Swiss K31: Stunning

sandwarrior

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My day at the range with my Swiss:
BBEFD865-8CB8-41AB-8FC0-F785586A783A.jpeg

that is at 100 yd. 5-shot group.
Conditions at the range:
BF7E955B-5C8F-41FA-B167-1C4304DA80B3.jpeg
 
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eicas

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I’ve been absent for a while. I really need to retire as this whole “work thing” is seriously cramping my hobby time.

Great shooting, guns and discussion! The last time I had mine out was mid-October. Worked on the RL17 and 175smk combo. Both the 175s and the 165gr PSPCL seem to enjoy a rather pokey 2250fps. It would be nice to up it a bit, although not sure how much I’d gain pushing say 2600/GP11 territory. I have to plug in the numbers past 300yds and see how much different the drop would be, and whether it’s worth the wear and tear on a 100+yr old gun. If I want to “launch ‘em” I’ll get the winmag.

Any particulars on that Privi loading would be appreciated!

I cannot say enough nice things about Swiss Products. The items and the support I’ve received from them has been exceptional.

I posted in another thread IIRC, but I’ll toss a few pics up here from October. Hopefully here soon, I’ll snowshoe out and have some more fun!
 

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sandwarrior

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I’ve been absent for a while. I really need to retire as this whole “work thing” is seriously cramping my hobby time.

Great shooting, guns and discussion! The last time I had mine out was mid-October. Worked on the RL17 and 175smk combo. Both the 175s and the 165gr PSPCL seem to enjoy a rather pokey 2250fps. It would be nice to up it a bit, although not sure how much I’d gain pushing say 2600/GP11 territory. I have to plug in the numbers past 300yds and see how much different the drop would be, and whether it’s worth the wear and tear on a 100+yr old gun. If I want to “launch ‘em” I’ll get the winmag.

Any particulars on that Privi loading would be appreciated!

I cannot say enough nice things about Swiss Products. The items and the support I’ve received from them has been exceptional.

I posted in another thread IIRC, but I’ll toss a few pics up here from October. Hopefully here soon, I’ll snowshoe out and have some more fun!
So I talked to zfk55sr and he said he uses 45.5 gr of RE-17 behind a 175 SMK loaded .002"-.004" off the lands. With these PPU Swiss bullet copies, you can't get to the lands in my rifle. So, I loaded them .010" under standard mag length of 3.090", so 3.080" My mag has a lot more room than that, so I think my cartridges are about .020" under mag length. Maybe it's tighter down in the bottom of the mag.

In any case, what I have for miscellaneous primers is magnum rifle. So, I loaded the RE-17 down to 44.5 gr. That load matches the sights as far as elevation goes. At least out to 400. I bumped the sights up one notch and didn't have to hold. That was in about 40 degree weather believe it or not. We had a heat wave and took our 100 inches of snow and made the piles about 1/4 the size they were in early December.

Added: I have to ask where you are. As your first pic looks like a major Montana highway with, of course, forest in the background.
 
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eicas

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Yep. I had the same problem with my 1911. The throat made my R700 5R look like it has tonsillitis. I barely touch the lands with the 175smk, and don’t have enough length to get good neck tension. I just tossed up my arms and loaded them to 2.410” CBTO. I used RL17 and did a spread from 43.0-46.0gr. I’ll attach part of that below. It did start to tighten up past about 45.5gr, so perhaps I will redo the upper end of that and even bump it past 46.0 a bit. Looking at my notes, I show about [email protected] with a temp in the upper 50’s. Issue is my eyes are 56yrs old with a bit of astigmatism and now farsightedness. Diopter sight not withstanding (those things rock!) I can never be sure if I’m “off the node” or just “off my prime”. Lol. I figure if it’s close to a Quarter, it’s good at 100yds at least.

Pics are from God’s Country Upper Peninsula of Michigan.
 

