03A3 two grove

[Freightman]

Well I got to the range today to try out some loads, all cast loads used the LEE 200gr boolit. 20gr 4477 shot a 1.25" group 10 shots at 50 yds, then 10 shots 19.5gr SR4759 .75" at 50 yds. Then I had 10 shots of 150gr FMJ sized down Czech silver tip bullets to .309 .50" at the same 50 yds loaded with 63 gr WC860. Temp 90 (first day below 105+ in a week)wind corning 60*from right to left at 20/25 mph reason for the 50 yds as it is protected to that distance and open at longer ranges.
Did find out that down loading WC820 is not a good idea as it stuck a boolit in my 45/70, o'well had to try.
All in all had a great day shot 150 rounds from my .357 Blackhawk 170g SWC, and picked up 200# range scrap. Was the only one there from 11 AM to4 PM, took my lunch and five bottles of water. Need to do that more often.

[Ben]

Reduced loads with ball powder often times will do that.

I steer clear of reduced loads with ball powder myself.

Ben

[Freightman]

I do to but the man I got the powder from said he had good luck in a 30/06
"HE THOUGHT"
So I had to try.

[Ben]

"HE THOUGHT" may well be the key to that one...? ? ?

[MtGun44]

Just as long as one bullet doesn't fine the previous one parked in the fast lane. . . . . . . .

Bill

[missionary5155]

Good morning
Those two groove barrels were a war time expediate that actually do well with cast. I would not dought with some load development you will find it is as good a cast shooter as athe standard barrels are. I shoot bowling pins with mine & at 100 yards with cross sticks I can hit 8 out of 10 generally and sometimes get all ten with a 200 gr RN. I think the shooter is the flaw..
Mike in Peru

[doubs43]

The two groove barrels were easier and quicker to manufacture. According to wartime testing, they were the equal of four or five groove barrels in terms of accuracy. As the previous poster says, they seem to work quite well with cast boolits.

[Larry Gibson]

"According to wartime testing, they were the equal of four or five groove barrels in terms of accuracy."

Many assume that the 2 groove barrels were "as accurate" as the 4, 5 and 6 groove barrels but that isn't the case. The testing showed 2 groove barrels accuracy was within the accuracy specifications for the service rifle. Thus 2 groove barrels were used. Those were fairly generous accuracy specifications BTW. Two groove barrels will shoot quite nicely, especially with cast but at 300+ yards the difference in accuracy will become apparent. Since most shoot cast well under that range it is a moot point.

If you doubt this then ask yourself; since 2 groove barrels are cheaper and quicker to make then, if they are "equal in accuracy", why aren't any 2 groove barrels being made and used today? The answer is; they are not the equal in accuracy of 4, 5, 6 or more groove barrels. Again, not saying 2 groove barrels can't be "accurate", just clarifying the old myth that they are not the "accuracy equal" of 4, 5 or 6 groove barrels.

Larry Gibson

[George Tucker]

Larry, your probebly right, yrs ago a friend had a 2 groove barrel, it was chambered in 30-06 Ackley, he ask me to sight it in for him, that was one of the most accurate rifles, that i have ever shot in 30 cal, George.

[Multigunner]

My Savage No.4 two groove barrel is extremely accurate , but only with my taylored handloads using Hornady bullets designed to bump up in oversized bores.
Accuracy with Milspec ammo was better than most, but most commercial sporting ammo was not accurate at all.
The Savage two groove has narrower grooves than the British two groove barrels made for their No.4, or the two groove barrels used for U S military rifles of the era.

The two groove Savage probably does give up some accuracy potential, but would seem to be more recruit proof when it comes to damaging the lands by ham handed cleaning practices.

I'd be interested in knowing the WW2 acceptable accuracy requirements for the various U S rifles.
The Farrow's Manual of Military Training gives WW1 acceptable sighting in figures for both Springfield 03 and M1917 as four out of five shots within a 2 inch square at 100 yards, with the prefered distance being two hundred yards and a four inch square.
The square being the intersection of bands of these widths overlaid on a standard target.

