Compressed Load Question

NC-rifle

NC-rifle

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I was surprised to see what appears to be a compressed load situation. I would like your feedback.
This is Varget powder (short extruded), in Prvi Partizan PPU 308 Win cases.
I did the load development up to 44.0 grains of powder, and everything shot well. No signs of over pressure on any cases or primers (CCi #34).

When preparing to load a few boxes (60 rounds), I decided to make this powder level "gauge" to see where the powder level is relative to the bullet base. These are Hornady .308 SST 165gr projectiles. Well to my surprise, setting the "gauge" into the case with 43.7 grains of Varget, looked like this picture. Even after lightly pressing the "gauge" into the powder with my fingers, it didn't reach the position where my loads placed the bullets (2.750 C.O.L.), using the cannelure.
The Hornady load book shows up to 44.0 grains of Varget with this bullet, at this C.O.L.

Thanks for your input.

Bullet-Powder_Depth-post.jpg

Hornady_165_SST_load_dataPost.jpeg
 
I was surprised the bullet was contacting the powder.
Is this more normal than I thought?
Is this amount of compression resonable? 0.040-0.060"
 
With regular 308 loadings, Varget is hard to go over pressure with. You'll crunch the hell out of it and pressure will still be well under 62k.

Ultimate reloader just did an awesome segment just a few days ago about this very topic. They used some kind of build that was specifically built for 308 over pressure. They used Varget and 215gr pills. They went up to 47gr of Varget and 100k PSI!!!! They were literally pushing the upper velocity limits of 300 win mag! They took 308 out to a friggin mile. Pretty amazing honestly. My biggest question is how in the hell did they get the bullet seated?!?
 
I have 4 loads for Varget in 308 and the lowest one is 43.4 grains and goes up to 46 grains. Bullets are 175,168,150 grains. If I recall correctly all crunch but one. I love Varget in a 308. Nice choice.
 
I dont recommend compressed loads with Varget or any powder for that matter. There is no need to hot up 308 to that level. I'm not familiar with the Ultimate Reloader segment mentioned above but I hotted up some 308 Varget loads and was popping primers and bulging brass. Not cool. Old Sierra book shows 41.7 max Varget for a 175gr pill. You can go hotter but what does it do to the accuracy?
 
Every Varget .308 round I ever loaded crunched. They all touch the powder.

Check fired cases for pressure signs but OP using all Hornady data and components is a feel good.

Cant speak to internal capacity of that specific PPU brass tho - there are some noticeable differences across the spectrum of headstamps.
Weigh a few and compare to Federal / R-P etc. Matters at highest load densities.
 
I load 43.6gr of RE15 which is very very similar to Varget using 165gr Tipped Game Kings and 168gr SMK and get the “crunch” also. I’m not using PPU brass but primarily FGMM, Hornady, Nosler, and occasionally LC M118 brass

At first I thought I was getting cratered primers, but after some more studying and the same primer signs on very reduced loads, I determined it was primer flow from a too-large primer pin channel in the bolt face of my Rem 700.
 
Jmoser said:
Cant speak to internal capacity of that specific PPU brass tho - there are some noticeable differences across the spectrum of headstamps.
Weigh a few and compare to Federal / R-P etc. Matters at highest load densities.
Click to expand...
For what it is worth, these were my measurements of case capacity. Other's results may vary...
Mainly I plan to use both PPU 7.62x51 cases that I fired in my AR-10 style rifle, from PPU 7.62x51 147gr factory ammo;
and some PPU 308 Win cases I bought from NEReloading.
Weights were with a spent primer, and I calculated cc from the weight of the water.

Case Volume 308 - Jim.JPG
 
And I just weighed 4 cases (not cleaned) of LC 22 that I fired in my rifle from factory Winchester 7.62x51, 175gr Match.
181.9, 182.6, 182.6, 183.4
 
NC-rifle said:
And I just weighed 4 cases (not cleaned) of LC 22 that I fired in my rifle from factory Winchester 7.62x51, 175gr Match.
181.9, 182.6, 182.6, 183.4
Click to expand...
That’s not huge variance imo. I just got 1200 or so once-fired FC. A sample of 100 of them averaged 181.3 with SD ~.9. They all shoot very consistently.

Edit: should add that all my loads are crunchy and while primers are a little flatter close to 44gr (178 ELD-X) they still reload well.
 
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I reloaded some 5.56 well within the book numbers for a 75gr bullet and I was crunching powder for them to meet the cartridge OAL. No flattened primers though?
 
jimmyjames8 said:
I dont recommend compressed loads with Varget or any powder for that matter. There is no need to hot up 308 to that level. I'm not familiar with the Ultimate Reloader segment mentioned above but I hotted up some 308 Varget loads and was popping primers and bulging brass. Not cool. Old Sierra book shows 41.7 max Varget for a 175gr pill. You can go hotter but what does it do to the accuracy?
Click to expand...

In my experience, the burn rate of Varget gets much more consistent when it's compressed.
Groups shink measurably.
 
I am loading 44.5 grs of Varget in lapua brass with a 168gr nosler match on top. No signs of pressure in my primers
 
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