7.5x55=?


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PT1911
September 6, 2009, 10:16 PM
So, I have been contemplating getting a K31 and realized I know little about the cartridge... rather than googling it and getting some generic info, I was hoping you guys/gals would be able to inform me of its performance and some possible comparisons to other cartridges... thank you in advance.

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longhorngunman
September 6, 2009, 10:21 PM
Similar to a .308 but usually slings a slightly heavier bullet. Good round

engravertom
September 6, 2009, 10:27 PM
The GP11 military ammo is very accurate. It is Berdan primed though.

You will love the K31.

take care,

Tom

jerkface11
September 6, 2009, 11:05 PM
It's just like a .308 but has a lower pressure rating however that's offset by slightly more case capacity.

Sam1911
September 7, 2009, 12:08 AM
It's right in between .300 Savage and .308 Win. A little closer to .308, though.

All the usual surplus GP11 is Berdan primed, but it is match-grade stuff. Super accurate.

Fortunately, there is plenty of reloadable 7.5 Swiss brass available now and you can use any .308 bullet you want.

While the rifles are usually amazingly accurate, and you may be tempted to use every accuracy trick in the book to get the best out of it, you should probably not neck-resize (only). Because of the straight-pull action and little camming force on chambering, full-length resizing will probably ensure easier feeding.

-Sam

Sunray
September 7, 2009, 02:16 AM
Start here. http://www.surplusrifle.com/swissk31/index.asp

nwilliams
September 7, 2009, 02:48 AM
7.5x55 is a near perfect round, as others pointed out even the mil surp stuff can be considered match quality. The Swiss don't fool around, the K31 chambered in 7.5x55 is a hell of a nice combination.

Shung
September 7, 2009, 06:43 AM
It's a pleasure reading these threads ;)

p85
September 7, 2009, 09:29 AM
for the OP.... 412.5 couldn't resist ;)

foudufoot
September 7, 2009, 05:50 PM
I'll second Sam1911's comment on GP11. It's match-grade stuff. This was shot out of my K31 Privatserie with S-type diopter at 100 yards.

SlamFire1
September 7, 2009, 05:55 PM
Swiss service ball just equals 308 White box match in a M1a. There is nothing wrong or weak with this round.

I conducted some load development for the 7.5 Swiss. I have never purchased Swiss ball, but a bud gave me a chance to shoot some across my screens.

AA4350 gave excellent accuracy and just about duplicates Ball velocities with 51.0 grains and a 168 Nosler Match bullet. As you can see 52.0 grains produced velocities over Ball, so I do not recommend that load. It is here for reference.


7.5 x 55 Swiss Model K-31

174 grain 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

PT1911
September 7, 2009, 05:55 PM
I am liking what I am reading...

guess I left myself open for that P 85.... fair enough...

any more input from the gun gurus at THR?

jkingrph
September 7, 2009, 09:07 PM
K-31's are great shooters but generally look very bad due to the beat up stocks.

My best shooter among the Swiss crowd, and they are all good, is a slightly older model of 1911. It is probably the much longer sight radius due to the longer barrel. Another bonus of these older models is that the stocks are usually not beaten up as with the K'3l.

Exposure
September 7, 2009, 09:13 PM
All K31 purists should look no further. :D

Here is my K31 that I refinished and fitted with a clamp on scope mount and Tasco 3-9X Varmint scope. This thing SHOOTS.

http://i22.photobucket.com/albums/b301/paulj1973/K31.jpg

As others have said performance of the 7.5X55 is nearly identical to the .308 Win. Reloading is a bit trickier as full length sizing is needed every time the case is fired. If not full length sized the cases become difficult/impossible to close the bolt on. Not a big deal once you have a little experience loading for this fine rifle.

Here is a pic that I never miss the chance to post. 168 SMK over 43 grains IMR 4064 at 100 yards. For a 56 year old rifle I think this level of accuracy is more than acceptable! In fact I am pretty proud of it.

http://i22.photobucket.com/albums/b301/paulj1973/K31tightgroup.jpg

I am currently in the process of working up a deer load for this Fall with 165 Nosler Ballistic Tips. So far accuracy is in the 2" range at 100 yards with velocity in the 2500 FPS area. I plan to get it a lot tighter than that, and hopefully I will have a pic of me with my lovely K31 beside a nice buck to show you all in a couple of months.

