7PRC load data starting point

[Klransom]

I just got a Seekins Havak Element in 7PRC and need some starting points for loads to try. I have 168 vld hunters, 175 elite hunters, and 162 eldms for bullets options. I have Staball HD and N565 for powder. Has anyone had good luck with any of those bullet powder combos?

 

[TxLite]

This is directly from Berger for the 175 EH and 168 vld.

 

[Klransom]

Cool thanks, I also have a little N570 and H4831sc that are on those charts I can try.

 

[LFC911]

I would start with the N570, I haven't tried it (i use RL26) but everything else I read looks like that would be the next best choice.

 

[Bobbysdoinwork]

Im working up the 168s right now in a ruger american predator peterson brass winchester magnum primers i will post my results after this weekend still on my load ladder

 

[Klransom]

I ended up finding the magic load it was N570 with the 180gr ELDM it ended up killing a deer, elk and moose this fall.

 

[Gadjet]

I ended up finding the magic load it was N570 with the 180gr ELDM it ended up killing a deer, elk and moose this fall.

Define "magic". What kind of groups and velocities are you getting?

 

[TxLite]

I ended up finding the magic load it was N570 with the 180gr ELDM it ended up killing a deer, elk and moose this fall.

Great job. We need some terminal performance pics and load details

 

[Klransom]

73.0gr of N570
About 12 thousandths off the lands.
2984 FPS out of seekins element so a 22 inch barrel.
Out of 3 different 5 shot groups had a max ES of 17 and SD of 7.
Groups were around .5 moa plus or minus a little depending on the day.

 

[Klransom]

 

[TxLite]

73.0gr of N570
About 12 thousandths off the lands.

That’s where I ended up as well in my 18”, but 65 thousandths off with 180 Berger hybrids.

 

[goathunter]

73.0gr of N570
About 12 thousandths off the lands.
2984 FPS out of seekins element so a 22 inch barrel.
Out of 3 different 5 shot groups had a max ES of 17 and SD of 7.
Groups were around .5 moa plus or minus a little depending on the day.

Curious - Is the seekins a hinged floor plate or magazine? How long is the OAL, can you seat the bullet in the case optimally?

 

[Klransom]

It's a custom carbon fiber magazine made by seekins and there is lots of room in the magazine way more than needed to reach the lands. I am seating them at 3.392.

 

[jeetS]

That’s where I ended up as well in my 18”, but 65 thousandths off with 180 Berger hybrids.

@Klransom @TxLite

Looks like over 3grn over max according to VV...any pressure signs? Throat wear?
Assuming youre crunching it in there?

 

[TxLite]

@Klransom @TxLite

Looks like over 3grn over max according to VV...any pressure signs? Throat wear?
Assuming youre crunching it in there?

Berger lists 74.3gr max. Work up for your rifle.

No signs of excessive pressure (besides high velocity). Have not checked for throat wear (don’t care to, will make necessary adjustments if groups open up). Powder is crunchy unless I settle it by tapping the case on the bench or use an electric toothbrush to vibrate it.

 

[Klransom]

I tap the brass a few times some people use an electric toothbrush to vibrate it and settle the powder down and it fits fine. No pressure signs, i got pressure signs with H4831SC and Staball HD but not the N570.

 

[jeetS]

Thanks!

 

[Article 4]

My 2 cents - I tried 565 and it was a bit snappy and less responsive to group tests. N568 is probably a great sweet spot for this load and that bullet - I run it in my 7-300 PRC wildcat and will the case is a bit larger, the burn rate is nearly perfect with less worry about throat erosion that can sometimes come from 570.

 

[jeetS]

Isnt the n568 the same burn rate as n565 just bulkier?

 

[Article 4]

Isnt the n568 the same burn rate as n565 just bulkier?

According to Vhit there are some small differences. Small energy difference and small burn rate difference. They are both made for big cases with big bullets. mine liked the 568 better.

Not too different from H1000 to Retumbo.

570 is closer to 50 BMG