Looking at having the old 03 Springfield rebored to .338 and chambered to .338-06. Any advantage one way or the other between three-groove and five-groove in a hunting rifle?

Bill

Are you going to go thru J.E.S. reboring?

I am very pleased with his work

As far as a 3 or 5 groove I cant really give much of an opinion.. My 9.3x62 that Jes did is a 3 groove and it shoots excellent. I have a 1917 Remington Id like to get rebored by him also I just cant decide what caliber to do it in.....

I traded all my .35 Rem ammo to the gent that bought your Model 8 by the way. Good guy to deal with.

Cal30

No difference; two or more seem to work well.

I recently installed a new, surplus two-groove barrel on an '03 Mark I, action. Bedded it into a Boyd's laminate stock, and it shoots under an inch. No, anything more than one, as long as its done well, works just fine.

Cal, yes, leaning toward JES, although I got a PM about another good reborer.

I had JES do a Winchester 64 (don't tell anyone ;-)) from 30 caliber the 38-55 with three-groove. They did a swell job with a nice smooth bore. It's an open sight rifle but seems to shoot as well as I can do with open sights.

I always wondered if one groove would work.....in 1943 they found that two groove Springfield barrels give lower pressure than the 4 grooves.

polygonal rifling

Has not caught on for rifles.

I know some Palma Match shooters that used 3 groove barrels.
They stated they were able to get higher velocities, with less pressure.

quote:

Originally posted by dpcd:
Has not caught on for rifles.

I have a polygon barrel on my McMillian 308 Match rifle. Not only does it shoot great, but it is very easy to clean.

quote:

Originally posted by dpcd:
Has not caught on for rifles.

I have one on a short throat .257 Wby Mag and another on order for a Palma rifle. So far they shoot great and clean easy. My only gripe is that I cannot brush them as the brushes just slide down bore without following rifling so all you can do it patch them out.

Ok, that is two rifles out of millions; I mean polygonal is not common at all compared with standard grooves.
I have a 308 with a pac-nor 3 groove barrel. Shoots ok; not great but I do not know the reason.

I had a 6.5-06 with a Pac-Nor 3-groove. Shot decent. Had one of their 338 barrels for my 338-06. They steered me away from their polygonal rifling. Said they have the best results with their 6-groove. I have been curious as to how the number of grooves would affect the jacket integrity of a bullet for hunting situations. I kind of had it in my mind that the higher the number of grooves(conventional rifling), the more "perforations" it puts in the jacket as it goes down the barrel. I thought maybe the smooth transition between the lands and grooves that the polygonal rifling provided would be easier on the jacket. I have no proof, it was just something I was thinking about while I was mowing the yard.

What should you pick? I would ask your barrel man. Maybe he would have some informal statistics on what performs better for a given caliber. My test sample is small, but I have seen no definitive proof that a certain number of grooves will shoot better, give more velocity, or clean up easier. Most of my rifles have 5 or 6 groove barrels. I have seen some substantial differences between two identical barrels, ordered at the same time, and from the same company. I had a pair of his and hers 6.5x55's made for my wife and I. Hers loves partitions and mine wont shoot them at all. With identical loads, hers always shoots faster. meh... Regardless, If I can get a rifle to shoot minute of deer from a field position, I'm happy.

P.S. Pac-Nor did say that they weren't able to achieve the best interior finish on their polygonal barrels as they would with the conventional rifling. I think it was something about how the lead slug used to lapped the barrel wouldn't track right. But don't go spreading that as I don't recall all the details.

Seem to remember that the Brits did some tests with the various models and sources of No 4 rifles they made and had made in WWII.

Everything in terms of rifling from the Savage 2-groove to the Enfield 5-groove.

The story goes the 5-groove had been settled upon by calculation and experimentation. There was no difference, but the Brits went back to 5-groove anyway -"Because that's the way they SHOULD be made".

The details could be wrong, but I seem to remember reading it in RSA Man-Magnum recently.

quote:

Originally posted by dpcd:
Ok, that is two rifles out of millions; I mean polygonal is not common at all compared with standard grooves.
I have a 308 with a pac-nor 3 groove barrel. Shoots ok; not great but I do not know the reason.

I understood you. I am the only guy I know shooting Poly. I mostly shoot 6-groove Lilja and Douglas barrels. A buddy of mine on the Palma teams shoots 3-groove Lilja. 5R barrels are all the rage with a couple guys I know because we shoot them at work. My next barrel will be a canted land Broughton. I honestly don't think it makes a difference; good barrels are good barrels.

Apprentice,
As for Pac-nor's comment about the Poly you are likely right. When I contacted Chris to tell him I couldn't brush the barrel he said, "I know, you're just going to have to soak it and patch it." Makes sense that if a tight, bristly brush won't follow the rifling that a soft lead lap won't either.

I had a custom 257 Roberts built by a close friend. He put a Lilja 3 groove on it. It's on a blueprinted Mdl 70 action in a very nice piece of walnut. Sadly it will only shoot around 3/8" but I really haven't varied the loads much from the breaking in period. Seems to clean easily. I also have a custom 03 military that has been shortened to 16 1/2" and all the hardware and wood refitted. Also has had the bolt handle forged by Les Womack at least it's so stamped on the bolt root. A G&H mount has been installed with a Lyman Alaskan. It has a nice precision compass inletted in the side of the buttstock. The barrel is the original 2 groove and with factory 150gr Federals it shoots less than an inch. Supposedly built for a sportswriter to use as a backup while fishing for salmon in alaska.