If you have the chance to buy a K31 don't hesitate, it is a fine rifle at a truly bargain price!

jpwilly
September 7, 2009, 10:08 PM
K-31's are great shooters but generally look very bad due to the beat up stocks.

The stocks can be cleaned up! Here's mine with clamp on scope mount and Alaskan Guide scope.

PT1911...jump in the waters fine!

http://i124.photobucket.com/albums/p38/jpwilly/102_6066.jpg

http://i124.photobucket.com/albums/p38/jpwilly/102_6070.jpg

MissouriCrowinMass
September 7, 2009, 10:30 PM
Shot one of mine today. Looking at some different loads. I'm am NOT a marksman as you can see - I'm 58 with not great eyesight. I'm sure that the rifle is better than this.

These were .284 Winchester Casings resized to 7.5x55 using Castor Oil as a lube. I've always read to full length size. AND it is critically important to test the ogive and OAL. You read posts of guys making their OAL's too long and they wonder what's wrong as the cartridge won't chamber? You take a Dremel and split the case mouth on a dummy round. Insert your bullet. You chamber it and carefully remove it to measure the actually OAL. You make the OAL for that bullet about 10/1,000 of an inch shorter for that particular rifle. Works great.

Good luck.

lionking
September 8, 2009, 08:09 PM
I had bought a 1911 a couple months ago for $200 off gunbroker and finally tested it a couple weeks ago.I also have a tiger striped walnut K31 that I hadn't tested on paper so I did so that day also.For my satisfaction I was satisfied with the results,others can achieve tighter groups than I did but the results were a decent group size for my abilities anyway.

I tested GP11 and Prvi Partizan ammo.PP ammo shifted a bit in area but not too bad compared to GP11.I don't know if doing the "bullet test" applies to Swiss rifles but in both the barrel swallowed up the bullet so I don't know how to gauge wear on a Swiss rifle but the bores are sparkling and great looking condition.Both rifles gave me 3inch 10 shot groups at 100yds rested on average.

click to enhance

http://i198.photobucket.com/albums/aa45/lionking_rocks/swiss%201911%202/th_029.jpg (http://s198.photobucket.com/albums/aa45/lionking_rocks/swiss%201911%202/?action=view&current=029.jpg)
http://i198.photobucket.com/albums/aa45/lionking_rocks/swiss%201911%202/th_028.jpg (http://s198.photobucket.com/albums/aa45/lionking_rocks/swiss%201911%202/?action=view&current=028.jpg)
http://i198.photobucket.com/albums/aa45/lionking_rocks/swiss%201911%202/th_0332.jpg (http://s198.photobucket.com/albums/aa45/lionking_rocks/swiss%201911%202/?action=view&current=0332.jpg)
http://i198.photobucket.com/albums/aa45/lionking_rocks/swiss%201911%202/th_031.jpg (http://s198.photobucket.com/albums/aa45/lionking_rocks/swiss%201911%202/?action=view&current=031.jpg)
http://i198.photobucket.com/albums/aa45/lionking_rocks/swiss%201911%202/th_0302.jpg (http://s198.photobucket.com/albums/aa45/lionking_rocks/swiss%201911%202/?action=view&current=0302.jpg)
http://i198.photobucket.com/albums/aa45/lionking_rocks/K31%20walnut%20striped/th_012.jpg (http://s198.photobucket.com/albums/aa45/lionking_rocks/K31%20walnut%20striped/?action=view&current=012.jpg)
http://i198.photobucket.com/albums/aa45/lionking_rocks/K31%20walnut%20striped/th_010.jpg (http://s198.photobucket.com/albums/aa45/lionking_rocks/K31%20walnut%20striped/?action=view&current=010.jpg)
http://i198.photobucket.com/albums/aa45/lionking_rocks/K31%20walnut%20striped/th_009.jpg (http://s198.photobucket.com/albums/aa45/lionking_rocks/K31%20walnut%20striped/?action=view&current=009.jpg)
http://i198.photobucket.com/albums/aa45/lionking_rocks/K31%20walnut%20striped/th_030.jpg (http://s198.photobucket.com/albums/aa45/lionking_rocks/K31%20walnut%20striped/?action=view&current=030.jpg)
http://i198.photobucket.com/albums/aa45/lionking_rocks/K31%20walnut%20striped/th_007.jpg (http://s198.photobucket.com/albums/aa45/lionking_rocks/K31%20walnut%20striped/?action=view&current=007.jpg)

