7-300 Long Range Improved

[762 ULTRAMAGA]

I recently had Dave Manson design a reamer for me based off the 300 WSM and soon to be released ADG brass.
It's called the 7-300 Long Range Improved (LRI)
It's a necked down 300 wsm with the shoulder blown out to 45 degrees.
I decided on 45 because 40 didn't seem like enough improvement on the 35 degree shoulder of the parent case, also I wanted to maximize case capacity and 100% stop case growth.
Plus no one's doing 45 degree shoulders so I just wanted to try it.

I love the WSMs for their effortless accuracy and efficiency, the most accurate rifle I ever owned was a 7 wsm.
My objective was to build a lightweight 18" 7mm that would maximize velocity with 180/195 Bergers for my primary elk rifle.
I hunt elk in everything from thick timber to cross 800 yard clear-cuts here in Idaho, a suppressor is a must in this invironmemt where shot opportunities can come and go in a matter of seconds.
I cover lots of miles in thick mountainous terrain, and believe I've built the perfect rifle for the task

I had McGowen barrel make me a factory tikka contoured 18" 8 twist prefit with the muzzle flared up to .730 for 5/8×24 threads
The barrel came in at 2 lbs which is even lighter than I'd expected!
All set up with a vx5 HD in talley rings with the factory stock, and 9" Banish 30 suppressor it weighs 8lbs 5 oz.
I'm about a month out on a custom CF lightweight LR stock from MPI, it should come in sub 20 oz so the final weight will be around 7lbs 13 oz.

I'm still waiting for my custom dies from Hornady but in the meantime I used a 270 wsm die and a .284 expander to size a few winchester cases down.
I fire formed with 15 grains of unique topped with TP and got a near fully formed case, fully formed capacity is 82 grains with WW brass.
Pretty darn good considering the parent case measured 79 grains in 30 cal
Shooting 195 EOLs I worked up to pressure while zeroing at 100 yards, and ended up at 2815 with 70 grains of N570!
Accuracy is outstanding even with crappy brass, I'm getting sub 1/2" groups edge to edge.
More load data to come when I get the dies, and ADG brass.

1. Fireformed next to parent case


2. 7-300 LRI 195 next to 30 Nos 220 lrht


3. Loaded with 195's


4. Scoped and suppressed


5. Muzzle flare


6. Setup


7. 100 yards

 

[WeiserBucks]

How does it feed? I've heard that sharp shoulders can cause feeding issues but I don't have any experience with them.

 

[762 ULTRAMAGA]

It feeds flawlessly, one thing I like about detachable mags is they're the smoothest/most reliable option with pretty much any case.

 

[WeiserBucks]

Are you going to try the 180 Hybrids? They're by far my favorite 7mm bullet on game. I've seen the 1st gen 195's do some goofy things on elk and haven't revisited them in years, are the current ones updated at all?

 

[762 ULTRAMAGA]

Yeah I'll give them a try if they ever hit the shelves again..
They'll be jumped a country mile but I'm guessing they would still shoot.
I haven't made any kills with the 195's but I've spoke with a few guys that really like them, the tips absolutely need drilled out though

 

[JoeB]

Looks like a winner for sure. Should be a good elk thumper

 

[Mike D Texas]

Very nice. I just built a 264 Win Mag Improved. Mines a long barrel but the total weigh with suppressor is just under 10#. Right at 9# without suppressor.

Manson built my reamer as well. He does good work. It’s a shooter. Fire formed cases went from 80.2 grains to 87.3 grains.

This is my sight in target. Shots 1-3 were dialing in (shot 1 is out of the picture frame). Shots 4-6 went .099 MOA.

Fireforming 1.5 grains under max. No brass prep at all. 156 Berger EOL.

Sent from my iPhone using Tapatalk Pro

 

[762 ULTRAMAGA]

Very nice. I just built a 264 Win Mag Improved. Mines a long barrel but the total weigh with suppressor is just under 10#. Right at 9# without suppressor.

Manson built my reamer as well. He does good work. It’s a shooter. Fire formed cases went from 80.2 grains to 87.3 grains.

This is my sight in target. Shots 1-3 were dialing in (shot 1 is out of the picture frame). Shots 4-6 went .099 MOA.

Fireforming 1.5 grains under max. No brass prep at all. 156 Berger EOL.

Sent from my iPhone using Tapatalk Pro

Wow that's a zinger
How long is your barrel?

 

[z987k]

It feeds flawlessly, one thing I like about detachable mags is they're the smoothest/most reliable option with pretty much any case.

What mags did you go with?