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sandwarrior

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Yep. I had the same problem with my 1911. The throat made my R700 5R look like it has tonsillitis. I barely touch the lands with the 175smk, and don’t have enough length to get good neck tension. I just tossed up my arms and loaded them to 2.410” CBTO. I used RL17 and did a spread from 43.0-46.0gr. I’ll attach part of that below. It did start to tighten up past about 45.5gr, so perhaps I will redo the upper end of that and even bump it past 46.0 a bit. Looking at my notes, I show about [email protected] with a temp in the upper 50’s. Issue is my eyes are 56yrs old with a bit of astigmatism and now farsightedness. Diopter sight not withstanding (those things rock!) I can never be sure if I’m “off the node” or just “off my prime”. Lol. I figure if it’s close to a Quarter, it’s good at 100yds at least.

Pics are from God’s Country Upper Peninsula of Michigan.
Nice groups. I have to say, it's me off my prime. I'm 56 too, and also in da UP. Hancock, right across da canal from Ho'-un. I shoot down in Baraga. It's the only range that stays open all winter up here. If I get all lined up with the rifle in the bags, I'll shoot pretty good. but sometimes, those sights wanna play tricks on me.
 

eicas

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Never been to the range there. Public? I have a spot off the deck at 100yds. I used to get about 170 but the trees grew. Lol I have access to a pasture down the road. Depending on where the cows are, I can get anywhere from 900 to about 1300yds. That’s the field in the pics. The other spot is off US2 near Watersmeet in the Ottawa National Forest. Easily a few miles space using pipeline right-of-way. That’s spring and fall only though due to high growth. Not permanent residents up dere yet. Soon. Just built a pole barn in October but the early cold in November kept me from pouring the slab. We should link up for a beer and a pasty!
 

sandwarrior

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Never been to the range there. Public? I have a spot off the deck at 100yds. I used to get about 170 but the trees grew. Lol I have access to a pasture down the road. Depending on where the cows are, I can get anywhere from 900 to about 1300yds. That’s the field in the pics. The other spot is off US2 near Watersmeet in the Ottawa National Forest. Easily a few miles space using pipeline right-of-way. That’s spring and fall only though due to high growth. Not permanent residents up dere yet. Soon. Just built a pole barn in October but the early cold in November kept me from pouring the slab. We should link up for a beer and a pasty!
We should, I'll bring some down from AMY J's Traditional Finn pasties. They'll still be hot by the time I get there, lol. When we moved up here in 2017, there was a bunch of farmland for sale around Bruce's Crossing. Not anymore.
 

zfk55sr

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Well gents, there's quite a bit to address on this one and I hope I'm not going to be too long-winded for you.
GP 11 is still available and this one is from one of my recent archives:

In Jan 2016 new production runs of GP11 production began. At the end of 2018 the quantity on hand will be approximately 130 million rounds. Production of the old GP11 ammunition stopped in about 1995. Until all of the reserves in Switzerland are gone, the new production will not come into the United States. It is already in Canada at some shooting clubs and is in the shooting clubs in Switzerland already. The only difference between the old GP 11 and the new GP 11 is that there is no wax ring, and that wax ring is not a lubricant but a storage measure. The ammunition is still crimped but is less of a rolled crimp and more of a taper press crimp. Unfortunately, the new run is not Boxer. It still Berdan primed.

As for brass, this is my own archived explanation:

The k31 and it's mates, the 1911, k11 and the rare (in the US) zfk55 Swiss Sniper Rifle are a rarity in another category. A Military series of rifles rifles designed around a specific cartridge for accuracy and performance.

The intent of this cartridge/rifle mating was to hit a human in the kill zone at range and they performed as intended. Not many production rifles are capable of doing that. The very great majority of these rifles perform as intended.

Are there rifles that outperform it? Of course there are, but none of them are a standard military issue firearm designed around a dedicated production cartridge for that rifle.

