270 Winchester and IMR 7977

warboar

Beginner
Nov 1, 2020
22
0
This is my first post here on this site. I'm an avid Hunter, shooter, and reloader. I've been reloading since about 13 years old and am not 47. Don't claim to know it all but I feel pretty comfortable with loading ammo.

I've done several searches here looking for information on the 150gr Partition and IMR 7977 and came up empty. I decided to do a little experimenting on my own and go based on what Hodgdon had listed. I started at 58gr and worked up to 60gr. Wasn't sure the flat based Partition would produce more pressure than the Hornady bullet so I stopped there.

My rifle is a Winchester model 70 Featherweight with the 22" barrel.
All rounds loaded were loaded 20 thousandths off the lands at 2.776"(Comparter).
I used virgin Winchester brass and Federal 215 match primers.
All shots were from my bench with rear bag.
Velocity was measured on a MagnetoSpeed Chrono with fresh 9v battery.
Distance was 110yds (100M) it just worked out that way today.

The groups were less than stellar from 58gr to 59.5gr. The 60gr load produced sub 1 inch 5 shot group(i've never shot under an inch with a Partition in any of my other rifles).
I didn't see any of the typical pressure signs so I know I have a ways to go.
The velocity wasn't what i'm looking for at this point. I'm looking to be in the 2900fps realm but right now with the 60gr load i'm sitting at 2843fps average. Not sure .8 of a grain will get me much more velocity.

I brought a box of the Hornady Precision Hunter ammo with the 145gr ELDX along to see how they perform as well. 2790fps (2970 advertised on box)was what I recorded for 5 shots and accuracy was not that great either. Second caliber that i've bought and my rifles don't like.
 

gerry

Ammo Smith
Mar 1, 2007
6,117
9
Welcome to the forum.

I'm currently without a 270 Win right now but will get another one day for sure. IMR 7977 did quite well for me though with 60 gr and the 150 gr Ballistic Tip for a bit over 2900 fps with typically excellent accuracy. I also ran 60 gr with the 160 gr Partition for over 2800 fps and it grouped well too. I used Fed 215 primers as well. Rifle had a 23" barrel. With yours you may have a "slow" barrel or maybe the 22" barrel just gets a bit less speed, either way 2843 fps isn't too bad at all with a 150. I would try the extra 0.8gr to see what it does, it should be a bit faster and might even group a bit better you never know.
 

warboar

Beginner
Nov 1, 2020
22
0
gerry":37mj0g3a said:
Welcome to the forum.

I'm currently without a 270 Win right now but will get another one day for sure. IMR 7977 did quite well for me though with 60 gr and the 150 gr Ballistic Tip for a bit over 2900 fps with typically excellent accuracy. I also ran 60 gr with the 160 gr Partition for over 2800 fps and it grouped well too. I used Fed 215 primers as well. Rifle had a 23" barrel. With yours you may have a "slow" barrel or maybe the 22" barrel just gets a bit less speed, either way 2843 fps isn't too bad at all with a 150. I would try the extra 0.8gr to see what it does, it should be a bit faster and might even group a bit better you never know.
Thanks for the welcome and the insight.
I was thinking I may have a slow barrel as well. Years ago I had a 300Win that was slow. My brother’s rifle was a full 200fps faster than mine with the same ammo. I ended up moving that one on down the line.

My plan is to continue to work up to the max load and see where I end up. At this point there were zero signs of any pressure, bolt lift was effortless, and the brass didn’t appear to have any markings from ejector or flattened primers.
I think with the seating depth I’m at I could take it to the max or slightly above published max. I will load 60.5gr and then from there go up at .2gr increments until max. Hopefully I will continue to see good accuracy and a climb in velocity.
I have a few other powders to play with but they’re not temp stable like the Enduron is.
If I can find Reloader 26 I will give that a go as well. My brother has been working with it in his 7 Rem mag and is getting some great results with it.


Sent from my iPhone using Tapatalk
 

gerry

Ammo Smith
Mar 1, 2007
6,117
9
Please let us know how it work when you go up in charge weight. Sounds like you can still safely go up a bit.
 

ReloadKy

Beginner
May 13, 2020
234
34
Welcome, I love loading for my 270 . I started out playing with the 130 gr, got decent results our of a box of Hornady SST in 140 and I am now toying around with the 150. I have gotten excellent groups out the 150 Speer Hot-cor and 55 gr of IMR4831. Speeds were 2800 fps. I know I can get more with a different powder and anxious to hear more about your results with 7977.
 

Joec7651

Handloader
Apr 7, 2019
520
137
First, welcome to the forum. There are some really great people here. I’m not one to go with a powder because it’s the latest and greatest, but Staball 6.5 is really accurate in my 270 win with 130gr Partitions. A 56 grain charge has me averaging 3080fps with consistent half inch groups at 100 yards. Curiosity got the better of me and I tried it. So far it seems to be a consistent performer. I’m hunting with an E-Tip load with RL26 but my Partition load has the same POI and is my backup load if I forget the E-Tips. And I’ve done that, so it’s nice to have a fallback load you can count on. Again, welcome.
 

warboar

Beginner
Nov 1, 2020
22
0
Joec7651":ja3dg070 said:
First, welcome to the forum. There are some really great people here. I’m not one to go with a powder because it’s the latest and greatest, but Staball 6.5 is really accurate in my 270 win with 130gr Partitions. A 56 grain charge has me averaging 3080fps with consistent half inch groups at 100 yards. Curiosity got the better of me and I tried it. So far it seems to be a consistent performer. I’m hunting with an E-Tip load with RL26 but my Partition load has the same POI and is my backup load if I forget the E-Tips. And I’ve done that, so it’s nice to have a fallback load you can count on. Again, welcome.
Thank you for the welcome.
I too like to keep it simple and have a couple go to loads in my rifles. The 270 is new to me so I am starting from scratch.
I am basically looking for an all around load and this is why I’m looking at the 150 Partitions. I want an effective bullet for Elk and Mule Deer. The other bullets I’m looking at are the Berger and the Sierra Game Changer. I think the Berger would be a deer only bullet though because of their high fragmentation rate.

I’m looking at the IMR powder because it’s available and also is temp stable. Doesn’t hurt if it produces a little more velocity than older powders.
 

SJB358

Ballistician
Dec 24, 2006
31,254
419
I'd be just fine with running a 150 Partition up to 2900 with 7977 myself. It is a very slow burning powder, with the difference in cases used you are probably not treading on any sort of dangerous situation. I'd also chrono those same loads in once fired cases, you might be surprised at the speed you pick up. You might be closer to 2900 than you think.

Welcome aboard, always great to have another 270 shooter here!
 
Top