K31 - Bolt not fully seating?

idkwhativebeentold

Private
Minuteman
Dec 7, 2012
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42
Lakeland, FL
I noticed while greasing the bolt on my K31 that when it's
fully forward the back face of the bolt isn't entirely flush with the action.
The bolt turns fully and appears to lock with the serial number facing directly upward.

Is this abnormal or dangerous? I just picked up a couple of cases of GP11
and was planning on shooting this weekend.

I appreciate any opinions!
 

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If the serial number is at 12 o'clock you are good.

I've got a case of GP11 inbound as well, need to do a good re cleaning and find a suitable scope now.
 
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I just ordered the Burris XTR II 4-20x50mm.
Really wanted a high end scope but I just bought the 600rds of GP11 that left me a little light.
Trying to figure out what height and MOA setting for the rings based on the Bad Ace mount.
I emailed the company hopefully they can offer up some info.
 
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I just ordered the Burris XTR II 4-20x50mm.
Really wanted a high end scope but I just bought the 600rds of GP11 that left me a little light.
Trying to figure out what height and MOA setting for the rings based on the Bad Ace mount.
I emailed the company hopefully they can offer up some info.

I have the clamp on offset mount. Im looking for a Bushnell elite 3210 10x, or a Weaver Grand Slam tactical 3-10x but am not having much luck.

Im also considering the clamp on muzzle brake.

Hoping to be able stretch its legs.
15414442687552-1-768x480.jpg




This was my setup from about 15 years back.
100_1544_zpsosn0sa46.jpg
 
I have the Bad Ace mount, it pins to the rear sight base and screw into an insert you tap into it. Very solid it seems.
Where is that range? I wish we had access to ranges like that. Over here you have to join a club to shoot from 100-300 meters.
 
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I have the Bad Ace mount, it pins to the rear sight base and screw into an insert you tap into it. Very solid it seems.
Where is that range? I wish we had access to ranges like that. Over here you have to join a club to shoot from 100-300 meters.

Southern California. I usually shoot in the desert, but I don't have many steel targets.

I've heard good things about that mount, is that the one with the shell deflector?

Are you going to free float your barrel? Im going to try spacing the hand-guard to see how that goes.
 
It's got the deflector. I think I'll see how it shoots first.
I'm trying to keep it from being permanently altered.

What height scope rings did you use on yours?
Which MOA option? 0, 20 etc?


For mine I used mediums. Thats why Im looking for no more than a 40mm objective scope. It allowed the scope to be mounted low, but not so much that it interfered with with stipper clips or using the open sights.

Cant use a MOA option because I shoot with the offset scope canted over bore. Sounds odd but its comfortable and it functions well.

How often to you plan to shoot beyond 100 yards?

What is your scopes total elevation?


96gq4g.gif
 
Nice chart, that is extremely helpful! I plan to do it as often as possible.
This means either leaving the state of Florida, or joining a gun club, of which there are a few
that have up to 300 yards. I'm going to need to take a mini vacation else where to really test it out for real.
The 300 yards is nothing to this rifle, I was getting within 1 inch groups on the irons at 100 yards the first time I shot it.
 
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The attachment is the setup virtually all of us here at SP use. It's a fixed 6 power and goes easily to 500 yards and beyond.
The offset of the mount is 11/16", so leave it at exactly that POI at 100 yards and it will remain so out to 1,000 yards. No need to zero it on the bullseye. If you can tell the difference beyond 200 yards, you're a much better shot than I am, Gunga Dihn. LOL
Swiss Products Offset Mount.JPG


For A complete explanation, go here............. https://www.swissproductsusa.com/faq Scroll down to the "Offset Mount Sighting"
 
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I have the clamp on offset mount. Im looking for a Bushnell elite 3210 10x, or a Weaver Grand Slam tactical 3-10x but am not having much luck.

Im also considering the clamp on muzzle brake.

Hoping to be able stretch its legs.
15414442687552-1-768x480.jpg




This was my setup from about 15 years back.
View attachment 7125745

That looks like one of our Scope Mounts........... and the offset is less than the M1D Garand offset, but zeroed the same way.
 
