7.92x33 kurz!

[bobcat93]

How on earth am i just finding this cartridge.
It looks like it could be alot to fun out of a bolt action ..especially wildcating
Neck it down to .308 for simplicity, and selection of bullets.
Maybe even a .257cal.
Like i new 25-35 on steroids
Only one gun i believe was made to fire this cartridge the MP43.
A bolt gun could prove alot of fun. Brass is hard to find but the case can be formed from cut down 308 cases.
Is any one playing around with this obsolete cartridge. Or is it truly a thing of the past.
Its got some impressive case capacity @ 34.3gr.
And a 49k psi max pressure..
I dont see why you couldnt push this little cartridge to speeds that are acceptable around here.
Who has played around with this big little cartridge

 

[nockhunter]

STG44

 

[Knotwild]

I think you are all set for ammo, brass and dies. I don't know why anyone else hasn't tried it.


Bayou Brass 7.92x33
SG Ammo 7.92x33 500 Rounds Privi Partizan
Graf & Sons RCBS 7.92x33 FL Dies

 

[Evlshnngns]

I seen my first one last week, stamped 8x33. I thought it was a 7.62x39mm at a glance. Pretty neat.

 

[bobcat93]

Does anyone have experience with cutting down cases?
Is the brass the same that far down a 308win case?
How far off the bottom of a case do you have to come up to stay out of that thick brass cup
Seems to me this is about the shortest one could cut a 308 case and still use it?
Is there a signal, or tail tell sign to cutting down brass.
What im asking is , if i cut down a case and can still anneal and form it (does that mean it is usable)
Or can that only be figured out by actual repeat firings to find out brass longevity of a wildcat.

Or does it start by picking a brass brand, cutting a case in 1/2 length ways and see what is going on with the parent case by taking measurements bown the side of a case for brass thickness.
Ive never been this far down the wildcat rabbit hole .
Of actually making a case. From another.
I hope that makes sense its kind of hard describing but i think you guys know what im saying..
No way to tell untill you sit down and start cutting anealing, forming and see what happens

 

[bobcat93]

I think you are all set for ammo, brass and dies. I don't know why anyone else hasn't tried it.


Bayou Brass 7.92x33
SG Ammo 7.92x33 500 Rounds Privi Partizan
Graf & Sons RCBS 7.92x33 FL Dies

Out of stock
Out of stock
Out of stock
That is why
Hahaha..
Maybe they only pump them out once a year.
But after some research
I watch some history of this cartridge and rifle videos
These rifles were every where in stock piles after the war. , they were gathered and sold to Pakistan or some one to farther their war efforts
So this cartridge is still in use just not in USA
Its alive still kick-n & still kill-n

 

[FNSafari]

What are you going to gain, satisfaction wise, buy going with a 7.92x33? I guess if you must, then go for it. Pesonally I would recommend a 30Br, or something based on the Lapua 6BR case. It's 38mm so you could prolly push the shoulder back and fireform it at 33mm if you went out and designed and sourced a reamer. Then you have dies to contend with. If 7.92x33 brass was readily available, that might be a different story. But, then you have the 7.62x39 Putin to think about also.

 

[bobcat93]

Just uniqueness man..style baby, STYLE!.
HAHA plus its fun to talk about
Once you neck it down to .308..its been done to death..lots of .30 cal cartridges readly available around a 34gr case capacity..
.25 cal could be even better

I did find something close that has been done already its a little larger
.308x1.50 Barnes

 

[bobcat93]

If some one wanted to make a standard 308x33 chamber
Could a 308 win barrel be set back and be done?
The same with a set of dies.
I could pick up any savage 308win rifle , and a set of lee dies and cut them with a band saw !
Have a custom wildcat hahaha
Im kidding..but is it really that simple? I think it would be.
How much would it cost to have a barrel set back and cut down a few dies
Any know..

 

[ebb]

Go with a 30 BR and get the advantage of all the work those guys spent developing it. The last guys that were all in on the 8x33 didn't fair too well.

 

[Fire Dog]

I think I remember reading an article years ago saying that the 8mm Kurtz was the inspiration for the 7.62x39 Kalashnikov.
Here is a video talking about that very thing.

 

[NuJudge]

Does anyone have experience with cutting down cases?
Is the brass the same that far down a 308win case?
How far off the bottom of a case do you have to come up to stay out of that thick brass cup
Seems to me this is about the shortest one could cut a 308 case and still use it?
Is there a signal, or tail tell sign to cutting down brass.
What im asking is , if i cut down a case and can still anneal and form it (does that mean it is usable)
Or can that only be figured out by actual repeat firings to find out brass longevity of a wildcat.

Or does it start by picking a brass brand, cutting a case in 1/2 length ways and see what is going on with the parent case by taking measurements bown the side of a case for brass thickness.
Ive never been this far down the wildcat rabbit hole .
Of actually making a case. From another.
I hope that makes sense its kind of hard describing but i think you guys know what im saying..
No way to tell untill you sit down and start cutting anealing, forming and see what happens

There are a lot of YouTube videos about making .300 BO cases, and some of them feature a Harbor Freight cut-off saw with a printed jig. There are several makers of the jigs, some makers making them for trimming specific cartridge brass down, others made for just one head size. This one would seem to work best for trimming .470” head size shorter to 33mm length: https://elite3ddesign.com/collectio...trimming-jig-auto-ejecting-brass-case-trimmer

 

[357Mag]

Does anyone have experience with cutting down cases?
Is the brass the same that far down a 308win case?
How far off the bottom of a case do you have to come up to stay out of that thick brass cup
Seems to me this is about the shortest one could cut a 308 case and still use it?
Is there a signal, or tail tell sign to cutting down brass.
What im asking is , if i cut down a case and can still anneal and form it (does that mean it is usable)
Or can that only be figured out by actual repeat firings to find out brass longevity of a wildcat.

