175 Nosler Partition and 7mm rem mag

[tyson22250]

Just wondering if anyone has played with the 175gr Nosler Partitions in 7mm rem mag? I have a remington 700 sps that I am trying to get theses things to shoot a little tighter. I have worked through rl 22 and was pretty disappointed and I am Now onto Retumbo. Anyone know how much jump these heavy Partitions like? I have worked through from 65gr-68gr of retumbo with hornady brass, Cci 250 primers all cases trimmed, weight sorted and even bullets weighed. Started with a COL of 3.295" and at 68gr I found that there was some potentional there and then started playing with seating depth further in and found it to get much worse so started seating them closer to the lands at .020" from the lands it had 3 touch but in vertical stringing even after letting barrel cool good between shots. Question is should I keeping seating closer to lands or play with powder charge? All I have read or tried to find it seems like the partitions like more jump. Just want to hear some others input. Thanks

 

[Darkhorse]

I worked up some loads back in the early 80's. We were more limited in powder then and the Partitions were semi-spitzer.
My load was 58 grains IMR 4350, WW cases, WLRM primers. I was trying for .020 jump but my methods back then were cruder than now, so I'm not sure what the actual jump was. Don't know the MV as I had no Chrono.
Accuracy was right at 3/4" for 3 shots.
I ended up using Speer Grand slams because they had more of a spitzer point and I figured they would range better.
I was happy with 3/4" then but I don't think I'd settle for that now.

 

[Bruce Mc]

My Win model 70 screams a 175 Partition at 2986 fps with 72 grs of Retumbo, winchester case and Federal mag primer. 3.37 OAL. I load to fit the magazine because the rifle has a long throat. I've shot several 1/2" groups with this load. I'll measure the length of a Partition with the comparator and let you know exactly how far it is.

 

[Partisan]

Try 0.010 to 0.020" off the lands.

 

[Bruce Mc]

I pulled out some loaded rounds and ran the comparator on my rifle. I guess I'm getting too old to work from memory. The OAL of my rounds are 3.302 and the comparator length is 2.770. The comparator length of the throat with the 175 Partition is 2.795. That gives a distance from the lands as 0.025. At least I remembered the right load and velocity.

 

[tyson22250]

Thanks Bruce!

 

[Guy Miner]

They're good bullets! I was close to Bruce's velocity with good old H870, which is no longer avail. Switched to RL-22, and got good results though the velocity wasn't as high. Not bad though...

Accuracy was hovering around 1 MOA for me, with my good ol' Rem 700 ADL and a 3-9x Leupold. More than good enough to drop a big Wyoming bull with one shot. The long & lethal 175 Partition will penetrate!


The 175 Sierra SPBT Gamekings were actually more accurate, but I went with the Nosler for penetration. In retrospect, I'm sure the Sierra would have done just fine.

Sorry, I can't answer your other questions. Sold that rifle years ago. Can't quite remember why, it was a good hunting rifle.

Regards, Guy

 

[DrMike]

I worked up loads in my Winchester Model 70 Featherweight with 61.5 grains of RL22. I've also worked up loads using 74.0 grains of H870 and 71.0 grains of Magnum. All these loads shot sub-MOA. I load these with 0.010 to 0.020 inches of jump to the lands. I actually used more 175 TBBC during the earlier years when I was using this particular rifle quite a bit. More recently, I've focused on the 175 PT, and it gives me acceptable accuracy.

 

[baltz526]

http://www.gibrass.com/gunpowder.html This is a link to 870 take down powder for sale. I have not bought any, But the site has been around awhile. If you want H870 which was a military surplus powder. This list the same powder recycled from Ammo

WC870 Here is some of the exact original type powder as was sold by Hodgdon, called
H870, until discontinued. A ball powder originally used in the 20mm Vulcan
round, until replaced by WC872. This powder is also very similar to Accurate
Arms AA8700. Because of the lot to lot variations in burn rate, be sure to
begin with listed starting load data. Works great in the .50BMG and other
large capacity magnums.
This is pulldown ball powder.
$48/8# jug; $176/4-8# jugs ($44/jug); $240/6-8# jugs ($40/jug)

 

[Guy Miner]

Good to know.

H870 was sooty, but accurate and moved that 175 fast.... I no longer have a 7mm Rem mag, but if I did I'd grab 8 lbs of that 870 and happily load nothing but 175's.

Guy

 

[baltz526]

It would be interesting to find out if its Available. Through the site. I tried 1lb of H870 and the 175gr Partition. Still have part of the lb. 77gr gave 2830-2850fps

 

[SJB358]

Very cool stuff here. I tried some RL22 and 175 PTs. Got into the low 2900's pretty easily but I never finished the load work. I believe I was in the .020-.030 range as well. Guy is right though, there can't be many animals those suckers won't shoot clear thru.

 

[russ808]

I used IMR4831/60 grains, with cci mag primes.
Russ