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Nice chart, that is extremely helpful! I plan to do it as often as possible.
This means either leaving the state of Florida, or joining a gun club, of which there are a few
that have up to 300 yards. I'm going to need to take a mini vacation else where to really test it out for real.
The 300 yards is nothing to this rifle, I was getting within 1 inch groups on the irons at 100 yards the first time I shot it.


There is at least one place that goes out to 1K...



A 20 MOA scope base would be a good idea for 1K.
 
Davo308, as long as the scope itself has enough elevation moa, you should be good anyway. Many of them do.
The attachment is my zfk55 Swiss Sniper with a 10x IOR Valdada and it has enough for 2,000 yards.
Our Swiss Products field testing range is 500 yards. For 1,000 we just go into the pasture next door, but 500 tells us most everything we need to know.
 

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What is your preferred scope for the clamp on mount, for steel out to 800 yards or so?

I know a 1 inch tube is the way to go, but there aren't a whole lot of compact scopes out there in that size range Im seeing.

I liked the Bushnell 10x because it tracked well and optics were satisfactory.

I was informed here at the forum about the weaver grand slam tactical 3.5-10x.
 
Davo308, I haven't bought a scope in a very long time. There are a dozen of more scopes here in the armoury, and my own favorite scope is a very rare fixed 8 power. Both of those scopes you've named are well made and would serve your purpose. My own feeling is to use the one with the smallest objective lens. "The lower and closer to the axis of the bore, the better".
 
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I went with the Burris XTR II 4-20x50, and Vortex Precision Matched rings, 1.10"
That has I believe 90 MOA of adjustment. Pretty sure this combo will work.
@Davo308, that's Manatee in Orlando? Did not know they have that kind of range there.

Says its orlando, I just googled 1000 yard range Florida.

That scope should have the elevation required, according to the drop charts I've seen for GP11.
 
Here it is after the install and case purchse. Can't wait to dial this baby in. I checked out the gun club, man you have to jump through some hoops to get in there. I wish there was a public range over 100 yards, but I guess it's time to just give in and join the club.
 

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Here it is after the install and case purchse. Can't wait to dial this baby in. I checked out the gun club, man you have to jump through some hoops to get in there. I wish there was a public range over 100 yards, but I guess it's time to just give in and join the club.

That is looking like a sharp setup there!

Even at 100 yards there is plenty to investigate like how the action/tang screws impact groups and how tightly to clamp the forward barrel band.

I plant to do a deep cleaning and try some lithium grease before I take mine out again. (its balls hot here)

The GP-11 I ordered from Edelweiss came in this week, its from 1992. My last case was 1978 and I still have 60 or so rounds of that.
 
If I may......... From my Archives:

Accurizing Your Swiss Rifle
by
Pierre St. Marie

I am not at all concerned with the built in accurizing technique of pre-loading the stock. It is now my belief that this accurizing technique from the manufacturer leaves too many variables in the mix. Any flexing of the stock (being in direct, tight contact with the barrel) will change POI at range. If ALL users of the k31 & 1911 were to shoot their rifles with the identical technique, EVERY time, I may not have an argument concerning the armory shim/pre-loading methodology. But............none of us do shoot identically other than those in the shooting clubs, and, I suspect, even those good folks introduce physical variables of their own at times. So...............

I've invested quite a bit of time in arriving at a rather simple conclusion I had always known, from experience, to be true. "Do not interfere with the barrel". That simple. Of course, none of us want to remove that classic stock and fore grip from the Schmidt Rubins, so I did the next best thing. I relieved all reasonable stress contact from the barrel.

