I recently obtained an R93 Blaser barrel in a 7.5 swiss I have a set of Redding dies that should be in next week the only data that I have is in my Hornady manual That is where I will start with but was wondering if anybody had any information that you think might be helpful.

Hodgdon has data as well, and this data is on their web site. While it appears to have not been tested in a pressure barrel, an R93 is strong enough to leave you room for error.

Try the reloading section of swissrifles.com. The Swiss military actually had two chamber configuations, one with a smaller shoulder diameter for the 1911 rifle and a larger shoulder for the 1931 model. Dies for both versions are available from various U.S. companies.Brass is available from Norma (expensive) or can be made from .284 Win brass if your extractor will handle the smaller rim diameter. This option results in excellent brass. The 7.5x55 is a great round, enjoy.

quote:

The 7.5x55 is a great round, enjoy.

I second that motion. So is the 7.5x53.5 French.

Had the U.S. had either, I am not sure how much either the .308 or .30-'06 would have prospered. The Swiss round(s) have nominally the same bullet diameter, and a case length and capacity between the two Yankee .30s. I.e., 51 m/m for the .308, 54.5 mm/m for the 7.5 Swiss, and 63 m/m for the good old '06.


I don't know about your rifle, but mine (a K-31 and a Winchester M'88) both pull the fired .284 cases from the chamber(s) with zero problems.

You don't have to buy expensive Norma brass or make it from 284. Prvi Partizan makes ammo (that I've bought for something like $7 per box of 20 from SOG) and cases with the Graf's headstamp that Graf's sells for $30.50/100, shipped. Good quality brass.

Many shooters use 4064 in the 7.5x55 but
I have had my best results with 4350 and
DP86 (bulk AA3100) with bullets from 110 to
180 grain. This is in a K31 service rifle,
using Redding dies and both reformed 284Win
brass and Swiss Thun brass. Ballistics sit
right between the .308 Winchester and the
30-06, retaining the inherent accuracy of
the former. Excellent cartridge.

good shooting, dxr

thanks gentlemen I ordered a k31 today so I could fiddle with them both at the same time will post my thoughts in the next week or two.

My K-31s all shoot IMR 4064 and tnts, 147 nato bulk, M-1 pulldowns, 168 /175 match bullets very well. Better bullets, better groups. The bulk data 85 works well to at the 50 grain level too for the 168 pills. Short throat in these guns, use a comparator. A lesser locking power than the K-98s it is said. I use a comparator and set cartridge headspace at .002 less than fired . Darn fine cartridge. ned

I also used data from Swissrifle.com.
My 4 K-31's work with H-4350 or W760 with 165 Hornady.
Hunting load for my scout scoped rifle is IMR 4350 and 150 partition gold moly.

Cheap load is 147g pulled fmj and WC846.

Privi Partisan also makes 7.5 Swiss for about $35 per hundred. My batch of 300 had less than a 3 grain variation from lightest to heaviest.

Rich
DRSS

With the 7.65 Mauser and the 7.5X55 around I wonder why many of the other 30 calibers were ever designed.

The "Not Invented Here Syndrome," of course.

Mauser, incidentally, copied his modern smokeless cartridge, bullet and rifling designs directly from the Swiss and the French. Rubin, the Swiss guy we mainly remember as the name after the hyphen in Schmidt-Rubin, was using bottleneck cases with rimless extractor grooves in the mid 1880s. The rest of the Europeans got the idea from him. He also anticipated everyone else by using spitzer, boattail, bronze jacketed, lead core bullets in the mid-'80s. They were too difficult and expensive to manufacture initially, and the Swiss adopted a paper patched lead bullet with an iron nose cap instead, but what Rubin had in mind originally was something much more like what finally got adopted in 1911 and kept around till the '90s.