 

[762 ULTRAMAGA]

What mags did you go with?

Mountain tactical LA magnum

 

[Mike D Texas]

Wow that's a zinger
How long is your barrel?

28” Proof Sendero.


Sent from my iPad using Tapatalk Pro

 

[762 ULTRAMAGA]

Update:
I got my custom Hornady dies a few days ago and started load development with ADG 300 wsm brass.

Unformed brass measured 78 grains H2o capacity, fireformed is 81.
I settled on a load with 70 grains N570 pushing a 195 2700 fps, I maxed out around 2775 in 15 degree weather with .7 accuracy but ES was pretty poor.

The node at 2700 produced an ES of 6 with groups in the .5s, that'll get me to 900 yards at 3500' with an impact velocity of 1800 fps.
Plenty for my intended elk hunting ranges.

I loaded one case over and over for testing with various powders working up to max loads.
I put some ejector marks on the brass and after 27 loadings the primer pockets are still tight!
WOW ADG brass is way tougher than Lapua without a doubt.
Also I only had to trim the brass twice, keep in mind these were hot loads with FL sizing, I did anneal every 5 shots

Here's a pic of the loaded case after 27 firings next for unformed brass, and a 195 loaded in a mountain tactical mag

 

[762 ULTRAMAGA]

I scored some 180 Berger vld targets and came up with an awesome load with 66 grains of RL26 and .070 jump.
.7" group at 200 yards and it chronoed 2800 fps.
Interesting enough I shot 2 groups at .045 jump and they were both exactly 1.75".
It seems the vld really likes a bit more jump, at least in my barrel.
I'll take it to 1k after work for drop validation

 

[hereinaz]

That's a sweet set up. You are definitely good to go at 800 yards.

Love me some 7mm short mag improved. Short mags with sharp shoulders have run perfectly in every mag fed rifle I have seen. And, they absolutely are so easy to load for and tune. I couldn't use group size to pick my load, they all shot sub .75. I am not as adventurous as you, so I have been using Rich Sherman's wildcat short mag, the 7 SS and the 180 vld hunters. You should love the 180s on elk, My 7ss took an elk at 1000+ yards with one shot. Running a MV of 3050. A buddy built a twin 7ss to mine, and he took one at 1000+ with essentially the exact same load. He put two shots behind the shoulder before the elk tipped over, but he was dead on his feet after the first one.

And, ADG brass is awesome stuff. Its what I got from Rich Sherman for my 7ss.

 

[762 ULTRAMAGA]

That's a sweet set up. You are definitely good to go at 800 yards.

Love me some 7mm short mag improved. Short mags with sharp shoulders have run perfectly in every mag fed rifle I have seen. And, they absolutely are so easy to load for and tune. I couldn't use group size to pick my load, they all shot sub .75. I am not as adventurous as you, so I have been using Rich Sherman's wildcat short mag, the 7 SS and the 180 vld hunters. You should love the 180s on elk, My 7ss took an elk at 1000+ yards with one shot. Running a MV of 3050. A buddy built a twin 7ss to mine, and he took one at 1000+ with essentially the exact same load. He put two shots behind the shoulder before the elk tipped over, but he was dead on his feet after the first one.

And, ADG brass is awesome stuff. Its what I got from Rich Sherman for my 7ss.

Thanks yeah I'm a huge shortmag fan for sure.
Good to hear with the 180s, mine are the VLD target so I'm hoping they perform similar to what you've seen with your vld hunters.

 

[Cahunter805]

Awesome wildcat! Congrats. That’s some impressive work and brass life is outstanding! I’ve had good results from the 195s but have read about some poor results. I do pin drill all of mine just to be sure though.

 

[hereinaz]

Thanks yeah I'm a huge shortmag fan for sure.
Good to hear with the 180s, mine are the VLD target so I'm hoping they perform similar to what you've seen with your vld hunters.

I questioned other guys using the target hybrids instead of the hunters, but I haven't heard any complaints or about guys switching back. Lots seemed to prefer the hybrid damage, less explosive with a little more penetration because the match jackets are just a bit thicker. The hybrid shape is easier to load as well. As I understand, the 175 elite hunter are hybrid shape, not the VLD, so guys wanting to use hunting version drop to them.

 

[Bater]

Oh damn....Looks about perfect for western hunting!

 

[Clownbuster]

Curious on any updates to this? My 28" 7-300WSM shoots the Berger 180gr Hybrid Target right at 2975fps with 64.5grs of H1000.

 

[Clownbuster]

Where do I get me hands on this reamer and die set??