The GP11 cartridge.
The k31 and it's mates, the 1911, k11 and the rare (in the US) zfk55 Swiss Sniper Rifle are a rarity in another category. A Military series of rifles rifles designed around a specific cartridge for accuracy and performance.
The intent of this cartridge/rifle mating was to hit a human in the kill zone at range and they performed as intended. Not many production rifles are capable of doing that. The very great majority of these rifles perform as intended.
Are there rifles that outperform it? Of course there are, but none of them are a standard military issue firearm designed around a dedicated production cartridge for that rifle.
There is nothing wrong with what reloaders attempt to do, but considering the GP11 cartridge was the "beginning", why all the dancing around cartridge profiles? It's common knowledge that 1911s and k31s perform at their best with the ogive no more than a couple of thousandths off the lands/grooves. Neck tension IS a rather large factor for repeatability. There is a world of difference between neck crimping performed by us reloaders, and the Swiss (RUAG) factory cartridge crimping new brass.
And a group is not three rounds. I consider a great 3 round group as "a fortuitous group."
A group is a 5 round minimum.
When we consider a particular set of load data as "proven", it means a 10 target minimum (typically 20 for us) with absolutely "repeatable" 5 round POI groups per target. That data is then assigned to that rifle by serial number in a small log book that each rifle here has.
If that data works well with another 4 or 5 rifles, then it's logged into our main Data Book for k31s.
My "data" on the www.swissproductsusa.com site is a fraction of a highly condensed series of many thousands of rounds of data testing over a 35 years +/- period of time. All that means is that the data presented worked as written for a small group of load testing rifles. ALL of the data was collected from rifles fired from a fixed "Accurite" firing device. Only the trigger finger touched the rifle at all, so the human equation was removed altogether.
For "us", (son( Latigo and me, the reloading process for the 7.5x55 (and the .308s) has been cast in stone for quite some time. That does NOT mean that you can't arrive at the same success by your own preferred reloading methodology. There is no "one way" to success. If your method produces great, repeatable results, who's to argue your process? Remember,
Omnes viae Romam ducunt.
*All roads lead to Rome*

RUAG Boxer Swiss National Match brass......... the finest on the planet.
Ok. So here's how the American reloading part of it began for the k31, the G11's, the zfk55 and the Pe57. I don't remember the year, sometime in the 90's but a lot of shooters on the various Swiss Forums and elsewhere will remember better than I do because they bought it from me.......... My memory has gotten terrible......We brought in some 10,000 Ruag Swiss National Match Brass, but before that, I called Grafs and three other outfits asking if they'd like to front this buy and handle it themselves. "What? 7.5x what? For what rifles? never heard of them"..... So....... we brought it in.

Within two weeks the whole bunch was gone. I called Grafs again. "What?!? You sold it all already?" Yep...... and I'm about to bring in another 50,000 of the same brass, and another 150,000 as soon as that's gone. I expect about a month. "Wait, wait wait! Do you want us to handle that?" I put them in direct touch with Ruag in Bern, and......... that's how it all began for US reloaders. I have an awful lot of Norma brass here, but if you really do a lot of reloading, you already know how soft Norma brass is.

I can't remember how much RUAG brass we have, but if you anneal every 5 cycles, you're going to be working on that first 200 brass for an awfully long time. I have yet to have any RUAG brass fail on me, and you can guess how many rounds I've sent down range here over the past 18 or 20 years since we did that first import............ That incredible boxer brass was cut off for export maybe 10 years ago when RUAG began their Commercial Loads for sales to Europe. Can't remember for sure , but that's when Grafs began working with PRVI Partisan for brass and loaded cartridges and our own 18 year association with Graf's began.

Now the last reserves run of GP11 in 1995 are nearly gone, but RUAG began a new run two years ago. It's still that great Swiss National Match brass and still labeled GP11, but it's also still Berdan primed. The wax ring is gone since log term storage is no longer necessary. The last firearm in the Swiss Army requiring the crimp is the MG51, and that will very soon be replaced by the FN Minimi, so........ no crimp required for the 7.5x55 caliber with all the select mode rifles no longer in service.

