Hi Guys:
I've got a tidbit that some of you might find mildly interesting.
First, I've another Swiss K31 in the barn. I'll post some photos in a little bit.
I wanted to ask a question in relation to K31's.
I have both GP11 ammo and hand loaded ammo for my K31's.
When reloading I use a Hornady comparator tool to set seating depth. I use the comparator tool to locate and specify how deep the bullet can travel before it hits the lands. The tool goes on your caliper and uses a interchangeable collet that uses the ogive of the bullet to determine bullet depth. With the tool you can set as far or close to the lands as you like. The special case for 7.5x55 Swiss has the back of the case threaded so the tool can be screwed on. The mouth is loose so a bullet can be put in the case and the bullet will slide easily. You put a chosen bullet in the case attached to the tool. You insert the case in the chamber, push the bullet forward and lock the tool down. Now you can pull it out and check the depth of the throat.
Ok, here's the question;
I check the depth with a 150 FMJ bullet and the reading says the bullet can't be seated more than 3.260 in. or a bullet to throat interference will occur. So I seat the bullet to 3.250 .in, now it's .010 .in off the lands. If the bullet is seated any more than 3.260 in. the bolt won't close, as expected.
Then I measure a GP11 round. It measures, with the tool, 3.325 in. .065 in. longer. So the bolt should not close, right? Remember the tool measures from the bullet ogive, not the tip, so all measurements made from the same arbitrary spot.
Obviously it does chamber the round easily though, it's Swiss ammo.
So how can that be
There is an answer.
Which brings us to a greater point.
Here's a few pics of a naked K31 revealing it's ingeniously simple, near perfect design.
I've got a tidbit that some of you might find mildly interesting.
First, I've another Swiss K31 in the barn. I'll post some photos in a little bit.
I wanted to ask a question in relation to K31's.
I have both GP11 ammo and hand loaded ammo for my K31's.
When reloading I use a Hornady comparator tool to set seating depth. I use the comparator tool to locate and specify how deep the bullet can travel before it hits the lands. The tool goes on your caliper and uses a interchangeable collet that uses the ogive of the bullet to determine bullet depth. With the tool you can set as far or close to the lands as you like. The special case for 7.5x55 Swiss has the back of the case threaded so the tool can be screwed on. The mouth is loose so a bullet can be put in the case and the bullet will slide easily. You put a chosen bullet in the case attached to the tool. You insert the case in the chamber, push the bullet forward and lock the tool down. Now you can pull it out and check the depth of the throat.
Ok, here's the question;
I check the depth with a 150 FMJ bullet and the reading says the bullet can't be seated more than 3.260 in. or a bullet to throat interference will occur. So I seat the bullet to 3.250 .in, now it's .010 .in off the lands. If the bullet is seated any more than 3.260 in. the bolt won't close, as expected.
Then I measure a GP11 round. It measures, with the tool, 3.325 in. .065 in. longer. So the bolt should not close, right? Remember the tool measures from the bullet ogive, not the tip, so all measurements made from the same arbitrary spot.
Obviously it does chamber the round easily though, it's Swiss ammo.
So how can that be
There is an answer.
Which brings us to a greater point.
Here's a few pics of a naked K31 revealing it's ingeniously simple, near perfect design.
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