It's interesting to note how many gun magazine articles have been written about the innovative design of the .284 Winchester cartridge, which is just the old 7.5 Swiss necked down to 7mm and "Improved," Atkins-style. I'd say the recent crop of short magnums are Rubin-style cartridges, loaded to higher pressures than the Schmidt rifle was intended to handle.

@all

In a modern Rifle the 7,5x55 Schmidt&Rubin cartridge is able to perform very well. I have developed a load which is outstanding in accuracy and terminal performance

I have used new cases from Thun:

Bullet: Gian-Marchet® Guisan 142 Grains (or 9,2 gram)
Case: Thun Swiss
Primer: Rottweil R5341
Powder: Rottweil R903 54,50 Grains
OAL: 80,70 mm
Pressure: 3595 Bar
Muzzlevelocity: 935 m/s
Muzzle Energy: 4021 Joules




The loaded cartridge looks pretty sexy! I like this round very much because we have in Switzerland access to various 300 m shooting ranges. The surplus ammo is very cheap so I can save a lot of money by shooting the GP11 ammo.

Good shooting and good hunting

Collani

Over here in the US, by our standards, GP-11 isn't very cheap surplus.

Sure is good ammo!

I like the looks of your handload!

Cheap GP-11 That would be nice. What dies do most of you use for the K31 I have been using Lee dies and have no problem, But some one on this forum said they where out of spec for this rifle.

Ron

I know Aleko of Heritage Arms has a 7.5x55 bbl for his Blaser and has shot some very good groups with it.

I am not sure if he reloads for it or not, but I know he likes the calibre a lot.

I believe the claim that the dies are out of spec for the K-31 is in error.

The K-31 uses the same GP-11 ammunition as the K-11. It has a different chamber specification in a number of respects including the throating, and a larger shoulder diameter with reduced body taper. One die manufacturer, I think it's Redding, has brought out dies that more closely match the K-31 chamber spec to reduce working of the brass for cases that will only be fired in K-31s. It's more accurate to say that those dies are out of spec for other Swiss rifles like K-11s. They might not adequately size down cases fired in a K-31 enough to easily chamber in a K-11. The other dies are not out of spec for K-31s.

One has to remember that the Swiss Army didn't intend to reload cartridges for these things. Making the cartridges a little looser fit in the chamber enhanced feeding reliability with dirt on the rounds. We're still not talking about the huge case expansion you see with .303 British and some other military cartridges of the day.

Redding reams its FL die to the (larger) K31 dimension and thus sized cases will not chamber in a 1911. Other makers use the smaller 1911 chamber dimension, which also chamber in the K31, at the expense of (much) harder sizing effort and a shorter case life (overworked).

7,5x55 ammo can be quite accurate as shown with these 5-shots groups at 100 m, out of one of my scoped K31 (1938 manufacture !).

The older Redding dies are for the 1911 chamber, the label on mine says "7.5 Swiss". The dies Redding has made the last couple of years are for the K31 chamber, and I believe the label says "7.5x55". If you contact Redding directly, you can still get dies dimensioned for the 1911 chamber instead of the K31 chamber.

If you neck size, as with the Lee collet dies, you can shoot and load quite a few times with moderate pressure loads before having to full length size. I haven't had to do it yet, actually, so I can't say how many times. I expect that the problem will be with case necks work hardening and splitting or rebounding off the mandrel and giving insufficient holding tension on the bullet without annealing before having problems chambering the cartridge, as is generally the case with turnbolt actions.

But I only have one K-31 and don't have to worry about sizing to interchange ammo between rifles.

I bought a partial box of 7.5X55 to use for a 7.5X54 reloading project long before 7.5X54 boxer primed brass was readily available in the US. This was also long before the K31 were seen here too.
So I concluded that the 10 or so fired cases in the box had been fired in a 1911 SR.
I could look into the case mouths with a Mag light and see a partial separation ring in those cases. I sectioned some of the cases and then tossed all of the fired ones.
Based on my experience they would have probably separated with the first reload. Use caution loading for a 1911.