Reloading 7PRC

Did some test firing yesterday.
ADG new brass
Fed215
69g H1000
175 ELDX

Man... These bullets like to jump. Factory hornady 180eldm jumps .120 before hitting the lands on my rifle.

5 rounds at the following .120, .095, and .070 jump. Yes I know you're not supposed to care about jump but its a good starting point for setting up your dies and adjusting them when throats start to erode

.07 was like 2" group,
.095 was 1.25" group
.120 was sub 1" but my 3rd round was shot shortly after my first 2 'cold bore" shots. 3 shot drifted out and the last ones came back

Gonna load up 15 more rounds
.125, .120, .115 to see which ones are happiest

Speed is somewhere 2930 fps based on some velocity ladder readings i took with 180 bergers, but I wanted to hone in the seating depth before I took velocity readings
What length barrel?
 
I got 2800 with 69.9 of ramshot grand with a 20" barrel, berger 180s and new adg brass. I did no other work up, just grabbed the hodgdon max charge and loaded up 10 .020 off the lands.

I was getting 2825 out of factory Hornady 175 (early hot loads - r26) and Federal 175 eldx (also r26?).

These are the 10 loaded.

1000004384.jpg

My next try is 10 more seated 0.070. I'm working under the assumption that berger vld-h like very little or a lot of jump.
 
Here's some more handload data for copper solids.

I ran the Patriot Valley Arms Cayuga 151 gr in the 7PRC (22" Proof 1:8 barrel). Because I haven't shot any solids this light in the 7PRC, I started with N565 at 70gr. Wasted some projectiles on the low end, but hey, it's all shootin' fun. Got to it late because I had to get a hay field tedded, so I had the sun in my eyes on my range.

I started with a COAL of 3.1900" I suspect more jump would improve things. I used White River Energetics LR primers. FYI - they are tight in even 5x fired Peterson pockets! I'll try magnum primers of different flavors later.
The numbers:
70gr. - 2894fps
70.5 - 2935
71 - 2943
71.5 - 2949
72 - 2970
72.5 - 3009
72.8 - 3021
The group:
PVA151 ladder.jpg

The group measured 1.20" at 100yds, and shots 5 & 6 are close. #7 went flying. Those charge weights - 71.5-72gr. - may call for more experimentation, although I'd like to get more velocity. I can probably push it to 73.5 gr. and see how they fall in the group so I'm not leaving any N565 on the table. I'll switch to a slightly faster powder such as H4831sc.
 
I ran the PVA Cayuga 151gr in the 7PRC (22" proof barrel) - this time with H4831sc. First I did a ladder test with Fed 215 LRM primers, Peterson brass 5x fired and annealed. COAL is 3.160"
FYI - I'm at 156' elevation, and the temp today was 74F, 66% humidity.
Results:
66 gr- 2961 fps
66.5 - 2986
67 - 3043
67.5 - 3043
68 - 3087
68.5 - 3086
69 - 3095 No obvious pressure signs
Then I threw another 68 and 68.5 gr with a COAL of 3.180" for the heck of it to see jump/velocity sensitivity
68gr - 3059 fps
68.5 - 3065 fps
The target: Shots 8 & 9 landed over shot 6)
151C LRM H4831sc ladder.jpg
 
So then I changed the primer only in the above to White River Energetics Large Rifle primer, with a COAL of 3.180".
The results:
67gr - 2974 fps
67.5 - 2997
68 - 3049
68.5 - 3087
69 - 3054 (?)
69.5 - 3110 Slight ejector swipe
The target:
151C LR H4831sc.jpg

Since shots 4,5 & 6 were on top of each other, I took the 68.5 grain load and stretched it out to 400 yards with a guesstimated 5 MOA come-up.
Results:
#1 - 3081 fps #2 - 3018 fps #3 - 3045 fps
Odd to get that must ES from H4831. Shots 1 & 3 were on top of each other, and shot 2 was about 2" low and 1.5" left. These all are small sample sizes, but I'm encouraged to explore the 68.5 to 69 grain area with H4831sc I won't get any more velocity from it, but it will have to do as an accuracy load for elk hunting next month, as I'm running out of time.
151C LR H4831sc 68.5.jpg

151C LR H4831sc 68.5 bullseye.jpg



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