As for reloading, we have equaled and surpassed the repeatable accuracy of the GP11 many times over. There is no magic. For the past five years we have exclusively used Reloder 17 imported by Alliant and manufactured in the same munitions house as the original GP11 began in the 1800s. The only difference between then and now is that sometime in the mid-70s the clock inland formula was changed for a better burn rate. Reloder 1 was developed by the Swiss for its consistent performance across a very broad temperature spectrum, from the coldest to the hottest temperatures.

Projectile weight most effective with that powder is from the 168 to the 190gr projectile with the 175 showing the most consistency. The projectile match for the GP 11 is the burger 175VLD, but unless you have deep pockets you may want to use the Hoprnady 175 ELD. The results very closely mimic GP11 performance.

As for current available brass, pervy partisan does make 7.5 x 55 brass as does Norma. You will find that the 184 brass will work perfectly in your K 31 but is much better suited to the 1911 series of rifles. The reason I say that is that the rim on the 184 is thinner than that of the 7.5 x 55 case and you may experience an extraction failure in 1 out of 10 or 15 cycles in a K 31. Extraction of that case from the 1911 series is 100%.

This is getting a bit long-winded so I would like to continue on dies for our caliber at a later point in time. I hope this did clarify a few of the things that I read in this thread.

New production GP11 box & cartridge.

 

steve123

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I wish someone had a jig that we could buy to use to drill out the Berdan primed GP11 brass! Or send the brass off to an outfit to have it done.

I tried the hydraulic method and it was a mess. I didn't mind using the Berdan primers.
 
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zfk55sr

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There is. I think there's a video and also a tool for sale. I saw it a couple of months ago so I'll go see if I can find it again.
I have a berdan decapping tool here of the handheld variety, but one of the die makers also makes a decamping tool for your press.
I'll see what I can find and get back to you
 
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DJL2

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I've tried, unsuccessfully, to make my own sight tool. Short of asking my Father-in-Law to bring one over this spring, does anyone have a lead on a K31 front sight tool for ~$50 (equivalent to the Euro cost, but with a less convoluted delivery)?

I monkeyed with the sights, because I'm dumb sometimes, and need to get things back to where they ought to be.

I wish the inexpensive K31 were still out there...would love to get a second to make it less burdesome when I do what I usually do to things that ought to be left alone.
 

DJL2

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Yeah, I'm like 15 bucks in on a nut splitter and bits that haven't done the job. Likely a problem with my parts selection. I'm not inclined to keep throwing money at the DIY version when $50 and patience will get me the real deal. My K31 will just continue to enhance the gun safe.
 

sandwarrior

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Or, you can figure out the adjustment mathematically and move it to that point with a $2.99 c-clamp and a woodruff key?????
 

Davo308

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Just for the heck of it, I thought you guys might be interested in seeing the new LHO, or left-hand operating system for the K 31s.View attachment 7630556
Does this work with the excellent Swiss Products clamp on scope mount?

I have a good friend who is left handed, he's already drawn to my k31s because of the straight pull, but I think this might push him over the edge to get one himself.
 

zfk55sr

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Added to my reloading page on our website after current, extensive load data collecting:
Reloder 17.... 51.5 gr under either the Berger VLD or the Hornady 175gr ELD.
As is usual, please begin to grains under and work up.
Reload safely, gents and good shooting.
Please remember that 95% of your accuracy is going to be in correct case preparation.
 

Davo308

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Added to my reloading page on our website after current, extensive load data collecting:
Reloder 17.... 51.5 gr under either the Berger VLD or the Hornady 175gr ELD.
As is usual, please begin to grains under and work up.
Reload safely, gents and good shooting.
Please remember that 95% of your accuracy is going to be in correct case preparation.