P.B.Walsh
September 8, 2009, 08:21 PM
Ya'll are making me want an old milsurp!! :)

lionking
September 8, 2009, 08:35 PM
yeah P.B it is real easy to be overcome by the milsurp bug.:DWhile Garands,Enfields,Mausers and such can be capable of great accuracy the Swiss rifles seem to be the rule not a exception.They all seem to gave been taken care off internally although maybe dinged up outside.Other milsurp types can be hit or miss accuracy wise depending on condition and or restoring.The swiss rifles tend to be accurate as is.

Here is my other Walnut K31 and results I got last time I tried it.

http://i198.photobucket.com/albums/aa45/lionking_rocks/k31/103.jpg

engravertom
September 8, 2009, 08:35 PM
OK, if you are bringing the Infantry rifles into this, then that changes things a bit.

Those new to the Swiss rifles often begin with the K31. If you taste the Long rifles though, you are in big trouble! They are often very sweet shooters, very nice triggers, and easy to shoot. I prefer the 96/11 myself, as the buttplate fits me better than the 1911, and it seems to have a bit of a shorter reach to the trigger as opposed to the 1911.

If you are serious about playing with the 7.5X55, just go ahead and get one of the long rifles! You will be glad you did. However, there are more accessories being made for the K31, so if you want to scope it, etc, that may be the way to go. You will be somewhat poorer for missing out on shooting one of the Swiss Infantry rifles though...

In any case, enjoy!

Tom

lionking
September 8, 2009, 08:39 PM
and results from my beech K31 with a diopter sight.With the PP ammo is shot in a string but I think that was me because after a while that little peep started messing with my eyes.I shot with the rest and shouldered not with a sandbag in the rear.

http://i198.photobucket.com/albums/aa45/lionking_rocks/K31%20with%20diopter%20sight/014.jpg
http://i198.photobucket.com/albums/aa45/lionking_rocks/K31%20with%20diopter%20sight/005.jpg

lionking
September 8, 2009, 08:48 PM
engravertom,agreed.I like the feel of the long rifles over the K31 also.The new one I got posted above I dunno if that is a 96/11 or a 1911 but I like it specially for the price.

I'm not that much more accurate shooting it over a K31 but the feel and sights are better to me.

The pics I posted above are just flat out results I got while testing them,I am sure if I shot them enough I would come up with a best of group smaller than what I got but all in all definately accurate milsurp rifles.

engravertom
September 8, 2009, 08:55 PM
96/11= spliced on pistol grip, 1911, the pg is integral to the stock. 96/11s were converted from 89/96s, which originally had the 12 round mag like the 1889,as well as the straight grip stock. When the 1911 came out, the Swiss decided to refurb the 89/96, by replacing the barrels to the new 1911 type barrel, and adapting them to the newer 6 round mags, and by adding the pistol grip to the stock. It looks like you have two different long rifles? You should be able to see the joint on the pg of the 96/11, and if you set it next to a 1911, the buttplates will have some differences also. IIRC, 96/11s typically have sn's under 300,000 or so.

I sure miss mine!

Tom

lionking
September 8, 2009, 09:06 PM
Tom sounds to me that my new one up above is a 96/11 because it has a spliced heal on it.I do have a 1911 also pictured here

http://s198.photobucket.com/albums/aa45/lionking_rocks/swiss%201911/

which I have barely fired other than test firing.It is shooting to the right and so far the front sight has been stubborn moving with a punch so I haven't fired it much until I get that fixed.

engravertom
September 8, 2009, 09:11 PM
Nice rifles! You have done well.

You may need to get a front sight pusher, or just whack it real good.

take care,

Tom

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