairly quickly. Despite that, production continued for over 50 years. It was even used by some Confederate troops during the War of Northern Aggression.
The British revived the two groove concept again in 1941 in an effort to speed up rifle production during WWII. They did extensive testing which showed no substantive differences in either accuracy or barrel life between their standard 5 groove rifling and the new 2 groove version, so it was accepted (but not required) as an alternative form of rifling for all .303 rifles.
After the US joined the war, US Army Ordinance "borrowed" the British research on two groove barrels. Unfortunately, in a mistaken effort to speed up production, the US Ordies REQUIRED two groove barrels. High Standard, who were producing all the barrels for Smith Corona '03's at the time, was using the new, faster "broach cut" (also called button rifling) method to rifle it's barrels rather than the older, slower to produce, cut rifling used by Remington.
Since High Standard had already designed, tested and produced four groove broaches and was using them successfully, they told the Army that the switch to two groove rifling would actually slow production and increase costs, since they'd have to design, test and produce all new two groove broaches before they could continue barrel production.
Back in those days there was a real war on and apparently US military procurement had not yet developed it's current penchant for sloth, procrastination and delay.
Rather than invoking a penalty clause and fining High Standard for failure to fulfill its contract, the Ordies simply rewrote the contracts and specs so that two groove barrels were required only where it would result in cost and/or time savings.
Regardless of the fact that tests showed production two groove barrels to be fully as accurate and long lasting as four groove types, there has always been a certain amount of prejudice against two groove barrels in this country, probably because people see them only as a cheap, second rate wartime expedient.
The truth is that the cut two groove barrels were actually more expensive and required much more time and skilled labor to produce than the button rifled four groove types.
An unfortunate result of the aversion to two groove barrels is that in the past, certain companies bought up the cheaper two groove barrels, cut two extra grooves in them, and sold them to unsuspecting buyers as original four groove barrels.
If you look at the altered barrels through a bore scope you can usually spot them fairly easily.
If they've been altered the finish in the "added" grooves is usually somewhat different from that of the originals. There may also be variations in the width of grooves or lands. Although USGI two groove barrels will usually shoot just as well as USGI four groove barrels, the "converted" four groove barrels are a total crap shoot because they never had to pass a USGI armorers inspection after the second set of grooves was cut. The altered barrels will usually have the acceptance stamp on them, but it was put there when they were two groove barrels.
Caveat Emptor!
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Edarnold
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Point of information regarding broached versus button-rifled barrels. A broached barrel is cut-rifled: the difference from 'conventional' single-point cut-rifling is that the broach cuts ALL the grooves at once, rather than one at a time, and usually in a single pass. Think of a bore-diameter plug with groove-width files sticking out to cut the grooves, and you have a rough idea of how it works ( though there is more to it if you want a smooth finish). Broached barrels can be good quality if the the broaches are carefully made and maintained, but getting a smooth finish means watching the finished barrels carefully for defects, and replacing the broach if there is any sign of imperfections.
Button-rifling is completely different: the tool is the reverse of the desired bore dimensions, and is pulled or pushed through the finish reamed barrel, displacing the the metal from the grooves rather than removing it. Done properly, the button-rifled barrel will have a very smooth finish compared with any but the most carefully cut-rifled barrels. Button-rifling also allows the use of stainless-steel alloys, which generally have miserable cutting properties. The downside to button-rifling is the strain created in the barrel by displacing the metal from the grooves, which means for best results the finished barrel has to be heat-treated for stress relief.
Button-rifling is completely different: the tool is the reverse of the desired bore dimensions, and is pulled or pushed through the finish reamed barrel, displacing the the metal from the grooves rather than removing it. Done properly, the button-rifled barrel will have a very smooth finish compared with any but the most carefully cut-rifled barrels. Button-rifling also allows the use of stainless-steel alloys, which generally have miserable cutting properties. The downside to button-rifling is the strain created in the barrel by displacing the metal from the grooves, which means for best results the finished barrel has to be heat-treated for stress relief.
Curator
Member
Bullet design and construction can and does affect accuracy with 2-groove barrels. US '03-A3 2-groove barrels seem to work pretty well with a 5/8 land to groove ratio especially with cast bullets. In fact, some of the Cast Bullet Association shooters prefer the Springfield 2-groove over others. Having shot the .30 caliber "high-power" circuit in the late 50s and 60s, no one was using a 2-groove Springfield that placed in the top quarter. That is not to say one can't find a load that they shoot well. My '03A3 2-groove shoots M1 ball very well but not M2 ball ammo.