Thanks for the info, does that approximate gp11 velocity?

Also have you tried Sierra new 169 grain projectile?
 

zfk55sr

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The measured velocity is 2450 FPS.
We have not tried the new Sierra simply because we only use the 175 grain projectiles.
If you're going to a lighter projectile you will want to rework your powder volume.
On the opening page of our website, in the upper right-hand corner is a link titled "rifle info". Click on that and scroll down to the pertinent subject matter title. There are 55 years of my archives on Swiss rifles contained in that section.
www.swissproductsusa.com
 

AManWearingAHat

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I beg to differ on the reloading. Using the correct power, dies, and bullets you can certainly match and surpass GP11. Reloader 17 and properly prepared cases make these rifles sing.

Highly recommend a set of the original Swiss Diopter sights for these if you can find them. They make the rifle a hoot to shoot.
 

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zfk55sr

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There are no "original Swiss diopters". Every single one of them coming out of Switzerland and Germany were aftermarket made by cottage industries around Bern. Some were supplied to BERN but they were never, ever an issue item to Swiss soldiers. We began making ours 21 years ago and after submitting to the SSV, they were accepted by the Swiss SSV as being sanctioned for any and all Swiss matches worldwide.


The image represents an entire repeatable target using the information contained within our website. 5 rounds at 150 yards on the SP range in Lost Prairie Montana. The load data is contained within the appropriate title on our website
 

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zfk55sr

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I posted this just this morning on another forum. Of follow-up with an explanation because this thread is not particularly active and if you are really into Swiss rifles, it's worth giving it a read.
--------------------------------------------------------------

Pierre St. Marie
Philip Kinscherf I'm sorry I missed this one. We believe that case preparation is 95% of the successful formula. I don't typically like to post load data, and on our website there is a disclaimer but I'm not sure if that's even legal on an open forum. I'll give you this disclaimer anyway.
-------------------------------------------
Swiss products cannot be held liable for the use or misuse of the following load data. The rifles for which this load data is intended are in the curio and relic category, and as they are aged rifles there may be mechanical or metallurgic idiosyncrasies that cannot be foretold. The reloader is advised to begin two grains lower than the posted accuracy amount.
---------------------------------------------
So, all that being said, bear in mind our case prep section on our website is very important for this load data to succeed in your rifle. This is one we developed some 15 years ago after we discovered that the powder itself was manufactured in the same munitions plant that has always supplied powders to RUAG.
This powder is imported into the United States from Switzerland by Alliant with their designation being "Reloder 17." With correctly prepared brass, we use a 175 grain Berger VLD over 51.5gr of RE17. You're going to be pushing right at the threshold of 2500 FPS.
You will find other powders and projectiles listed in the appropriate title in the link at the upper right hand corner of her opening page entitled "rifle info".
Begin a bit lower, and please reload safely.

 
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AManWearingAHat

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sorry, I didn’t mean to imply originally military issued diopters. I was referring to the aftermarket ones commonly used by Swiss Civilian target shooters that install on the receiver and over the front sight.

In fact, I think I got my digital copy of the manual from my set from you on another forum.
 

MarshallDodge

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I wish I bought the four I saw on the rack at Big 5 for $99 each back in 2006. I was in the middle of a move and by the time I settled in, the secret of the K-31 was out.

I did end up with one eventually and need to get out and shoot it more 😎
 

Davo308

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There is more than you would suspect in proper case preparation for precision shooting, and if anyone here is interested, I can certainly post it. I've always liked this thread and I'd like to see it become active again.

I'd love love love to hear more about it.

The fact that a design from the early 30s and prior is STILL excellent is so cool.
 
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zfk55sr

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I can't believe I forgot about this, but I suppose it's just OGS catching up with me again.
You'd better grab a beer and some popcorn. This one is not particularly short.
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Advanced case prep,

There are two directions the reloader for the Swiss 7.5x55 can take as concerns our approach. Assuming you've already read our initial approach, you may choose to end it there. This next step will take you into increasing accuracy and developing repeatable targets.

