7mm RM and N165 - issues...

[DJL2]

I recently came into some ADG brass after waiting patiently on my back order. I had done some load development with Hornady brass, but started again with the ADG stuff. In addition to RE23 and H4831sc, I added VV N165 to the mix (i.e. all temp stable powders). Tested two loads today, here's what I saw:

Bullet:	Primer:	COL:	Powder:
Matrix 168​	CCI 250	3.325	N165
59.5	60	60.5	61	61.5	62	62.5	63	63.5	63.9
2225	2448	2457	2531	2476	2570	2507	2545	2629	2633

I started here: https://www.vihtavuori.com/reloading-data/rifle-reloading/?cartridge=74
As you can see, loaded right up to VV's book max...but, something is definitely up. This was a new 1lb jug. There was soot all over the cases, clearly not getting a good seal with the chamber wall. Any idea WTF happened here?

PS: I had a velocity node around 2890 or so with the H4831sc in Hornady brass. I know the ADG is supposed to be "faster" (potentially) with the same powder weights...didn't see that. I did transition from MSv3 to LabRadar for the readings, so might be some "noise" there. My results were essentially identical.

 

[clcustom1911]

If you don't have signs of high pressure, then keep climbing. Clearly you have signs of low pressure/poor seal with carbon on the necks, so keep on keeping on. I run 68.5 of R26 under 168's in ADG brass and get 2980 from my 24" Tikka.

Do one round each at 64.5, 64.8, 65.1, 65.4, 65.7, 66, 66.3, 66.6 and see where high pressure signs start (ejector swipes, pancake primers, primer flow, stiff bolt lift, tough extraction, etc), then go no further. Now you know your max for YOUR rifle.

 

[Steel head]

N165 is not an energetic powder like the 500 series.
Keep stuffing more in.
I don’t have my notes but I was about at your top charge with 168’s in a smaller 7 saum case with no pressure.

 

[DJL2]

The carbon was all the way back to the belts...just wild. The oddity here is that factory ammo runs like it says on the box for this rifle, but everything I've loaded so far has been slow by about 50-100 fps or so when loaded to published max. I suppose I must be using conservative load data...hmm. 2900 w/ 168s is about what I'm seeing for both RE23 and H4831sc (with the RE23 running marginally faster).

I'm aggrieved that I'm spending some much time just trying to get into the ball park for which components might actually produce a decent load. It's tempting to say "f- it" at this point. I'm gonna swap the bottom metal and stock here soon, which changes my options for COL as well...currently my mag max is leaving the bullets a good .1" off the lands.

I bought this as a project rifle, so I suppose I'm getting what I asked for...

Side note: I think it's pretty cool that VV publishes the energy density for their powders.

PS: RE23 and 162 gn Amax in Hornady brass was @3010 and climbing linearly at book max (67 gn), also with a node @2900 fps (64.6-64.9 grains).

 

[DJL2]

I’m out on N165. Loaded up to 67 grains, still only 2725 FPS or so. No idea why, it just doesn’t build pressure. Done messing with it, RE23 is giving me pretty much everything I want anyway and H4831sc isn’t far behind.