Johnson Rifle Brass

[gunsgunsguns 0]

Hello, My first posting on this board, brand new member.

I have a question for you Johnson shooters. I picked up one for my brother many years ago, which I wish I could have afforded to keep then, but glad for my bro. Anyway, when we've fired it, it rips the heck out of the rims, making the brass useless. Is this a normal treatment of it's brass? Someone recently advised to oil the cartridges prior to loading in the rifle. He's down in the Republic of Calif, so hasn't had a chance to try this yet. Any observations. Thanks and regards, Guns

[Joseph Scott 0]

Sticking brass usually indicates the chamber needs cleaning or has minute pitting which is hard to see. Clean chamber with a shotgun brush and inspect carefully. If cases still stick, try polishing unfired rounds with Scotchbrite while holding bullet in variable speed drill. Polish brass smooth so that any imperfection in chamber will show when fired. If chamber is pitted, it can be polished with small ball hones. A 12mm size, medium coarseness with water or honing oil can do wonders. If pit is very deep, barrel needs to be set back and chamber re-reamed. Also set back center collar to maintain correct barrel position.

[ArtR 0]

Remember, brass should always be clean. NEVER OIL. You will be adding to your problems.

I had a chamber once that had a minor burr which caused cases to hang, thus ripping rims on occasion. Solved this with a friends help. We did not have a chamber reamer. We turned down a piece of wood, and then glued a piece of very fine emery paper onto it so it was same size as a finished case. Then with the "wood case" on a spindle, we inserted slowly, in and out, and slowly polished the burr off, cleaned the chamber and the chamber was back in good as new condition.

[gunsgunsguns 0]

Have you shot the Johnson and found your brass comes out fine, or are you talking in general? Galil's beat the heck out of their brass, I'm wondering if this is a Johnson problem, the chamber did not appear rough, but it has been awhile since I've had a chance to look at the weapon.

[Bob Lamoreaux 0]

I mentioned this problem with brass previously. I bought my first JSAR at Numrich in about 1961 or '62 for $95.00. It had no problem "digesting" reloaded military cartridge cases but yanked the "rim" off Norma (reloaded) cases. My understanding is that Norma cases were "softer" so the would not rapidly "work-harden" during reloading (resizing). Military cases, by the way, had a fairly significant crescent shaped "dent" or imprint from the extractor on the ejected case when fired in the JSAR. And everyone is correct about the ejection power of these rifles. Was sighting in at a bench rest one day and the JSAR threw the case over one vacant rest, hitting the shooter that the next bench! I wasn't too popular THAT day. BTW, in those days -- the late '60s -- not too many folks knew what a Johnson rifle was.

Bob Lamoreaux

[gunsgunsguns 0]

Thanks Bob, It has been awhile since I've been out with my brother shooting his Johnson rifle, but I'm sure we were probably shooting military brass, couldn't afford Norma, expecially for a .30-06. It really dinged the rim to the point that the brass was not reloadable. Someone told me that the cases should be oiled, like the Japanese machinegun (model I don't remember). Have you ever heard of this or tried it yourself? Regards, Guns

[Bob Lamoreaux 0]

Do NOT oil cases!!!! While there are some semi- and full-automatic weapons that need lubricated cases (the Pederson rifle using a parafin lub on its .276 [?] cases) and some machine guns (Hotchkiss, I think -- particularly the Japanese versions) using oiled cases, I think that common wisdom cautions against this practice. If I recall, Hatcher may have done some experimental work and found that oiled cartridges created a headspace issue that increased chamber pressure resulting in blown primers. Might be mistaken on this point, but I recall that oiled cases can create a dangerous condition. . . Maybe someone else on this board will recall or can find the source and more fully explain the "why not" involved.

Bob Lamoreaux

[Alasdair MacDonald 0]

Correct Bob, never,never oil cases for firing. It would take volumes of pages and a lot of math to explain what happens, but here is the simple version. A car engine utilizes about 15 to 20% of the fuel where a firearm uses about 20-30% making it more efficient. Such factors as metal type, thickness, heat absorbtion rate, burning rate of the powder, metallurgy of the brass to create obturation (the ability of the brass to expand and create a tight gas seal in the chamber), bullet weight, pressure curves, are all designed to keep the internal ballistic pressure to an acceptable level for safety. Engineers figure safety by the shoe size formula, "if you wear a nine, a ten feels so good that you buy an eleven" and engineer firearms on the safe side. When you oil the cases, a burnable fuel, there is the possibility that the oil will diesel and detonate causing your chamber pressure to rise faster than the bullet is moved down the barrel and causing a very dangerous pressure. If the barrel can't handle it, you may have to visit your local plastic surgeon. You are also correct in that some firearms do use oil on the cases for facilitating the feeding function. These firearms are engineered for this. Keep in mind that this attracts dirt in combat and very quickly can put the gun out of action. The WW2 Japanese Model 92 7.7 heavy machine gun used this and had an oiler above the feed tray entrance on the left side. I remember as a child putting a drop of 3 in one oil in the base of a pellet and then pumping the gun seven times. When fired the instant air pressure compressed the oil causing it to diesel and that lead pellet went out of there with great celerity. It created such a vibration that it broke the muzzle strap holding the barrel to the pump tube below. Cordially, Alasdair