Case prep is, for us, easily 90% of the repeatable round process. From here on you'll need a Chronograph. It's the only way to measure your success in the reloading process. The term "Standard Deviation +or -" (SD) means the difference between your fastest and slowest round fired. That deviation is very dependent on the "neck tension" of your resized case, or, in other words, how tightly the neck grips the projectile when it passes through your bullet seater.

Two things will control that. The amount of the neck gripping the projectile, and how tightly the projectile is gripped. Both will greatly affect the SD, and the further downrange you shoot, the more critical that becomes.
Remember that we're talking about our caliber only. Other calibers will behave differently and will require or allow far more variables because of the short throated chamber of the k31. Yes, I'm well aware of the 911 series being a bit different in the throat, but also keep in mind that the GP11 cartridge was developed in Bern for ALL of the Swiss rifles (save the 1889 and earlier) from the G11 right through the MG51..... All using the identical cartridge, and all with the very accurate end result for a production military issue cartridge.
The first control of neck tension will be, after full length resizing, trimming to an absolutely identical length. This will control the amount/length of the case neck gripping the projectile. If you've already bought your press and dies, this might be as far as you want to take it..... But if you're going to the next logical step in controlling neck tension, you'll buy a set of Redding Comp dies.

This will allow you to full length size (FLS) the case body and resize the neck seperately. Why? Because using a Redding collet, you can assure that the neck tension is as uniform as possible throught this step. You may want to buy two collets...... One at your known caliber size and one the next size down. Only seating the projectile is going to determine which one suits your particular projectile factual size.
"Aren't they all identical? No. From Mfg. to Mfg. there can be a difference so slight that simple measuring might not show any real difference. All Sierra's may be the same, but switch to Berger or Hornady or any otehrs may not be absolutely identical, and with neck tensions, we require identical performance. Nit picking"? Maybe, but your long range targets are going to tell you.
Ok. Now you have your basic procedure. The next step for the most devoted is Case Neck Truing.
---------------------------------------------------------------------------------
Tension as in "neck tension" has an incredible amount of importance in reloading.
Neck tension is controlled by two things, those being case neck trimming and truing.
Case neck trimming will determine how much of the inside surface of the neck is going to grip your projectile. Neck truing will determine how equal the neck tension is on the full 360° inside of your case neck. This is not going to be a tutorial on truing as there are a large number of videos on YouTube explaining exactly how you do it. I'm simply going to give you the importance of these two functions.

There are a plethora of case neck trimmers on the market, and not all of them function perfectly every time. If you have the kind of trimmer like the old standard RCBS, you have to tighten the collet around the base on each individual case. That actually does leave room for barely noticeable differences, but those differences do affect the grip on the projectile. The shorter the case neck, the less of a grip there is on the projectile just as the adverse is true. Shorter or longer, the true case length is very important. Every projectile that you reload should have the same neck length right to the thousandth or less.
So other than correct length sizing in your dies, you might think all you need from that point is a bushing, and rightfully so. When we are setting up a new caliber, we typically order three bushings. One in the recommended diameter, 1000th smaller, and one the next size up. We don't always end up using the recommended bushing, and we will reload 20 rounds using each bushing and let the target show us which bushing is correct. That is usually the end of the line for most reloaders. The exact neck tension might be correct on some of the cases and not absolutely correct on others. All of them are going to be the same outside diameter for sure if you trimmed to length correctly and have selected the best bushing for accuracy for that particular case and projectile. But there is one thing that is not addressed.

