as for weak actions the germans proved this when they converted several to 8mm and are considered more dangerous to shoot than low serial number springfields. for the low pressures that their intended cartridges are capable of packing, sure the carcano has a plenty strong action but compared to other rifles of the age they just were not strong at all, one reason you don't see a lot of rechambered carcanos out there.
If you have a reference for this I would be interested in reading it.
When I look at the K31, unlike earlier versions, it is a front locking action and assuming it is properly heat treated and made of excellent materials, it should be as rigid and strong as any other military bolt rifle. In my opinion, the earlier rear locking versions are in the same class as Lee Enfields; not so strong.
I like the cartridge and think it was a better military design than the 30-06 for two reasons: It is shorter and the rim is thick. Both of these are advantages for automatic weapons, which would hardly been a consideration for the designers of the M1903 and the 30-06, but, in time, these two factors became primary reasons for going to the 7.62 Nato. If we had simply copied the 7.5 X 55 Swiss we could have avoided the conversion.
Over my chronograph I find Ball ammo pushes a 174 grain bullet just at 308 Win velocities, and my handloads pushed a 168 just a little faster without any pressure problems.
Code:
[SIZE="3"][B]7.5 x 55 Swiss Model K-31[/B]
AP11 Swiss Ball headstamp DA 78
24 Mar 04 T = 70 ° F
Ave Vel = 2565
Std Dev = 11
ES = 23
Low = 2551
High = 2574
N= 4
168 gr Nosler Match 51.0 gr AA4350 INDEP brass and primer OAL 2.850
22 Dec 01 T = 58 ° F
Ave Vel = 2536
Std Dev = 17
ES = 45
Low = 2510
High = 2555
N= 9
168 gr Nosler Match 52.0 gr AA4350 INDEP brass and primer OAL 2.850
22 Dec 01 T = 58 ° F
Ave Vel = 2624
Std Dev = 31
ES = 72
Low = 2588
High = 2660
N=5 [/SIZE]
The K31 is too complicated for a general issue rifle. I have been handed Mosin bolts to reassemble because the owner could not figure out how to put it back together, and one owner was a retired Army Officer. It is hard to believe but for some folks, door knobs are a complicated mechanical item, and rifles need to be as simple as possible for these people. A K31 bolt has too many parts and would totally confuse the mechanically challenged. The K31 is an expensive rifle to make. I took one to a gun designer friend of mine, he was examining it, saying “good”, “good”, and then he said: “this is an elliptical cut, I don’t know how they did that”. Based on his comments there were some very specialized machine operations to make K31’s and that would have been a disadvantage if the Swiss had to farm out work to small machine shops. After losing a number of Armies and all their equipment in Russia, the Germans learned the value of making rifles fast and cheap and the HK91 design reflects this. I do not believe the HK91 was meant to be rebuilt, rather the emphasis is to make mass quantities as quickly as possible. The K31 reflects an earlier era when rifles were built to last for 90 years, even though the average lifetime of an Infantryman in a major war is about 9 months.
Also heard one of the reasons why Hitler never invaded Switzerland was because all of their infantry was trained marksmen with the k31 at like 300 meters(might be 200, correct me on that if you know it.
I am certain that the actual reasons were far more complicated than this.
http://history-switzerland.geschichte-schweiz.ch/switzerland-second-world-war-ii.html In a contest between a Tiger tank, Stuka, the 88, and a K31, the Tiger, Stuka, and 88mm will win every time. It is my opinion that Hilter received more benefits by not invading Switzerland, than he would have received had he taken over the country. For the Swiss, they were lucky that Germany's resources were over stretched fighting England, Russia, and America, because there were German invasion plans.
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