Or does it start by picking a brass brand, cutting a case in 1/2 length ways and see what is going on with the parent case by taking measurements bown the side of a case for brass thickness.
Ive never been this far down the wildcat rabbit hole .
Of actually making a case. From another.
I hope that makes sense its kind of hard describing but i think you guys know what im saying..
No way to tell untill you sit down and start cutting anealing, forming and see what happens

Bobcat -

Howdy !

Not in necessary order….

4D reamers lists 7.9 X 33 Kurtz case capacity @ 31.2gr H2O - FWIW

I believe dimensions ( fairly close) to be:

Case oal 1.300”

Base diam = 4D’s reamer print says .467”

Shoulder diam = 4D’s reamer print says .444”

Neck Lg .3402”

Commentary:
IF one had enough straight section @ the chamber end of a .308 Win barrel….

and fore-shortened the barrel/chamber end….

to the point where the new base diam was .466” nominal.…

7 X 64 Brenneke could be utilized as the parent case for the new wildcat.
7 X 64 is .308 bolt face compatible, rimless; and has .466” base diam.
New 7 X64 cases I’ve ordered ( Norma, example ) come in w/ .464” base diam, unfired.

This notional .30 cal wildcat would have these dimensions:

Case oal. 1.6492”

Base diam = .466”

Shoulder diam = .454”

Case taper .012”

Neck Lg .3032

Shoulder “ height “ ( 2D side view ) = .1520”

Combined rim thickness & extractor groove “ height “ ( 2D side side view ) = .1380”

“Base-to-shoulder dimension” ( frustrum taken from 7 X 64 Brenneke “cone“ ) = 1.0560”

Note: since 7 X 64 has 2.520” case oal, the notional wildcat detailed above would represent a shortening of the parent case by some .8708”.

Note:

Amongst more common “ factory “cases seen today, the next smaller base diam than .466” of the 7 X 64 Brenneke, would be the .35 Remington… as far as common “rimless” cases go ( IMHO ).

If the .308 barrel were foreshortened to accommodate use of .35 Remington brass as the parent case, final case capacity would be notably lower than the 1st wildcat mentioned
above.

Yeh… one could go w/ a foreshortened .308 chamber, but…. one would really need to want to do it….. given other known/proven .30 calibre wildcats.


With regards,
357Mag

 

[357Mag]

If some one wanted to make a standard 308x33 chamber
Could a 308 win barrel be set back and be done?
The same with a set of dies.
I could pick up any savage 308win rifle , and a set of lee dies and cut them with a band saw !
Have a custom wildcat hahaha
Im kidding..but is it really that simple? I think it would be.
How much would it cost to have a barrel set back and cut down a few dies
Any know..

Bobcat -

Ooops !! Forgot to mention in previous post response, above…..

For the foreshortened .308 chamber-based wildcat, .35 Remington brass would be untennable. .35 Remington only has a .454”-ish base diam to start with.
There would be no case taper in the final wildcat, as .308Win has a .454”-ish shoulder diam.

I should have been more clear about that.


With regards,
357Mag

 

[SKWERLZ]

An easily made modern interpretation could be a 6 arc or 6.5 grendle necked up to 308.

 

[Laurie]

Way back (1960s) Frank C Barnes the noted bullet and cartridge designer / experimenter looked at the 7.92X33 and 7.62X39 Soviet and liked what he saw in their internal ballistics efficiency. NATO had at that time only recently adopted the 7.62X51mm T65E3 design at US insistence. (Other NATO members wanted a smaller 'intermediate' cartridge typified by the British 280/30 aka 7X43mm experimental cartridge.)

https://en.wikipedia.org/wiki/.280_British

Like many, Barnes believed the 7.62 Nato adoption was a mistake and designed / tested the 308x1.5" alternative, a very accurate and efficient little number. Given that the US had barely managed to debug the M14 rifle at the time and only just started widespread unit issue, Barnes's chances of getting the military bureaucracy to change its mind were of course nil.

Barnes' little cartridge started with a 308 Win case and some pretty heroic trimming / reforming / annealing to reduce its length by over half an inch and retain a suitable body taper, so it never caught on. Nevertheless a surprising number of rifles were built for it by keen experimenters. (I once looked at and handled a beautiful light deer rifle built by noted UK gunsmith Norman Clark on a Mauser '95 action. Short, light and beautifully balanced it shot the 125gn Nosler Ballistic Tip with excellent ballistics, accuracy, and little recoil, also fed properly from the altered magazine.)

308X1.5" (7.62X38mm) isn't far from what you're trying to achieve with only slightly greater capacity and performance. In the days before the bean counters, then 'venture capitalists' ruined companies like Remington and Winchester, people in the American gun industry were also very interested in this wildcat, in particular Mike Walker, Remington's chief design engineer. Walker also like liked the concept and the result was the BR series of cartridges. As with Barnes, BR cases were formed from 308 Win, but because of the very great difficulties involved in such a radical reforming exercise, the company produced a special small primer, reduced size flash-hole version of the 308 Win with, crucially, very light, thin walls to help reforming - the 308 Win 'Competition' case, aka 308 UBBR (unformed basic BR).

Even so, reforming the case took multiple trimming and form steps with IIRC a four-die form set, and it was only when Norma adopted and produced the design in 6mm form that the BR finally saw widespread adoption. So, what you plan is no easy task by any means, and as some others have pointed out, all the work gives you a result not much different from the .30BR.

 

[joshb]

^^^^^^^^ Listen to Laurie!^^^^^^^^^
30br is the easy button. Wanna be different? Build it in pink!