Anybody have a recipe for Varget using 180's in the 7.5x55..?

All my manuals are empty...

I'm testing a bunch of powders and would really like to try some Varget loads.

You are working up, right? Just about any 7.62X51 load will work in the 7.5X55, including Varget. The cartridges are ballistic twins. When using the same bullets and powder charges, one (308) uses higher pressure with a lesser case volume, the other(Swiss) has lower pressure and larger case volume, and the velocities will be real close with each other.best-o-luck

What rifle is it chambered in??
I wouldn't start using .308 loads in 7.5x55 case without known what was wrapped around it.

Gents

Rifle is a K-31.

Yes I'm working up and I'm not looking to hot rod. I'd read the 7.5 is loaded to a lower pressure than than the 7.62x51 but didn't know where was safe to start.

I believe the originals barrels were .307 bore, which is close enough to use .308 bullets.
Original spec was 46k PCI
CIP spec is 55k PSI.

Here is what QL predicts with a 180gr BT.

Cartridge : 7.5 x 55 GP11 SWISS
Bullet : .308, 180, Nosler AccuBond 54825
Useable Case Capaci: 55.776 grain H2O = 3.621 cm³
Cartridge O.A.L. L6: 3.059 inch = 77.70 mm
Barrel Length : 24.0 inch = 609.6 mm
Powder : Hodgdon VARGET

Predicted data by increasing and decreasing the given charge,
incremented in steps of 1.111% of nominal charge.
CAUTION: Figures exceed maximum and minimum recommended loads !

Step Fill. Charge Vel. Energy Pmax Pmuz Prop.Burnt B_Time
% % Grains fps ft.lbs psi psi % ms

-11.1 80 40.00 2298 2110 35756 7082 96.2 1.491
-10.0 81 40.50 2323 2157 36870 7172 96.6 1.473
-08.9 82 41.00 2348 2204 38016 7260 96.9 1.453
-07.8 83 41.50 2373 2252 39196 7346 97.3 1.433
-06.7 84 42.00 2399 2300 40410 7430 97.6 1.412
-05.6 85 42.50 2424 2348 41659 7512 97.9 1.392
-04.4 86 43.00 2449 2397 42945 7591 98.2 1.372
-03.3 87 43.50 2474 2446 44268 7668 98.4 1.353
-02.2 88 44.00 2499 2495 45630 7742 98.7 1.335
-01.1 89 44.50 2523 2545 47033 7814 98.9 1.316 ! Near Maximum !
+00.0 90 45.00 2548 2595 48476 7884 99.1 1.298 ! Near Maximum !
+01.1 91 45.50 2573 2646 49962 7951 99.3 1.281 ! Near Maximum !
+02.2 92 46.00 2597 2696 51492 8015 99.4 1.264 ! Near Maximum !
+03.3 93 46.50 2622 2747 53068 8076 99.6 1.247 ! Near Maximum !
+04.4 95 47.00 2646 2799 54690 8135 99.7 1.230 !DANGEROUS LOAD-DO NOT USE!
+05.6 96 47.50 2670 2850 56362 8190 99.8 1.214 !DANGEROUS LOAD-DO NOT USE!

If it was my rifle, I would probably start around 40gr and work up. That might be a little on the conservative side, but I'm always willing to trade a little powder and lead for more data.

Thanks a MILLION...!

That's what I was looking for.

Antelope Sniper, I did say something about working up. I'm curious, would you post the QL predictions for 7.62X51 and Varget.
The 308 is usually loaded a step up from the 7.62, but no matter. Until a decade or two ago, for a grand or so, a custom K-31 rifle was available in a single shot platform in 300 Mag. The single shot was due to catridge lenght.
?PCI? Is that supposed to be CUP? 55K PSI by CIP is not going to be the same as 55K PSI by SAAMI. As per an old Model 1911 spec sheet from W-FBern, the federal Swiss arms manufacturer, it specifies that the max working pressure for GP-11 ammo is measured at 3200bar or 3200 kg/cm(pretty close to 46KCUP) and the correct bullet diameter in inches as .3087". W-F also said that barrel dia spec is .3063-.3087". They also mention a minimum bullet dia as .3071",FWIW.
When I requested data through the Swiss Embassy's Attache, I didn't ask for 31 data as I did not own a K-31, as cheap 31's were over $500 back then. More FWIW, both the 11's and 31's were availble in 308 from Switzerland. Many M-11's and K-11's were converted outside of Switzerland. Not so with the K-31's even though the 31's are much stronger actions, because rebarrelling a 31 is a lot more involved than an 11 type. Barrel lenghts: K-11 is about 23" K-31 is 26".
Plenty of misinformation still abounds for the Swiss rifles. For giggles, check out and compare Sierra's data for the 7.5X55 and the 308. For similar bullet and powder weights, the vels are near identical. best-o-luck

quote:

Originally posted by Andrew Davison:
Anybody have a recipe for Varget using 180's in the 7.5x55..?

All my manuals are empty...

I'm testing a bunch of powders and would really like to try some Varget loads.

Andrew,

I tried 6 powders including Varget some yrs ago for 180 SGKs in my 7.5x55. I used the 308 starting load an worked up from there. Due to a computer crash where I lost my reloading notes, I can't give you the exact max I worked-up. But do remember it worked.

