Home Forums Hunting & Shooting Long Range Hunting 7MM Mashburn Custom

LOL, Yup, that old heavy duplex Leupold 3X is now matte cerakoted midnight blue and bolted to the top of a 98 Mauser 458 Win Mag via a set of Talley lever locks.

Sounds like a good one. You sent it back for heavy duplex, replaced the #4...

Cerakote sounds good. That scope had seen heavy use, hauled around for years in a pickup, mounted on a Ranch Rifle, busted a bunch of 'yotes. The finish had a few slick places.

Those M8 3X Leupold scope are about bullet proof, hard to kill.

Should do well on that big boomer.

DF

Sometimers moment, meant heavy #4, no, no changes except for the paint job, it's right at home now, what in hell am I gonna do with three 458 WM rifles?

Thought I remembered you thinking that reticle was too heavy.

It is sorta heavy, but those things do have their place. LR target shooting not part of it...

DF

Used a little RL33 with 175 Partitions in my old Mashburn. 570 would probably work darned good too with 175's and heavier. I got an easy 3100 with Retumbo and 33 out of the old rifle.

N-570 isn't that easy to work with, but the performance should make the extra effort well worth it.

I recently got some, haven't had time to put it thru the paces. I'm trying it in the 26 Nosler instead of the standard 869. I'm also trying it in my 7RM with heavy bullets. It should work even better in your Mashburn.

I would love to see a QL print out on the Mashburn with heavy bullets. I'll bet n-570 will be at or near the top of the list.

DF

The great thing about the MSM to me is it super easy to work with compared to a RUM or STW.. being as it is set up for long seating it has PLENTY of space for the slow, dense powders. Even with 83 grains of 33 it was still very lightly compressed. It's not a miracle round at all but it is anything but finicky. Even good old H4831 does well, but just isn't as fast as those ultra slow powders.

My only complaint is having to do inside neck reaming to get rid of the donut after forming, but once I figured that out, it's been super easy to load for and the speeds are there.

Yes, the reticle is too heavy for what I was going to mount it too, BSA's old pre-64 M-70 375 magnum.

With the 458, shooting couch and footstool [pigs] sized animals at spitting distance, it's perfect.

Great news on the 33 with the 175's beretz, a man can go a good long way out at 3100 fps with a great b.c. hunting bullet.

Gunner, I figure I'd add some of the pieces I use for the Mashburn. There may be a couple lurkers that wanna run a Mashburn Super. Looking at the amount of dies I have for it I should have my head examined but I dig the sucker.

These are the form and trim dies I use. You could get by with trying to jam virgin brass into a plain old FL die but the first time you crumple a couple of expensive RWS or Norma cases the F&T dies look a lot better.

https://www.midwayusa.com/product/5...-7mm-mashburn-from-300-winchester-magnum

I will get you the part number of the Redding FL bushing die as soon as I get home or I might be able to get my boy to get me a picture. That sucker is awesome for getting the perfect .003" neck tension.

Here is the pin gauge set I use

https://www.amazon.com/gp/product/B00UCQO1UM/ref=oh_aui_detailpage_o06_s00?ie=UTF8&psc=1

I just got the whole kit. Works good for my other stuff as well. Seems like neck tension means something. Ha. Who'd a thunk it! Plus it makes identifying donuts after making a new shoulder a cinch.

Thanks beretz, I appreciate it, still mulling 175's at 3100, that's gonna leave a mark.

I'll click on the link with a pad and paper at the ready, just hope I get work done early enough tomorrow to order some parts.

I also have the K&M neck turner. I actually just use the inside cutter since I'm not a neck turner. Works like a champ though. I chuck it up and hammer through the cases.

After those all you'll need is a seater die. I use Redding but RCBS works fine as well.

Appreciate this too.

10-4 thanks, looks like a nice tin of Imperial Wax may be in order too.

For danged sure. It works flat awesome.

3050 is no big trick. Seems like Page crushed about everything with 175's back in the day!

The 175 BBCs were the two quickest elk kills I've had so far. Hit me again 10 years and we will see if it holds up!

Has anyone out here tried H870 in the 7 mm Mash super. I have several pounds to use up and I'm just finishing the stock on my build so need to be thinking about load development. I also have lots of R 19 & 22 as well as H4831sc. Will be working with Hor
175 & 160 eldx as well as Nosler 175 partitions. Any assistance would be appreciated. Thank you. Feel free to pm me with your thoughts.

Never used H870, but it should work fine.

Generally you can use 7mm Weatherby data and work up.

As to powders, 22, 7828 and 25 are pretty good. I use a bunch of H1000 and Retumbo mostly since I'm working with 160-175's.

LOL, oh too have a box of 1000 of those bullets, damn!

I've got about 200 of them. Should be able to do something with em...