Let's consider that we are going to check a box of 100 brand-new cases from Norma, Lapua and Hornady, all of them listed as "national match brass". All things being equal, those cases should be absolutely identical inside and out, but are they factually identical? All cases, new or not should be sized on your own dies and the cartridge length trimmed to what you know is correct for your caliber and projectile. You never assume their virgin brass is ready for you to reload. So, you've done those first procedures and maybe even weigh them to check that they are all similar in weight, and most likely they are. You determine the correct bushing, do comparative loads to determine which is really the correct size and once that's done, were ready to go, right?

"Not so fast there, Potrzbie". There's one thing that you still have not determined that is also something that many reloaders never consider. The case wall thickness of your neck. In virgin national match brass, you would expect it all to be identical, but is it really? Most, or all of it might be for that particular run of brass. But as with all machinery, when it's time to set up the new tooling that means that there has been wear somewhere in the system. Look at the first illustration and you will see what is commonly found in standard brass. National match brass "should" be perfectly concentric, but you will find it is not always so. "So what? The bushing should take care of that". Actually it does not. It makes sure that the outside diameter in relation to the projectile is perfect but if the brass is thinner on one side than the other, does that affect accuracy? Absolutely!
case wallmeter.png

The "perfect system" is going to be a coaxial press that aligns absolutely everything on the case head, from the bottom all the way to the tip of the projectile. If you expect everything to be concentric for maximum performance downrange then you must include the inside of the neck also being concentric to everything else right from the start. If it's not, a very slight bit of tension will happen when a coaxial press, or any other for that matter, cycles up to align everything. The case neck without Concentricty is going to actually apply more pressure to one side of the projectile than the other with its grip. The only way to change that is to true the case neck. It can be done one of two ways and the easiest is to remove brass from the outside of the case neck. When the entire cartridge is forced up into the die the case neck will also be aligned.

That's far more of a PITA. Than doing the outside, and the fact is that doing the outside is enough. What the little digital meter will tell you is by turning the case neck that is contained within a pilot mandril will give you a reading of thinnest side of the neck because the meter sensor will be pushed out at the thickest point. The lesser reading is the one that you will use for adjusting the cutting tool. From that point on, it's a very simple matter of using a 21st-century case neck truing system. I'm providing you with a couple pictures of the (in our opinion) combination that will take you to that point..

One is the Wilson case trimmer and the second is the mini lathe from 21st century. There's not a lot of dollars involved in this and if you're doing long-range precision shooting, this process is a must.
As I said, I'm not going to give you a tutorial here on how to use both of them because there are enough videos on YouTube to show you exactly how to do that without me explaining for the 20th time something others have already done. A complete tutorial will eventually end up in our "rifle info" section on the opening page of our website.
 

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Deej

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I’m going to have to dig out my reloads from the 90’s and see what I ended up with and probably redo them. Thanks for all the info and the walk down memory lane.
 
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Ledzep

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    Hammer bite is real. It does shoot extremely well, though. I was pretty reliably able to go 6/8 or 7/8 on a 12" triangle plate at 100yd. A 12" square or torso target would be easily 8/8.

    Smoothest slide/frame fit of anything I've ever owned or handled. Trigger is a touch heavier than my CZ shadow 2, but it is CRISP! Hammer bite and magazine capacity are the only downers. Wish they still made stuff like this...


    KIMG2696.JPG


    KIMG2694.JPG
     

    ptosis

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    Hammer bite is real. [...]
    Wyss Waffen in Switzerland, Karl Nill in Germany (and a few others) used to manufacture add-on beavertails, just to fix this.

    There are two kinds: one with a hole, for the screw which holds the trigger group on -6 models, and the plain one, which goes on military -2 models (which you seem to have), which is simply epoxy-glued on the handle. Holed models can be glued as well on any P210 model.

    I have one, and it works as intended.

    Another solution is to simply nail off a part of the hammer, but I always considered it a crime with such beauties.

    EDIT: P210-6S or P210-6 Heavy Frame models do have longer tails from factory, and do not require any add-ons to prevent hammer bite.
     