I did this by designing a "spacer" meant to go between the flanges of both barrel bands. This simple spacer relieved the barrel of any meaningful contact with the stock. If the spacers are used correctly, the fore stock will feel "loose" at the barrel band. Of course, one could rout out the raceway to relieve the barrel, but I am loathe to remove any wood from the stock. Allowing the barrel to vibrate uninhibited definitely tightened up my groups. I had, of course, used a load capable of moa for these tests. This also meant that I could not use the sling in any kind of a bracing action. That would negate my efforts. Now for the second discovery. I found that "balancing" the tang screw against the receiver screw also had an effect on accuracy.
To determine spacer width requirements, loosen the screw on the front band until the band retainer will compress and release freely. The space you see between the flanges approximates the thickness required for the spacer. With the spacer(s) installed, the front to the stock should have a bit of "play", so that you can see/feel it move when you wiggle it. The rear band should also NOT grip the stock tightly. It, too should have a bit of play. This will leave the barrel relatively uninhibited by the stock. Also remember not to use the sling to "brace" the rifle. That tension will put pressure against the barrel too. Use the sling just to "steady" the rifle without undue pressure.
After installing the spacers, I begin by loosening both screws. I coat the rear screw with LocTite. I then tighten the receiver screw dead tight. I turn the tang screw down tight and back it our 3/4 of a turn or a little better. You'll need to have around 30 dependable loads ready for this test. Definitely do it from a bench rest, and if you have open sights, use a clearly defined target at no more than 75 yards.

Fire a group of 3 or 4 rounds. Tighten the tang screw in 1/8 turn increments, repeating the process and, using a new target for each run, note how the groups will spread or tighten to minor degrees. These differences will make themselves manifest at range. Once you find the "sweet spot" with the tang screw, allow it to sit while the LocTite cures.

This procedure will be all the more apparent with scoped rifles, but the Diopter and Willaims will also show clearly what a difference can be made. Emails from subscribers to this method have proven to me that this method definitely works. Why "fix something that ain't broke"?......... because mine have the capability to outperform the ones that "ain't broke". The rest is up to the shooter.

Something I forgot to add. The k31/55 barrel band does NOT compress the stock tightly against the barrel. At least mine doesn't. This, and the fact that the bipod is attached to the receiver, tells me that someone in the armory felt that the barrel should be uninhibited too.

Just so we have some reality into this.......... I've always said that there are many k31's that work very well with the preloaded stock, but the stock has to be an "as original issued" stable stock. Sometimes improper storage and simple age will cause a stock to apply pressure in the wrong direction, and those rifles are the main reason for our using spacers and screw balance to accurize our rifles. We never, ever remove wood.
Another possible way is to change the lug shim, but once again, if the stock puts pressure left or right on the barrel, then that may not help much. When I said that every rifle in the armoury is set up with his accurizing technique, that doesn't mean that yours must be. It's just like reloading. There are many ways to get to a great end result, not just this way. It works for us based on the stock/barrel relationship of our individual rifles.
Check your forestock. Is the blackened area only straight down on the bottom. or does is show an uneven area of dark wood to the left, right, off dead center or the upper foregrip? And don't forget that the flanges on the front ring must be tight and solid. The stock should not be flopping around when fired.
I strongly disagree with the notion that my method accurizing these Swiss rifles is a mistake. It depends entirely on the current stock/rifle relationship, and in the past 20 years I've proven that many times over right here in the SP armoury.
Do what works best for you, and it might be that your k31's preloaded stock is perfectly fine, but because of the age and storage of these rifles, I've found that to be a minor exception........ Not the rule, and an over the bore mount is never a good idea. Yeah, yeah... I've read all about "deflectors" and we already have a number of prototypes on a shelf in the shop. They never work 100% without denting that rather valuable RUAG or even Norma brass, and if it does not field test 100% for 100% of the time....... we won't manufacture it.
I thank you..... Leslie thanks you. Leslie Salt Co @1887
 
I have the clamp on offset mount. Im looking for a Bushnell elite 3210 10x, or a Weaver Grand Slam tactical 3-10x but am not having much luck.

Im also considering the clamp on muzzle brake.

Hoping to be able stretch its legs.
15414442687552-1-768x480.jpg




This was my setup from about 15 years back.
View attachment 7125745
re: "This was my setup from about 15 years back" --

And that was mine --
k31+a-sml.jpg


The young one is 9 years old now, and the K31 looks like this:

k31-in-chassis.jpg
 
For mine I used mediums. Thats why Im looking for no more than a 40mm objective scope. It allowed the scope to be mounted low, but not so much that it interfered with with stipper clips or using the open sights.

