Remington 5R Barrel

[8ptbuk]

Ive found a gun shop that has a special run of 7oo rifles that have a 5R barrel on them. Owner says remington has only made 250 of them. Does anybody know anything about a 5R barrel What is it design for ?? No. of riflings ?? The Rifle Im looking at looks sort like a sendero, and is chambered for a 300 Win. mag. Any Info would be very much appreciated !!!!

[rossman40]

The 5R rifling is not something new, it dates back to the early Enfields. To start with it will always have a odd number lands/grooves, in the case of 5R five lands/grooves but I have seen 7R in larger calibers and 3R in .22. The purpose is that the bullet is not squeezed between two lands. The lands can be canted or radiused. The end result is less stress on the bullet which also means less fouling and higher speed. At the turn of the century Enfields used this style but later went with more conventional rifling. After WWII the Russians (the "R" in 5R actually stands for Russian, not radiused) brought it back to get better barrel life with copper plated steel jacketed ammo. Boots Obermeyer came across it and started using it, most notably in the barrels he supplied to the Navy/Knights Armament for the SR-25 program. Mike Rock (Mike apprenticed under Boots) after he got his own shop, started cutting barrels for Remington and his 5R barrels first appeared on the PSS model (now just the 700P) of the 700 but due to cost Remington went back to conventional button rifling. The rifling started being used on the M-24 (more correctly Mike Rocks cut rifled 5R barrels are used).

Supposedly I have heard that Remington now has 5R button rifling. How a button rifled Remington factory barrel compares to Obermeyer or Rock Creek cut rifled barrel is probly night and day.

It boils down to 5R rifling giving a bit more speed and less fouling which means more consistent MVs and reduced clean up.

[8ptbuk]

Wow !!!! I really appreciate you taking the time to reply. I looked around but never found anything near what I learned from you !!!!!Thanks Rossman !!!!

[olegburn]

Very informative indeed!
WHich caliber Russians had in odd lands/grooves,rossman?
I thought that the steel was only used in casings and bullets had copper jackets...

[rossman40]

Copper plated or washed mild steel jackets are common for military ammo. A lot of US WWII 30-06 and even Korean era was that way. During WWII copper was needed more for electrical uses. The Germans even put commerce raiders and even a few U-boats on the west coast of South America to stop copper coming to the US from South America during WWII.

A lot of the Russian, Warsaw Pact and Chinese military ammo have copper plated steel jacketed bullets and even steel cases. Of course the common stuff is 7.62X39 and 7.62X54R but even 7.62 and 9mm pistol ammo. I have even seem 8mm Yugo ammo steel jacketed. Some of the Danish 30-06 the CMP was selling had steel jackets and I picked up some Talon US surplus re-man ammo that was steel jacketed. I recently bought some new production Geco 9mm pistol ammo that had steel jackets. When in doubt, whip it out, at least the magnet. If it sticks to the bullet it has a steel jacket or maybe a core but if it has a steel core it is illegal to import as it is classified as AP. Wolf, S&B and Barnaul will slip you steel jacketed bullets.

[rossman40]

I missed the other question. The AKs use a 4 lands/grooves barrel and if I remember right the RPKs and PKMs used the 5 lands/grooves. Of course the Russians also used chromed chambers and bores because of the crappy ammo.

[olegburn]

How about that!
While back in Russia never thought of jackets being steel.
Wondering though if it will affect the barrel wear?
Chrome in the barrels is pretty much standard in Russian military small arms IIRC. Most ammo had been dipped in laccuer for rust protection I remember for sure.
Crappy ammo issue was resolved by large quantities of the same and robust AK and PK design.
You have military background,rossman? As much knowledge I get reading your post makes me think that way.Or perhaps weapons related industry...

[rossman40]

I retired out of the Army (actually the National Guard) and my specialty was artillery/fire support. To do my job well I had to know the capabilities of every weapon and munition on the battlefield, from a pistol to a B-52.

[jims]

Rossman40: I had a 13E40 MOS in the Army but I never really worked that at all, I worked in a place they called the Head Shed but we referred to as the Nut Hut at Fort Hood. Initially with the 1st Armor and later the 1st Cav.
I thought the R stood for radiused, I did not know it stood for Russian. Learn something new here everyday.

[rossman40]

Jim , that was back in the days when the even the FOs carried a 13E MOS. In 1979 the FOs switched to a 13F and the infantry lost their own mortar FOs and the 13Fs had the responsibility for planning and calling all fire support including air support and naval gunfire plus all the coordination. I've did my time in the "head shed" plotting targets, No Fire Areas, having to explain Air Space Coordination to helicopter pilots and having to tell a Major what to tell the Brigade CO.

Somewhere in a article I read that Boots himself said that the 5R stood for 5 lands, Russian pattern. The Russians figured out that canted/radiused rifling was less stress on the bullet and stood up better when things got hot and the biggest thing is that it worked great with hammer forging. Some AKs had 5R but they decided 4 lands with the canted/radiused lands was the way to go so you see AK47s and AK74s with four lands.