The Garand was expected to be slightly less accurate than the 1903, but not by much.

Some custom barrel makers have recently begun using three groove bores, which is a throw back to the Trapdoor Springfield I think.

An uneven number of grooves was always considered superior, and testing of both muzzle loaders of the 1840's and cartridge rifles of the early 20th century seems to bear this out.
A three groove should shoot better than either a two or a four groove barrel, a five groove should shoot better than a four, but a six groove being a multiple of three should shoot best of all, with all other factors being equal of course.
Seven grooves was considered best for a muzzle loader, but seven grooves in .30 bore would leave the lands rather slender and more easily damaged.
The micro groove bores of some Lever Action rifles are said to be finicky, but The most accurate lever action I've fired was a Marlin .30-30. I never bothered to examine the bore of that rifle, but it was far more accurate than I had expected possible for a lever action.

[303Guy]

My two-groove N04 seems to be scary accurate. They do actually use the two-groove principle in high grade barrels in the form of three-groove. That principle being bore diameter with narrow grooves cut into it. Not sure of the three-groove bore to groove ratio but my two-grooves (both) are 85% bore. There is a trick in the throat with it being one continuous leade taper of 1° - I think? (Or is it 1.5°?) Both mine have tight tolerance bores and chambers. I'm yet to test fire my mint bore two-groove. I was told that it's very accurate. A chamfer base boolit is needed to avoid trailing edge distortion.

[Larry Gibson]

I'd be interested in knowing the WW2 acceptable accuracy requirements for the various U S rifles.

Acceptable accuracy for M1903/M1903A1s prior to WWII was 5 shots in a 4 1/2" square at 200 yards with M1 ammuntion (TR 1400-30A, dtd 10 August 1938).

The accuracy acceptance standard for M2 ammuntion (TM 9-1305-200, dtd June 1961) was a "mean radii of 7.5" at 600 yards using an accuracy test weapon (heavy barreled test action) in a test fixture (machine rest). That "mean radii" computes out to around 3 1/2 MOA. That was 10 shot groups out of a heavy barreled test weapon in a machine rest. Out of the average M1903/M1903A1/M1903A3/M1904A4 it was probably not as good. M72 is pretty much a duplicate of the M1 ammuntion made in the mid/late '30s and I've had numerous M1903s shoot to specification. However, real M2 ammuntion that meets the 2800 fps specification is hard to find. What little I have found over the years is usually fairly accurate but not as good as M1/M72 ammunition. Most of the M2 found post '42 is loaded to the NG requirement of 2600 fps or less. I've not found this M2 ammuntion to be very consitent or accurate either in 4 or 2 groove barrels.

My M1903A1 (SA 9-19 4 groove barrel) with M118 bullet loads or M72 shoots 2 moa or less and 3 -4 moa, at best, with most M2 ammunition. My M1903A3 (SC 9-43 4 groove barrel) will shoot 1 - 1 1/2 moa with most M72 ammuntion. My M1903 National Match Type II (RA 9-43 4 groove barrel) replicant will shoot 1 moa with M72 and less than moa with 175 MK loads. These are all 10 shot groups or 22 shot match strings. One time I had access to 6 excellent condition M1902A4s and found that with M72 ammuntion they would shoot pretty close to 2 moa out to 600 yards. I've also had numerous other M1903 of various models over the years and found them, if in excellent condition, to be capable of 2 moa with M72 ammuntion. Yes I have shot some spectacular 3 and 5 shot groups with them, even with cast bullets, but overall with M2 ammuntion the accuracy has been 3 - 4 moa. Sometimes with some lots of M2 ammuntion it has been as bad as 6 moa, again talking 10+ shot groups here.

Larry Gibson

[leadman]

When I recieved my Remington 1903a3 2 groove from the CMP I cleaned it and took my hunting ammo for my Savage to the range.
The first 3 shots went into a groups of .316" at 100 yards off the bench. the fourth opened the group to less than 1 1/4". The first hole was in the X of the bullseye, without touching the sights.
To say I was pleased was an understatement! I still have that target.

