I want a 7 Mashburn Super. Don't ask me why, and I don't need to rationlize it. I have three good 98 actions - an FN, a Husky, and a Mark 10, all 3.4 inch mags. Can one of these be opened up at the rear enough to take the Mashburn, which is nearly (not quite I think) 3.6 inches. Yeah, I know, I can do it on a 700 Rem or a Model 70, I just don't want to do it that way. Yeah, I'm nuts, as I already have a 7 Rem, but the 7 Mashburn Super is what the 7 Rem should have been. My 7 Rem is on the FN action. No I don't want a 7 Dakota or a 7 Weatherby!

7mm Super Magnum Mashburn



This case is about .20 shorter than the 300 or 375 H&H and about .12 longer than the standard mag cases like the 7 rem mag.

I've never done this case on any rifle but would guess that there's room at the rear of the FN and similar M-98 actions to hold it.

No rationalizations needed. We are mostly all nutso too.

Here's some reloading data from Nosler

175 Nosler Partition Hodgdon H-870 82 3,026
175 Nosler Partition IMR IMR-7828 72 3,055
175 Nosler Partition Hodgdon H-4831 71 3,008
175 Nosler Partition IMR IMR-4831 67 3,000
175 Nosler Partition IMR IMR-4350 64 2,968
160 Nosler Partition Hodgdon H-870 84 3,205
160 Nosler Partition IMR IMR-7828 74 3,238
160 Nosler Partition Hodgdon H-4831 73 3,118
160 Nosler Partition IMR IMR-4831 68 3,116
160 Nosler Partition IMR IMR-4350 65 3,130
150 Nosler Partition IMR IMR-7828 75 3,300
150 Nosler Partition Hodgdon H-4831 74 3,239
150 Nosler Partition IMR IMR-4831 70 3,252
Remarks: velocity from a 69-grain charge of IMR-4831
150 Nosler Partition IMR IMR-4350 67 3,236
140 Nosler Partition IMR IMR-7828 76 3,375
140 Nosler Partition Hodgdon H-4831 75 3,305
140 Nosler Partition IMR IMR-4831 71 3,373
140 Nosler Partition IMR IMR-4350 68 3,314

Thanks Folks. I guess I just want enough encouragement to go ahead and do it. I just wish Rem had done it for me. Good shooting!

Many years ago,when i first started out i built a 300 super Masburn on a 1917 Enfield actiion. A little work was involved but it was a heck of a rabbit killer shooting 100gr half jacketed speer bullets. lol. Another off the wall i liked,was the 270 Durham Mag.These both are in Ackleys books. van

[QUOTE]Originally posted by vapodog:
Here's some reloading data from Nosler The 7mm Mashburn Super is in about the same category as the 7x61 S&H.(HIGH PRESSURES) I have the reamer, but will no longer use it. The FN 300 and 400 series were a bit soft...sure ebnough, the locking recess in the action set back until you could no longer lift the bolt (without a hammer)...This is GOOD..stretch before break! I never had this problem with the good military Mausers..they are carburized in the right places, but what the heck, why holdthis bomb within a few inches of your face? I would advise anyone to forget about both the Mashburn and 7x61..borderline dangerous!

Duane.
So you have one of those reamers also.
From what I understand JGS only made about 9 or 10 of them.
I also made one rifle up for a customer years ago. Have not used the reamer since.

Paul.
In my mind the 7mm STW is a better cartidge, now since you can buy ammo and cases for it.

Jim Wisner
Custom Metsmith

Jim and Duane: I really appreciate your taking time to respond to my inquiry. What would be wrong with this round just working within the reasonable pressure range (58-62 k psi)? I know the 7 STW is available, but the Freak factor isn't there. Its more a nostalgia trip for me than anything else. It seems this round would be pretty similar to a 7x300 Win, with the bullet seated out to full length. In fact, that would be a good option. My 7 Rem is throated for seating a 160 spitzer to the base of the neck, oal about 3.36. I haven't chronied it ever, but I expect it is running pretty good. I've had this rifle 30 years or so, and I will give it to my son in the next year or so. It still has a BL Balvar 5 on it! If I wsanted to use common sense, I'd take one of the 06's I have (Springfield, Husqvarna and Mark X) and just have it rechambered to 30/338 - lots more practical. I don't have to get all the performance a 7STW will give - just what the 7 Rem was supposed to give in the early days. I blew the lugs off a FN bolt in the early days of my reloading - I've learned my lesson the hard way - BTW the FN action didn't set back, tho I was concerned that it had. I had the headspace checked since and it is still right on. (This was a real blue pill, not a regular load!!!!!)