The Lee Enfield 2-groove barrels with 4/5 land to groove ratio have their own issues and are notoriously inaccurate with some boat-tail bullets. Enfield enthusiasts are able to get these 2-groovers to shoot well with careful bullet selection usually after a lot of experimentation. These barrels cause considerable bullet deformation as the .311 diameter slug is forced into the .303 diameter bore. Not all bullets deform uniformly creating accuracy problems.
In all three of my Lee Enfield 2-groove rifles, the .311/180 Sierra Match King bullet shoots awful, often key-holing. Yet the .310/180 Remington "CoreLok" round nose is quite accurate. Both bullets shoot much more accurately in my 6-groove CNo.4Mk1* with almost no load development. I credit this to the more uniform (and minimal) bullet deformation provided by the 6-groove rifling.
HEAVY METAL 1
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My Remington 1917 has a WWII era 2 groove barrel that is very accurate. It is accurate with flatbased bullets only. BT bullets are not accurate at all. YMMV.
win71
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interesting thread
I've often wondered why is there what there is! 2 groove, 4 groove, 6 groove, why no 3 groove or 5 or 7. Things like this don't just happen. Then there is the odd man Marlin Micro Groove. It's hard to even count how many grooves they used.
What do the high grade target barrel makers use?? There has to be a reason for that too.......Anybody know?
I've often wondered why is there what there is! 2 groove, 4 groove, 6 groove, why no 3 groove or 5 or 7. Things like this don't just happen. Then there is the odd man Marlin Micro Groove. It's hard to even count how many grooves they used.
What do the high grade target barrel makers use?? There has to be a reason for that too.......Anybody know?
dprice3844444
member
probably has to do with designing the cutter
Jim Watson
Member
What makes you think there are no 3 groove or 5 or 7?
There is a 3 groove PacNor .308 in the next room.
The British like 5 grooves, found on most SMLEs, No 4s, 1914s, and commercial BSAs.
So did S&W before they got into ECM, and may still.
There are aftermarket 5 groove barrels, most notably the 5R pattern
Alex Henry rifling has 7 grooves, no doubt others.
There is a 3 groove PacNor .308 in the next room.
The British like 5 grooves, found on most SMLEs, No 4s, 1914s, and commercial BSAs.
So did S&W before they got into ECM, and may still.
There are aftermarket 5 groove barrels, most notably the 5R pattern
Alex Henry rifling has 7 grooves, no doubt others.
win71
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Well dang, call me stupid!
I did not know those facts. Jim Watson you are indeed a firearms Wikipedia. My experience, like several others on this forum, is mostly with American commercial manufactured weapons. Along with some "outside America" commercial manufactures. Like you I too have Sakos, Mauser of course, Saures, Parker Halls and others but all are well known commercially produced firearms.
So my question is still if these manufactures of 3, 5, or 7 groove rifling worked out well how come nobody in the high production factories today, or even the days of old, are not using them.
I only ask because I'm still uneducated and wonder why 3 groove may be as good or better than 2 or 4, or if 5 may be better than 4 or 6, and on and on.
Hey, every rifle I own, reload for and shoot, shoots good. Varmint rifles around .250 to .500 MOA and hunting rifles .500 to 1.0 MOA. I know what the barrel twist is in all of them. I never gave a thought about how many grooves were there.
I did not know those facts. Jim Watson you are indeed a firearms Wikipedia. My experience, like several others on this forum, is mostly with American commercial manufactured weapons. Along with some "outside America" commercial manufactures. Like you I too have Sakos, Mauser of course, Saures, Parker Halls and others but all are well known commercially produced firearms.
So my question is still if these manufactures of 3, 5, or 7 groove rifling worked out well how come nobody in the high production factories today, or even the days of old, are not using them.
I only ask because I'm still uneducated and wonder why 3 groove may be as good or better than 2 or 4, or if 5 may be better than 4 or 6, and on and on.
Hey, every rifle I own, reload for and shoot, shoots good. Varmint rifles around .250 to .500 MOA and hunting rifles .500 to 1.0 MOA. I know what the barrel twist is in all of them. I never gave a thought about how many grooves were there.
Skylerbone
Member
Win71,
http://www.remington.com/products/firearms/tactical/centerfire-tactical/model-700-target-tactical.aspx
Smith & Wesson owned Thompson Center also produces a large number of 5R rifles.
http://www.remington.com/products/firearms/tactical/centerfire-tactical/model-700-target-tactical.aspx
Smith & Wesson owned Thompson Center also produces a large number of 5R rifles.
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