What I found was that IMR-4350 outperformed the other 5 powders in my rifle for both the 165 and 180 bullets - So, I've just stayed with that one powder ever since.

If you are looking for powder recommendations - I'd recommend trying the IMR-4350.

Mike, you have some very good questions.
CIP and SAAMI are two different orginazations that rate cartridge limits. In general, SAAMI is US centric, while CIP is more Eurocentric. It's very common for the two to disagree on how hot a cartrige can be loaded. On the .303 Brit, SAAMI rates it at 49k PSI, but CIP rates it at 53k PSI. On the .270 Winchester, CIP rates it at 62k PSI, but SAAMI rates it at 65K PSI. I don't always understand the reasons behind the different rating, so when it's my face behind the bolt of an old military rifle, I prefer to start with the more conservative measure and work up.

Between the 7.5 x 55, and the 7.62 Nato, there is a significant differnce in rated case capacity. The Swiss if rated at 55 3/4gr H2o, but the Nato round is rates at 41gr H2o.

Here what QL predicts for the 7.62x51 Nato, with a 180gr Nosler AB, Varget, and a 24" barrel.

Cartridge : 7.62 mm NATO (7.62 x 51)
Bullet : .308, 180, Nosler AccuBond 54825
Useable Case Capaci: 41.079 grain H2O = 2.667 cm³
Cartridge O.A.L. L6: 2.800 inch = 71.12 mm
Barrel Length : 24.0 inch = 609.6 mm
Powder : Hodgdon VARGET

Predicted data by increasing and decreasing the given charge,
incremented in steps of 1.25% of nominal charge.
CAUTION: Figures exceed maximum and minimum recommended loads !

Step Fill. Charge Vel. Energy Pmax Pmuz Prop.Burnt B_Time
% % Grains fps ft.lbs psi psi % ms

-12.5 96 35.00 2267 2054 40801 5792 94.4 1.402
-11.2 97 35.50 2298 2110 42483 5878 94.9 1.377
-10.0 98 36.00 2328 2167 44247 5961 95.4 1.353
-08.7 100 36.50 2359 2224 46085 6042 95.9 1.329
-07.5 101 37.00 2389 2282 48002 6121 96.3 1.306
-06.2 102 37.50 2420 2341 50002 6196 96.8 1.283
-05.0 104 38.00 2451 2400 52099 6269 97.2 1.261 ! Near Maximum !
-03.7 105 38.50 2481 2460 54281 6338 97.6 1.239 ! Near Maximum !
-02.5 106 39.00 2511 2521 56552 6405 97.9 1.218 ! Near Maximum !
-01.2 108 39.50 2542 2582 58920 6468 98.2 1.197 ! Near Maximum !
+00.0 109 40.00 2572 2644 61396 6528 98.5 1.176 !DANGEROUS LOAD-DO NOT USE!
+01.2 111 40.50 2603 2707 63987 6584 98.8 1.157 !DANGEROUS LOAD-DO NOT USE!
+02.5 112 41.00 2633 2771 66700 6637 99.0 1.137 !DANGEROUS LOAD-DO NOT USE!
+03.7 113 41.50 2663 2835 69542 6686 99.3 1.118 !DANGEROUS LOAD-DO NOT USE!
+05.0 115 42.00 2693 2899 72521 6732 99.4 1.099 !DANGEROUS LOAD-DO NOT USE!
+06.2 116 42.50 2723 2964 75647 6774 99.6 1.081 !DANGEROUS LOAD-DO NOT USE!

Snipe, Thanks for the last post. FWIW, CIP measures pressure in front of the case mouth and SAAMI measures pressure at mid case. I'd guess that your QL is using mil brass(thicker) instead of something like Win cases. Hodgdon's site does show 308 and varget with a start load of 41grns@ 2470fps, which is 3 steps into your dangerous load-do not use chart. Hodgdon's 308 max is 45grns@ 2661fps.
Andrew, Ray is giving you good advice, IMR4350 is an excellent choice, along with H4350. IMR 4064 is another good choice. Many powders will work well. I've not used varget myself. Some may disagree(HOT C) but a chrono is a good thing. 7.62Nato and 7.5X55 mil rounds with 175-174grn bullets should, in a 26"tube, push about 2550fps. best-o-luck

Mike, Thanks for the info on CIP vs SAAMI. Quickload is a great tool, but it's not perfect, and I still have alot to learn about it.

QL actaually list both the 7.62 x 51, and the .308 Winchester. Of course they technically have different throats, I think you are correct that with the Nato cartridge QL assumes a heavy military brass. I thinks it's for the 300 Win Mag that QL list 4 different brasses just to give the user an idea how brass can affect the results. Maybe this winter I will get a little more serious with it and create my own case files by weighing out the brands I mostly commonly use in my favorite cartridges.

Thanks for all the info guys.

My rifle ended up liking the 4350 load....

This is plenty good enough to hunt with, don't think I need to develop any further.

Andrew, thanks for the update.

What was your final load?

Pvri Cases
WLR Primers
180 gr. Remington AccuTip/Hornady SST's
45.8 gr of IMR 4350 (Sierra Manual most accurate..)
Crimped with Lee Factory Crimp
COL 2.900"