So my question still stands - I expect you guys know the answer - can the Husky or Mark X be opened up to take this round, loaded to about 3.55 oal? I don't want to make a bomb out of it - and this will probably be the last rifle I ever put together (no pun intended hahaha). I had rather put a couple inches more on the barrel and run a little cooler. Just something for an old guy with coronary bypass to do in the winter time! hawhaw. Plus I'll be the only guy in Denver that has one.

BTW, what is all this stuff about the 7 REm running sporadic high pressures?

thanks again all. Keep shootin!

I'm certainly in no position to encourage you to proceed with the Mashburn configuration

Duane: Thanks for your honest answer. I reconsider it. PAG

quote:

Originally posted by Duane Wiebe:
[QUOTE]Originally posted by vapodog:
Here's some reloading data from Nosler The 7mm Mashburn Super is in about the same category as the 7x61 S&H.(HIGH PRESSURES) I have the reamer, but will no longer use it. The FN 300 and 400 series were a bit soft...sure ebnough, the locking recess in the action set back until you could no longer lift the bolt (without a hammer)...This is GOOD..stretch before break! I never had this problem with the good military Mausers..they are carburized in the right places, but what the heck, why holdthis bomb within a few inches of your face? I would advise anyone to forget about both the Mashburn and 7x61..borderline dangerous!

Duane, are you referring to chambering the Mashburn on a mauser action only, or any action? I have had several on Remington 700 actions without any problems, and I know Page and Hagel never had any trouble either. The Mashburn is quite a bit more cartridge than the 7x61.

Sambubba: Thanks for your comment. I have a 721 action that I know is long enough for this round. I had wanted to build it on a Husqvarna Mauser, which is the nicest action I have, but the lengthening might not be practical. I know the 721 is stouter than the 98. Will have to get new bottom metal and magazine as this one has -of all things - a detachable box magazine. I hate to pull that nice 06 barrel off it. What kind of performance did you get out of yours. Have not given up on my idea yet, as it should outrun a Weatherby slightly. It should be a good performer with powders like 7828, H1000, Retumbo, Re25, and the slow vit powders with the heavier bullets. An alternative would be a 300 Win case necked down to 7mm and throated for an OAL of 3.5. That lets you seat the long 160s to the base of the neck and almost the same with the 175 Swift aframe, Speer GS, etc. However, this is a nostalgia round, but could be a good one used with reason.

I get 3300+ fps with the 160's and 3050--3100 with the 175's. The 140's are 3400++. I use IMR 7828 exclusively in mine. I have three different barrels for this cartridge, and two of them don't get quite the velocity of barrel #3. I use 300 win mag cases run through a forming die--Winchester brass only. It is a great cartridge for both accuracy and velocity. When you throat a 7mm Rem mag where 160g bullets are flush with the base of the neck, the Mashburn is not a whole lot faster, but I believe it gives me better accuracy. My barrels started off as the Rem version.

Samb: thanks for this info. Practically speaking, I think I'll look for a Rem 700 in 7 rem and rechamber. Anybody out there got a 26 inch stainless Remington barrel they don't want. I had a 7 Rem with one of those - most accurate rifle I ever owned. The Mashburn should run a bit faster than any Remington configuration and a bit faster than the Weatherby with same barrel length. I have a bunch of stuff I've collected and I think I'll sell down to one or two rifles I like to fool with. I do have the 721 action I can build on - just need a barrel and bottom metal. I still say that's the round Remington should have done - They had all the action length they needed. Would not have to run high pressures - and would have beaten the 7 STW by 30 years.

Have found my project rifle - an older Sako in 7 Rem. It (the action) looks full length - I have to measure. Just a rechamber job, and presto, I have my Mashburn Magnum, at only about 400 dollars more than what I can set up in the 7STW in a Mark V action counting a 150 dollar die set and 100 Norma cases. At least its cheaper than sex, and probably a lot safer! Thanks for the help. This will be a rifle with a high "cool" factor! Now I've gotta sell off the other stuff to have time to play with it.

quote:

At least its cheaper than sex, and probably a lot safer!

You might want to look at that Mashburn again!!!!!

Yep, I got the Sako. A long action Finnbear in 7 Rem Mag for 550. 3.6+ Magazine. Now to figure out what to do with it. Either a 7 STW or a Mashburn Super, the rifle I wanted since I was 19 and read all those Warren Page articles on the 7 Mashburn. Think I'll shoot it first and see how the barrel does! My old 7 mag does good with 160 grain Sierra's and Speers with 7828. Here's to luck.