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    Ledzep

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    I have a wood stock project, then some other wood projects in line first... but after those I may put my 3d modeling skills to the test to see if I can print some grips that don't put so much meat in the way of the hammer. I feel dirty about thinking about modifying this at all. :)
     

    ptosis

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    I have a wood stock project, then some other wood projects in line first... but after those I may put my 3d modeling skills to the test to see if I can print some grips that don't put so much meat in the way of the hammer. I feel dirty about thinking about modifying this at all. :)

    Back in the old days, when Facebook did not yet grow into the monster which ate us all, a few people on a French-speaking Swiss guns forum have tried that: https://www.feulibre.com/t11247p50-beavertail-pour-un-p210
    (see also the following pages, there are bits of STL available for download, if it helps)

    1634893188487.png


    1634893254176.png


    Apparently it worked out rather well, even with hobbyist 3D printing technologies from 10 years ago.
     
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    kujuak

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    Anyone using Vihtavuori N140 or Varget to load for their K31?Anyone ever try Berger 185gr Juggernauts in their K31?
     

    sandwarrior

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    Yes, and yes.

    N140 works just fine. However, you leave a lot of room in the case and that ...~generally~... affects accuracy on the negative side. Unless you are into serious competition with these, it is a non issue. The rifle will shoot these quite accurately.
    Starting load for VV140 is 36 gr. behind a 185. Work up a ladder and STOP when you get good consistency. Working loads up hot in a K31 does not work well with any powder/bullet combo.

    The Berger 185 Jug is a good bullet in the K31 if you don't work up hot. It won't 'match' your sights all the way out, but that is most aftermarket bullets with the K-31. So, shoot it enough and note the differences in sight height and POI.

    Good luck, as we mentioned above these are great rifles.
     
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    ptosis

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    Judging by the BC numbers, Hornady ELD-M 178 should be the best match for the 1980s-1990s production GP11. This said, the GP11 projectile undergone several changes since its introduction in 1911, and the K31 iron sights beyond 600m or so do not match it very well neither.
     
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    Ledzep

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    Hopes and prayers for my wallet. It will be a long road to recovery...
    zfk.jpg


    I don't know if this is common (From what I've seen of the rest of this stuff why not??), but I zeroed out the scope adjustments, slapped it on the rifle, and my first shots at 100 center punched the target. Very pleasant to shoot with the brake up there. Not obnoxiously loud, either.
     

    Ledzep

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    Zfk55 on the left, K31 on the right

    It may be hard to see in this pic but in person you can tell the lugs are clocked a little differently, and something interesting I don't remember ever having read/heard before is the addition of the 3rd rearward lug on the Zfk. Interesting to see the difference in length of the bolt bodies, too. It's a little funny how the "same" action tilted 15 degrees or whatever it was results in almost complete interchangeability failure.
    268334377_231341009077127_2670851034468557009_n.jpg
     
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    Davo308

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    Zfk55 on the left, K31 on the right

    It may be hard to see in this pic but in person you can tell the lugs are clocked a little differently, and something interesting I don't remember ever having read/heard before is the addition of the 3rd rearward lug on the Zfk. Interesting to see the difference in length of the bolt bodies, too. It's a little funny how the "same" action tilted 15 degrees or whatever it was results in almost complete interchangeability failure.
    View attachment 7765224

    Interesting I thought the charging handle was one of the few parts the k31 had in common with theZfk.
     

    Ledzep

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    I think they may physically work, but the Zfk handle is bent to level things out so if they were swapped the 'knob' would sit at an angle. I'll try it tomorrow.

    268593677_418849913354460_8138047267673504269_n.jpg
     
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    Tempest 455

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    Years ago I disassembled 10 rounds of GP11. Measured bullet weight, ogive, powder charge. case, overall weight, neck concentricity etc.

    For mass produced ammo, it's darn near a hand load in consistency. At least the lot that I measured. Pretty impressive as it's typically referred to as "surplus".
     
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