7x57 Ackley Improved Pet Loads?

[cal30_sniper]

Looks like I'm going to pick one up this week. Marquart Precision built on a 98 action with a 22" Barrel. I've got a couple of small ring 95s in regular 7x57, but I've never loaded for the AI before. I was wondering if anybody here any pet loads they really like, and corresponding velocities.

Right now I'm loading 139grn Hornady SP over 46.5 grns of H4350. That, as well as 145 grn Winchester and 139 Grn Prvi ammunition is what I plan to fireform with. I'm wondering if I should keep loading 140grn pills in the AI, or step up to 150 or 160 grn bullets. Lower velocity, but harder hitting and better BC. Thoughts?

This reloading scare kind of caught me with my pants down. I have IMR-4064, IMR-3031, and H4895 lying around that I use to load other calibers, as well as the H4350 I use in 7x57. I can still get RL19, if anyone has used that successfully?

Thanks for the help, looking forward to everyone's input.

 

[Patocazador]

I had used a 7x57 AI for over 30 years and have taken over 100 game animals with it including 13 in Africa. It is a great caliber - good accuracy, good range, relatively light recoil, and about equal to a .280.
My pet load was 52 grains of IMR 4350 with CCI BR primers and a 140 grain Nosler Partition bullet.
I took 2 elk at ~ 450 yards with it along with kudu, zebra, gemsbok, moose, and a couple of black bears.

SAD NOTE: I lost it in a cypress swamp a year ago when I got caught in a lightning storm and dropped it to run and dive for cover in the dark. I couldn't find it afterwards even though I got a search team of 3 people and went back 3 times.

You will LOVE it.

 

[cal30_sniper]

Bob,

Thanks so much for the tip! Sorry to hear about your rifle, have you found something to replace it with yet?

I'm sorry it took me forever to get back to this, but I've been snowed under trying to get my thesis finished. I finally turned it in on Friday, so I've had some time to play with loads this weekend.

I ended up testing today at 100 yards with H4350, 139grn Hornady BTSPs, and PPU once-fired neck-sized cases. I started with 48.0 grns, then 49.0, and 50.0 grns before I started shooting the target below. The next five groups were 5 shots each, 50.5grns (UL), 51.0 grns (UR), 51.5 grns (BR), 52.0 grns (BL), and 52.5 grns (Center). Only one of those groups slipped over 1", and that was my fault. The guy next to me at the range was shooting a 300 Win Mag, and his report went off just about the time my trigger broke. I threw that shot low and to the left in the bottom right group.

I didn't get any pressure signs at 52.5 grns, but I think I'll leave it at 52.0 for my final loads. I don't want any pressure issues shooting down here on 105-110 degree days, and I really don't feel like pushing a 104 year old rifle too hard anyways. If I wanted a 7mm Rem Mag, I'd go buy one.

Not bad for a vintage rifle and a vintage scope, thanks so much for the tip on the loads!

 

[the Black Spot]

You might consider varget for this round

 

[Bwana John]

My "pet mule deer load" for my standard 7mm Mauser (in a rem 700) is 51 gr 4350 with a 140 Ballistic Tip.

 

[cal30_sniper]

My "pet mule deer load" for my standard 7mm Mauser (in a rem 700) is 51 gr 4350 with a 140 Ballistic Tip.

That's a lot of powder for a regular 7x57 case. I load 46.5 grs of H4350 in my 95 Chilean (small ring so I keep it down some), but even that fills up the case pretty good. How compressed is that 51 gr load? It might be something to try in my Brazilian 1908 if it's pretty accurate.

You might consider varget for this round

Don't have any Varget. I've heard it works well over a large range of calibers, but usually isn't ideal for any of them. What specs do you load it to in the AI? How were your results? Right now I'm working with H4350/IMR4350, IMR4064, IMR3031 and H4895/IMR4895. I may end up picking up some H4831/IMR4831 for my .270 as well. Right now primers are my limiting factor. I dipped down below 200 for the first time yesterday. I haven't been able to find any since early January. I probably will just be producing loaded rounds with what I have left. Hopefully someday soon I can find some more and commence load development again.