That ammo was a little warm for that gun but sure did shoot well.

I have shot 1 moa groups with cast at 200 yards with it.

[Multigunner]

So the rifles remained accurate but ammunition quality fell off during wartime production, at least for M2 Ball.

With top quality heavy Ball such as M1 Ball or the high accuracy loadings the pre WW2 1903 and 03A1 were still in the running as the most accurate of bolt action military rifles, the 03A3 and 03A4 were slightly less accurate on the whole.

I've occasionally run across posts from 03A3 owners who found their own two groove barrels to be far out of specs. I would hazzard a guess that this was not a very common situation, but points to some slack in quality control during WW2 manufacturing pressures.

[Edited to add]
On reflection the reported out of spec two groove 03A3 barrels from the descriptions may well have been barrels damaged by launching rifle grenades. Until the bugs of the Garand grenade launchers were worked out Springfield bolt actions were issued for the purpose of grenade launching.
This might explain why some 03A3 or 03 Barrels were found to be very loose in spots, swollen internally rather than cut that way at the factory.
SMLE and No.4 barrels also occasionally have such loose areas, and probably for the same reasons.

Improper use of a steel cleaning rod can also batter down the lands mid bore, if a rod is thrust in from the muzzle and bangs against the bolt face vibration twangs the steel rod against the lands mid way of the bore. This was noted as a commonly found bore damage of the Mosin Nagant and some Asian long barreled rifles when modern breech loaders first came into use, many peasant troops used to muzzle loading weapons didn't take instructions too well, and the rifles suffered.

An 03A4 rifle might be exceptionally accurate with decent ammunition but hampered by unsuitable M2 Ball.
Its common to hear of British snipers purloning RAF and Ground MG ammunition as these were made to tighter specs than the Infantry Ball. Also I've heard that USMC Snipers often tried to get ammo from the Naval Aviators supplies but were seldom successful.
The 168 grain AP was considered to be pretty accurate, probably because the bullets are very long for their weight, and at one time preferred for target shooting.
The tighter specs on primers used for ammo that might be used in synchonized guns was often given as why aerial gun ammo was preferred by snipers.

Its like the archer spending more time on his arrows than on the bow. The best bow can't make up for a poor quality arrow.

[gew98]

Ed ; As I have taken the time to relate here the experiances of Dunlap and George , whom both had prewar shooting experiance with service rifles and ammunition and gobs of wartime experiance during the war BOTH articulate gentlemen pointed out the glaring faults of the 1903's delicate sights , improper bedding , mechanical breakages and the sad 03A4.
They both pointed out the generally mediocre results using M2 ball , but the issue 'Bow' being as subpar as the 'arrows' sure had alot more to do with the overall lack of quality in the issue 1903.
The germans and brits went to the trouble of identifying rifles which showed promise in accuracy and turned them over for conversion to sniping rifles , sadly the US did not do the same.
At the same time oddly enough most of the gun nuts of the 2nd war era panned the two groove barrel...but as noted and my experiances mirror those mentioned that the two groove barrels did just fine.

[bob208]

my a4 has a 2 groove barrel and it shoots past 300 yds.

[303Guy]

The two-groove might be sensitive to bullet style due to the degree of swaging of the boolit in the bore, upsetting the base unevenly.

[gew98]

I personally would not have thought that potential bullet deformation so...would or could cause that...but you got me thinking.

[303Guy]

Here's a bullet the does well in my two-groove.

http://i388.photobucket.com/albums/oo327/303Guy/MVC-201F.jpg

I put it down to the jacket base shape as well as the throat configuration which I would think would centre and align a bullet quite well. It tapers from chamber end at .318 down to bore of .304 in one continuous taper. GC and PB do not do well.

Here one can see the distorted base.

http://i388.photobucket.com/albums/oo327/303Guy/MVC-871F.jpg

Plain base are even more marked.

http://i388.photobucket.com/albums/oo327/303Guy/Patchfailure2.jpg