7 MM Gradle Express

mljackso

My book "Cartridges of the World" had never failed me. Then I looked up the 7 mm Gradle Express cartridge. I have an old Roy Gradle custom rifle with this chambering. The 7 mm Gradle Express cannot be found in any reference book I have. It does not "Google" well either. HELP!!! What do you know about this rare Wildcat? Proprietary? round?

Hawk Carse

Well, as me and Ambrose said in your first thread, the only place I have anything about the Gradle 7mm Express is in the Ackley books. There are surely some old magazine articles about it, but my collection does not go back that far. I figure it was obsoleted when the 7mm Remington Magnum came out in 1962.
As you see, it is not in CotW, nor is it in Nonte or Donnelly.

Ackley says: "The 7mm Express was originated by the famous gunsmith Roy Gradle of Santa Barbara, California, who is now retired. Rifles for this cartridge are now being made by Ralph M. Payne.
Cases are made by making extensive changes on the .348 Winchester case, the method for which is essentially as follows.
Neck the case to .30 calibre. Fill the case with lubicating oil an place in a chamber made with a chambering reamer which is attached to an air cylinder. They cylinder is equipped with a two way valve. The upper part of the die is fitted with a 1/2 inch piston which the ari drives into the case filled with oil. The pressure being applied slowly alows time for the brass to flow into the chamber and form perfectly. The cases are removed, cleaned and then run through the standard sizing die. After the cases are formed, they are placed in a special collet and the rims turned off and a new extracting cannelure cut in one operation. The result is a completely different case in 7mm calibre, with a radius shoulder (no sharp corners.)"

Claimed velocities are very high, attributed to the short fat case shape. More likely to a willingness to run loads to high pressures, if you ask me.

Note: "Now being made" applies to when the book came out, 1962, not 2009.

Ambrose

Hawk; Assuming you could turn off the rim, turn in the extraction groove, and neck the case to 7mm, I wonder why you couldn't just fire-form the case like most improved and wildcat cases.

Hawk Carse

I don't see why you couldn't. Might have to form a false shoulder to headspace it for fireforming, or seat a bullet out into the lands like Gibbs.

It's going to be a bear to work with, though.
One source thought the Gradle Express might be formed from .300 WSM. The head diameter is close and you wouldn't have to turn the rim off .348s.

CH-4D lists loading dies and indicates they will make form dies.

JustC

rechamber to 7mm mag and be done with it.

Hawk Carse

Hard to ream a hole smaller.
The .348 parent case is a fat one.

JustC

My mistake Hawk, you are correct. Either rebarrel or sell it.

mljackso

If one were to be more of a collector than a shooter, wouldn't the rifle be worth more to keep it as is, with its rare/unusual (yes obsolete) chambering? Would it not turn a valuable collector item into a less valuable shooter to re-chamber or re-barrel it? I am fairly new at this but it seems like it would be a more valuable rifle to collectors unchanged, even though to shooters it is worthless SINCE IT WILL NOT SHOOT BECAUSE AMMO CANNOT BE FOUND OR EASILY MADE. Opinions?

perry shooter

Rare does no equal value you have to have people wanting to buy to equal value IMHO #1 firearms are made to be shot #2 there is a VERY small market for obscure wildcat chambered rifles. Unless you get TWO or more people bidding I would be willing to bet you will not have a flock of people trying to buy your rifle. It is neat to have this Item BUT[?][?][?][?]

Ambrose

Hawk; I haven't joined the 21st century yet--I'm still working with the 20th (and the 19th!). So my books don't show much on the WSM's. I have, of course, dims. on the .348. How close are they? And I agree with mljackso, leave it as is. If the rifle were mine, I'd figure out a way to get it shooting without changing the chambering. I've done it before with old, obscure wildcats and, while not easy, (or cheap!)it's not impossible. And it's fun!

JustC

Perry Shooter is right in that finding someone interested in an obscure chambering is very hard. Value, especially in a custom rifle, is really up to someone who is interested.

If you were to rebarrel, and keep the old barrel, it could always be screwed back on if you wish to sell the rifle as an obscure chambering, and in the mean time can shoot it in an easily found chambering with the new barrel.