Home Forums Hunting & Shooting Hunting Rifles The Big 7's: 7 STW v.s. 7 Mashburn v.s. 7mm RUM

Been waiting for AZ to chime in.....he doesn't guess. He builds them and shoots them

Carry on the 7mm v.s .30 debate....this is a debate I've been having with myself as well...by all means, lets here it about Big 7's v.s. Big .30's

You could just build a 300 win mag, You'll get the velocity you want without any extra steps in reloading

Yeah I did that for a couple of decades....it got boring.


I think AZshooter brings up a really good point,and that is if you are looking for the very most you can get with the heaviest 7mm bullets,or 30 caliber for that matter, then these very long barrels of 28-30 inches make a lot of sense,if thats your style of hunting rifle.

But for a general purpose light sporter to be used under a range of circumstances,a shorter barrel is not a bad idea;personally I have no real interest in anything longer than 24 inches,and a rifle weighing no more than 8 pounds,and what you bump into is that the bigger cases frequently don't do much if at all better with these shorter barrels than some cartridges with a bit less capacity.Reason is you have hit the point of diminishing returns,and the larger case needs the longer barrels to realize full potential.If a guy has worked a lot with the 300 Win Mag and the 300 Weatherby he will run into exactly the same issue.

And the other thing you run into is that the bigger case may not do muc if any better than the slightly smaller case with lighter bullets.

For example, the Mashburn velocities we have known about for several decades was a 175 gr bullet at 3050 fps from the 22.5 inch barrel of Warren Page's old Betsy;any honest user of the 7 RM will tell you that its not easy to get that from the Remington cartridge with 22-24 inch barrels.From what I can gather 7mm cases with capacity of the Mashburn and Dakota sort of optimize what you can realize from a 24 inch barrel, if thats what you want.

So if a guy is not limited in what he wants for barrel length then the bigger cases can show an advantage,but I cant muster a lot of enthusiasm for burning north of 85-90 gr of powder in a 24 inch sporter weight rifle.

Don't know about the RUM but my 7mmRM was my only centerfire bolt big game rifle for 22 years (1982 through 2004 seasons) and during that time was the rifle I used daily during hunting seasons except for the one day each season I hunted with a Browning B92 .44 Mag Dad had given me.

So after an unknown quantity of 100-count primer boxes and at least two 1000-count boxes, I decided to work up a load for 160g North Fork bullets. I was rewarded with a .262" 3-shot group.

Never lost a big game animal or had to track one - most animals fell straight down or made it no more than a few feet. Two cow elk made it about 40 yards but the were the exception by quite a ways.

There was a bad experience with an antelope and a Barnes 160g XLC, but placement was fine (all three times!) and I blame the problem on the bullet. The XLCs made fine target loads after that.

Can't really complain.

+1

My 7mm RM was my first centerfire rifle and has never let me down. It may well be the last to go, too.

Not giving up my .300WM any time soon, though.

FWIW I just stepped out into the yard and shot my 300 win mag with a hand loaded 180gr Hornady at 3100 and my 7mm Weatherby with a factory loaded 160gr partition. The win mag did recoil abit more, but not night and day. I bet the difference with 165gr bullets in the 300 would have been very slight.

BC's really are not a factor for the majority of the hunting public. But if high BC's horn you up the Berger's in the 200-230gr range have very high BC's. IIRC a G1 of .753 for the 230gr Berger.

BTW I am no 7mm hater. I have done a good bit of work with the .280 Remington with great results, including a moose that went down right now. Its just the fact that if I am going to deal with the blast and recoil of a mag I would just as soon step up to a .300 magnum of some sort.

B W -

Now you are SINGING my song.

Sorry BobinNH.

I still have a couple of 7RMs but haven't hunted either since 07.

IF your going to go mag - GO MAG. GRIN

7 RM pressure issues: http://24hourcampfire.com/ubbthreads/ubbthreads.php/topics/6767453/Mule_Deer_7mm_Rem_Mag_Preassur . Not spikes as I read this, but more pressure variation than most cartridges.

I guess that would call for keeping the average pressure a bit lower than might be necessary w/o the variation.

