7x55mm wildcat reloading

[Jimmy Bakken]

Hello and thank you for viewing my thread. Im new to reloading and have recently bought a firearm to start with as i am also interested in custom cartridges. Its an old swedish krag jorgenson originally in 6.5x55mm that was cut down to carbine length had a williams peep sight added with custon stock and has been necked up to 7mm. My question is, where do i start with reloading data for this cartridge and has anyone seen this specific type before, if so does someone have reloading data or have an idea of its performance?

 

[KMart]

If you do not know the person that originally had this wildcat made or the gunsmith that did it, I would have a chamber cast made to be sure exactly what it is. I have not come across any 7x55 reloading data.
Does this rifle come with dies for your reloading?
Is the barrel stamped with 7x55? If it is marked 7x55, it could be a mismark and is really a 7.5x55.

If it is what you think it is, data for the older military 7x57 Mauser should be a good starting place.

Again, find out exactly what you have before you start loading for it.

 

[Zero333]

Sounds like you should be able to use 7mm-08 data.
6.5x55 has a hair more powder capacity than the 7mm-08.

Working with wildcats is not for beginners.

You have to learn to read pressure signs when developing loads.
https://www.primalrights.com/library/articles/understanding-pressure

A chamber cast is a must, and it's something you can do yourself with cerrosafe from Brownnells and I'm sure other places carry it as well.

If you don't have reloading dies then you have 2 options....

1- Get 6.5x55 bushing dies and figure out what range of bushing you'll need for your brass (have to learn how bushing dies work). Get an expander mandrel to neck up to 7mm.

2- Get custom dies from CH4D or Whidden Gunworks.

 

[Kurz]

Jimmy Bakken,

Im new to reloading and have recently bought a firearm to start with as i am also interested in custom cartridges. Its an old swedish krag jorgenson originally in 6.5x55mm that was cut down to carbine length had a williams peep sight added with custon stock and has been necked up to 7mm. My question is, where do i start with reloading data for this cartridge and has anyone seen this specific type before, if so does someone have reloading data or have an idea of its performance?

Here are the pressure suggestions regarding the Swedish Krag-Jorgenson action:

In Norway, the pressure of the 6,5 Krag ammunition was set down to approximately 3000 BAR, later(in the 70s) it was even sat down to 2800 BAR (before WW2 pressure on Krag ammo was the same as pressure on swedish mauser ammo, approx 3100 BAR). Today 6,5X55 Swedish has a max pressure of 3800 BAR.

2800BAR = 40600PSI
3100BAR= 45000PSI
3800 BAR=55000PSI

Generally speaking, selection of a new (to you) wildcat to learn reloading is a difficult proposition at best. Usually we suggest a common cartridge with plenty of data available so you can spend your time learning the reloading procedures and not have to worry about safe loads. Reloading for an uncommon wildcat, having no previous experience is a very steep learning curve, especially when you're talking about a fairly weak action to begin with.

Personally, I would put this one aside until you achieve some more advanced experience with reloading. Faces are hard to replace...

Respectfully.

 

[boltman13]

All of the advice above is excellent and deserves your careful consideration. My advice if you decide to move forward now is to consider the starting loads for the 7X57 Mauser on an older Model 93 or 95 action as a stopping point after careful working up from at least a 10% reduction in that load. Use a light bullet no more than 140 grs.. Powders suitable for the 7X57 should work. Be sure to have the rifle checked by a rifle smith. A chamber cast and confirmation of a 7mm barrel are a must. Expanding the neck of new 6.5X55 brass to 7mm should be no problem if the shoulder geometry is really the same as the 6.5X55 case. You could even do it in two stages, 0.277" first then 7mm. If you can get an experienced reloader to help it would be a good idea. If you get this old girl working it would make a good short to mid range deer rifle. Let us know how it is going and above all BE SAFE.