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So I have both a Swiss 1911 long rifle and a K31. Obviously both of these are chambered for 7.55 Swiss. And as I do for all my other calibers I would prefer to reload for them. I've done some initial looking around and have noticed that there are dies listed specifically for both, often by the same maker. So my question is, is there a real reason for this or is it a marketing thing? Can I get away with only buying one and if so, is one (K31 vs 7.55 Swiss) preferable?
Thanks.
Everything you ever wanted to know about the rifles and their ammo is here. There are very few sites that are as comprehensive as Swiss Rifles. Reloading for 'em, including good pictures of the assorted 7.5 Swiss cartridges, is under Ammunition. They say(FAQ's) it's safe to fire modern 7.5x55 rounds in 1896/11s, 1911s and K31s. You'd have to work up a load for both rifles though.
SwissRifles
I reload with the Lee dies for 7,5x55 Swiss, FL set for collet only. For my K31.
No issues at all.
K31 and 1911 chambers differ in body taper (and throat length). Dies made specifically for K31 will not FL size cases to fit smaller 1911 chamber. Standard (1911) dies work for both.
https://www.milsurps.com/images/impo...6/1rdh06-1.jpg
Parashooter's post illustrates a basic rule for all milsurps: even if the rifles have the same nominal caliber, use only neck-sizing dies AND keep the cases separate for each rifle.
I find that a simple and reliable way to do this is to use cases from different manufacturers for different rifles.
This prevents the annoyance of getting to the range with the rifle that has the tighter chamber, and finding you have brought the ammo for the rifle with the looser chamber!
You can, of course, always full-size for the minimum chamber, but case life will be short.
[QUOTE=Patrick Chadwick;433851]Parashooter's post illustrates a basic rule for all milsurps: [I]even if the rifles have the same nominal caliber, use only neck
What do you do if you have 300 to 500 rifles in the same caliber ?
Unfortunately, neck sizing doesn't work very well for these straight-pulls unless significantly reduced loads are used. At full pressure, cases are often expanded enough that they cannot be easily chambered and extracted via a mechanizm where the bolt's turning force is applied indirectly through a cam arrangement that converts axial to radial motion. This is very different from the usual turnbolt action where all we have to do with a tight case is crank a bit more forcefully on the big handle.
7.5x55 cases that have been fired will full loads should be FL sized to avoid disappointment at the range. At the very least, sized cases should should checked in the rifle for easy chambering and extraction - before charging. Those wishing to enhance case life can learn to adjust FL sizers to produce minimal cartridge end-play while maintaining an easy fit.
My buddy used to reload for the K31. It was a absolute nightmare for him. Everything needed to be tight tolerances to get it to function reliably. Everytime he reloaded he had to trim the cases.
In comparison my for my I.G. 1889 I have never trimmed the cases (though I am going to have to now as I found I couldn't chamber rounds that would fit in the 1889 in my K1893). I could also get away with much more slop in the reloading, whereas he had to spend a lot of time making sure it was all 100% on point.
I'm not having all those trouble with my K31. I only neck-size, so they are a bit tight when chambering, but really just a tad. I sometimes have to push the handle harder or rap it with the palm just a bit.
My current brass has gone through 4 reloads and I have not trimmed it yet, although it is on my to-do list after tomorrows "session".
In barrel production, chamber reamers start out "oversized, (actually at the MAX end of the design tolerance) and, as they wear, are sharpened and re-ground to maintain the acceptable tolerances.
The first chamber cut with a brand-new reamer will be "bigger" than one cut with one on its last legs, however, BOTH will be within "spec". At the point where the reamer can no longer meet gauging after a re-grind / sharpening, it will be scrapped and a new one put into operation.
SERVICE ammo MUST fit ALL SERVICE chambers, ALL the time. Generally, service brass is fired in a service chamber ONCE and once only. I recall that the Swedes reloaded some of their 6.5 x 55 brass, on a one-time basis and strictly for use as training ammo. Anyone know if the Swiss did the same? Before lead-based priming compounds, it was a definite non-starter as a practice.
If you think Swiss chambers and brass are "funny", try reloading for all-original Japanese 6.5mm and 7.7mm rifles with original factory-cut chambers; "benchrest-grade" chambers they are NOT.
With two or three different rifles of the same nominal calibre, you may get better groups and case life from careful separation and "custom" loadings. If you are feeding a battalion's worth of rifles of the same calibre, the only sane choice is to load all the ammo the same, zero the rifles accordingly and stop worrying. When a case fails after sundry annealings, resizings and trimmings, consign it to the recycle bucket and enjoy the shooting.