Marlin -

I've had 7 mags for many yrs. I never heard of the pressure variations until joining the 'fire'.

I have always run max loads for the individual rifles. I've had normal case life and haven't had a SINGLE hard extraction or sign of a 'spike'.

So, I don't know really what to think about them (variations).

Maybe, .. those variations come into play 'more' at extremely high pressure loads.

When you've fired as many 100s, maybe 1000s of rounds w/o any problem ? ? as I have you are not overly concerned. At least I'm not.

I had to grab the first 7STW #1 I could get my hands on.

It does exactly what I bought it to do, with 160's at 3200 fps. And with all the recoil I want to deal with, especially after rotator cuff surgery, A tore up shoulder just never does completely get to 100%.

But I surely wish Ruger would have brought us the 375 Ruger case about twenty years sooner. And I wish Layne Simpson would have had it to build his cartridges upon.

375 Ruger brass is the ballistic twin of the 300/340 Weatherby and of the 8mm Rem mag/7STW. It is the case the firearms industry should have developed instead of recycling the old tired 300/375 H&H. If there was a commercially available source for 30-375 Ruger brass, I would sell the STW............no, make that..... rebarrel the STW to 7mm-375 Ruger.

A peek at RAMSHOT data shows max pressures for 7 RM at about 60.3 kpsi. Max of 7 WSM are about 64.0 kpsi and 7 SAUM at 64.1 kpsi. .270 Win max is at 64.7 kpsi.

I do not know why, but the 7 RM max pressure seems to be held somewhat lower than these others. Wider pressure variations (not spikes) could call for keeping the max average pressure lower for the 7 RM.

RAMSHOT data seems to allow these comparisons easily. It does not show every conceivable bullet for each cartridge, but you can get an eyeball scan of max pressures in the tables.

Well hell all this talk about holding 7 RM pressures to 60k or so is academically interesting but the average handloader couldn't tell the difference between 60k and 63k in his loads without 6 computers and a pack of bloodhounds...

I heard about this stuff in the 7 RM and the 243 before I joined the CF but had no idea people got so hung up about it,even though I have no doubt its true....so what

If you read between the lines, we know that both are the most popular cartridges in their class;if we read what guys like Mule Deer and Mic McPherson have said about it, its related to the short necks and ,and the highs and lows can be an issue with worn throats....why the same condition does not show up with the 264 Winchester and the 300 Win Mag I have no idea,but maybe it does and no one talks about it...Mmmm..

In any event I've personally worn out several 7 Rem Mag barrels without a hint of difficulty;never a blown primer,and honestly don't ever recall seeing an ejector slot mark on brass...and this included running 140's at close to 3300 in one rifle and the 160 gr to 3125 for enough rounds to cook the barrel, which took about 10 years of hunting and shooting in total and lots of rounds.That was one tube....there have been several others.

I don't load to those levels anymore and when I see 3200 with a 140,and 3050 with a 160;toss in 3150 with a 150, I just call it good enough and run with it.

Am I loading over 60,000 psi... In all likelihood, yes,but who knows and so what.I am not going to get blown into DNA.Factory ammo has to be held to those levels to allow for the variation,and the fact that a cartridge as popular as the 7RM is going to vary all over the map in barrel/throat/leade dimensions and configurations and the makers never know what rifles their loads or ammo will be fired in....all of which has nothing to do with MY loads in MY rifles.

The thing I always liked about the cartridge over its lesser siblings is its generous case capacity...and if we assume as we must that manuals like Nosler are holding to the 60,000 psi limit,a close look will tell us it still produces top velocities even at that level.

In short,and again....so what.

As to targets and dropped shots at distance I have not seen it in the short 3 round groups I usually fire at distance, but then again its a hunting cartridge that heats barrels and I would not pick it for long strings of shots or as a target round...there are better cartridges for that kind of thing and its' been awhile since I killed an animal with a group anyway

If it all bugs a guy to the point of distraction,he can punch the damn thing to a MASHBURN and all the problems go away..longer neck, more capacity and life is good.....or he can get a smaller case and load it to 65,000 psi to do almost the same thing but that always struck me as an ass-backwards solution to a non-existent problem.

Call me crazy...