Cant use a MOA option because I shoot with the offset scope canted over bore. Sounds odd but its comfortable and it functions well.

How often to you plan to shoot beyond 100 yards?

What is your scopes total elevation?


View attachment 7125904
In ICAO 0 alt., total drop is about 14.3 mrad. So with a flat 0 MOA mount one would need at least twice as much elevation range in the scope to shoot at this distance.

At 1500m alt., to go to 1100m (reasonable max for consistent hits in good conditions) a S&B PMII 3-12x DT needs an inclined mount; 20 MOA or 6 mrad do just fine.

And, by the way, the ballistic performance of the GP11 bullet is much better than this.
BC G1 = 0.549, or BC G7 = 0.276
see, e.g. https://k31.ch/en/docs/ballistics/
 
So what are these flange spacers you speak of and where can I get them?

Rookie we've been talking about this this morning and though we do have them in stock the cost value of this is so low that we're no longer sure it's worth the shipping to even send them out. The only difference between them and a standard washer from the hardware store is the varying thicknesses that we've made. The inside diameter and outside diameter of all of them is identical with the thickness being the only difference. If you think you really want some of these, do your measurement first and then send it to me at the Armory email address m[email protected].
 
Rookie we've been talking about this this morning and though we do have them in stock the cost value of this is so low that we're no longer sure it's worth the shipping to even send them out. The only difference between them and a standard washer from the hardware store is the varying thicknesses that we've made. The inside diameter and outside diameter of all of them is identical with the thickness being the only difference. If you think you really want some of these, do your measurement first and then send it to me at the Armory email address m[email protected].

Are you aware of any photographs on the net of these spacers?
 
In ICAO 0 alt., total drop is about 14.3 mrad. So with a flat 0 MOA mount one would need at least twice as much elevation range in the scope to shoot at this distance.

At 1500m alt., to go to 1100m (reasonable max for consistent hits in good conditions) a S&B PMII 3-12x DT needs an inclined mount; 20 MOA or 6 mrad do just fine.

And, by the way, the ballistic performance of the GP11 bullet is much better than this.
BC G1 = 0.549, or BC G7 = 0.276
see, e.g. https://k31.ch/en/docs/ballistics/

I ended up finding both of these scopes inexpensively on the PX. Wish the Grand Slam had a bit more elevation.

Weaver Grand Slam Tactical 3-10x Mil/Mil 16 mils total elevation.

Bushnell elite 10x MOA, 85 MOA/24 mils total elevation.


Also, looks like you have used multiple clamp on brakes, any tips for the install?
 
Dave oh I don't know about the Internet but since I'm the one that manufactures them I got pictures here somewhere I'll find them in the post just a little while thank you

Appreciate it. I hear much discussion about them but haven't found images online.
 
I ended up finding both of these scopes inexpensively on the PX. Wish the Grand Slam had a bit more elevation.

Weaver Grand Slam Tactical 3-10x Mil/Mil 16 mils total elevation.

Bushnell elite 10x MOA, 85 MOA/24 mils total elevation.


Also, looks like you have used multiple clamp on brakes, any tips for the install?
re: scopes -- on a flat base without counter-aiming the first one would go approximately up to 700m, the second -- up to 900m (at sea level). Beyond that -- you'd have to aim higher.

re: brakes -- the one on the first (old) photo is a prototype piece produced long time ago by a local armourer shop in Geneva region. Pretty efficient, nicely done, looking übercool, but heavy as a dead donkey (almost 400 grams). Also, it was too big, and required sawing off the bayonet lug. Also, it has vents all around, and in dry weather it raised clouds of dust when shooting prone. It is basically a tool for true men, who are not afraid of weightlifting and who shoot standing. (But then again, true men like that do not need muzzle brakes).

The second is mine (this is full disclosure): [link edited out]
EDIT: I just realised I am violating the forum rule on "not posting links to off-site sales". Just google for "k31-xxi blitz muzzle brake" (sorry about that).
Thoroughly dissatisfied with the market offering, I ended up designing it and running production.
And, yes, it is 100% compatible with the original wooden stock and WF diopter sights.
 
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