7mm PRC & N570

[TxLite]

Looking to see if anyone has any experience with this combo. Looking to add some speed over my H1000 load with 180 hybrids. I’ve done some looking around but haven’t seen a ton of people that are using this combo. Maybe there’s a reason?

Berger data shows it being nearly 100fps faster than H1000 but don’t want to burn up components if it’s not worth exploring.

 

[wapitibob]

not my load, and 195's

7 PRC
26-inch, 1:8 twist barrel
195 gr Berger
66.9 gr N570
.030” OL
2.676 CBTO
3.434 COAL
2954 fps ave

 

[TxLite]

not my load

7 PRC
26-inch, 1:8 twist barrel
195 gr Berger
66.9 gr N570
.030” OL
2.676 CBTO
3.434 COAL
2954 fps ave

I always question Berger’s data. With those 195’s they show 71.4gr max with a max velocity of 2913. It was the same story for my 300prc. Definitely have to be careful with their info.

Thanks for sharing

 

[Nbowlin]

560 has given me the best speed accompanied with accuracy in a lot of rifles. On the 20-24" stuff. FWIW

 

[TxLite]

560 has given me the best speed accompanied with accuracy in a lot of rifles. On the 20-24" stuff. FWIW

Thanks. I eyeballed 560 and 565 and they seem to be right in a good spot for the 7. I’m worried 570 will be too slow burning. I’ve got plenty of h1000 and no real “need” to change it up but I’ve got 11lb of 570 leftover from a rifle I sold so I’d like to find a use for it. The Berger data has me wondering.

 

[MisterOrange]

^^^^ plus one for N560 if you want speed in 7PRC. I took @Nbowlin 's advice on it and he was spot on. Accuracy was great as well. Although I did find it had some velocity changes with temperature.

I never tried 570 in the 7PRC I had, but I'd wager you will run out of room in the case before you pressure out.

 

[eoperator]

Looking to see if anyone has any experience with this combo. Looking to add some speed over my H1000 load with 180 hybrids. I’ve done some looking around but haven’t seen a ton of people that are using this combo. Maybe there’s a reason?

Berger data shows it being nearly 100fps faster than H1000 but don’t want to burn up components if it’s not worth exploring.

Did you give 7prc 180g n570 a try?

 

[TxLite]

Did you give 7prc 180g n570 a try?

I haven’t yet. It’s on my to-do list but shooting time has been limited lately. I’ll post the results when I do

 

[wind gypsy]

I’m just here to agree that Berger’s load data sucks.

 

[B23]

I'm not sure if you can get enough N570 in that case to get more speed out of it compared to some of the other powders.

I have a 7mm Blaser mag which is nearly a twin to the 7PRC and I'm using 68.5gr RL26 w/180 Berger hunting vld's and from my 26in Hart barrel they're right at 3100 but my chamber has also been +P'd.

 

[TxLite]

I'm not sure if you can get enough N570 in that case to get more speed out of it compared to some of the other powders.

I have a 7mm Blaser mag which is nearly a twin to the 7PRC and I'm using 68.5gr RL26 w/180 Berger hunting vld's and from my 26in Hart barrel they're right at 3100 but my chamber has also been +P'd.

Playing around with Gordon’s reloading tool, it shows me at 2715fps with 104% fill volume at a max charge of 73gr N570 with 92.8% burnt propellant in my 18” barrel, which seems to fall in line with some of my other powder choices. I think I still might give it a shot and see if GRT proves accurate. So far it has been dead on with my current h1000 load.

For comparison it also shows the following at a max charge (estimated 65,000psi)

H1000 (have)
2719 fps
104% Fill volume
69.5 Max charge
96.8% Burnt

Retumbo (have)
2736 fps
104.9% fill volume
73gr max charge
100% burnt

R26 (don’t have)
2737 fps
93% fill volume
67gr max charge
100% burnt

 

[B23]

FWIW, N570 has big fat long powder kernels so using a longgggg ass drop tube will definitely help you get more in the case.

 

[Odd1out]

FWIW, N570 has big fat long powder kernels so using a longgggg ass drop tube will definitely help you get more in the case.

Also using vibratory toothbrush once its filled and touch it helps lay those 570 logs down tight

Sent from my SM-G986W using Tapatalk

 

[TxLite]

Also using vibratory toothbrush once its filled and touch it helps lay those 570 logs down tight

Tooth brush was a great recommendation.

I loaded some up tonight from 69gr-73gr in half grain increments. This was the final load, pre tooth brush-



I was able to seat the bullet post tooth brush with the slightest (almost nothing) crunch.


Planning to shoot this weekend. Will update with results.

 

[TxLite]

First load of the day. Ain’t mad at it. (I know, I know, 3 shot groups)

 

[TxLite]

Following up as promised. Overall very pleased with both the garmin, N570, Peterson brass, and this c6 barrel. One shot missed on the Garmin (user error??). No pressure signs at 73gr with a velocity average of 2820, a full 200fps faster than my H1000 load. That being said my H1000 load is low, and I was able to hit 2670 today with it by going up a full grain higher than my existing load. Pic of case head below is from the 73gr N570 load.

The group with ADG was 5 shots. The rest are all 3. As a point of reference, the dots are .75”

 

[WKR]

73gr of 570 sounds pretty damn spicy
I'd be curious what pressure you're at with that load.

Sorry if I missed it but what action and barrel length?

 

[TxLite]

73gr of 570 sounds pretty damn spicy
I'd be curious what pressure you're at with that load.

Sorry if I missed it but what action and barrel length?

Tikka action, 18” carbon 6 barrel.

According to Gordon’s reloading tool I’m right at max load. Berger data says I can do another grain and a half

 

[eoperator]

Tikka action, 18” carbon 6 barrel

New barrel? How many rounds on it?

 

[TxLite]

New barrel? How many rounds on it?

Nope, around 180 after today.

Edit- my math was off. 205 on the barrel after today.