Home Forums Hunting & Shooting Ask The Gunwriters 7mm Remington Magnum?

Laughing! True!

Mule Deer
In your travels what has been the availability you have seen for the 7mm Rem Mag around the globe?
GreggH

I’m 45 and own a sako fiberclass and a semi custom 700. 160 accu bonds in the sako used to be my main squeeze. Worked good for lots of deer, coyotes and elk.

GreggH,

7mm has been very available everywhere I've traveled, except perhaps not quite so much in Europe. Oh, it's available in gun shops, but not like it is in Africa or Canada.

John

Any chance we would ever see an article on whether long throating the 7mm rem mag or the .30-06 actually works? Some of the older articles like dog zappers in the .30-06 and Wootters made it seem almost magical. Lot of respect for those two guys but I always wondered if it wasn’t like the extra velocity in an AI coming from higher pressures

Kellywk,

That's been my experience.

While longer throats do allow more velocity, it's not as much as many people believe, mostly because they've never performed their experiments while actually testing pressures at the same time. This is true whether the longer throat is used to seat bullets further out, or simply to serve as "freebore," as in the Weatherby rounds.

The basic rule of thumb is the 4-to-1 Rule I developed by crunching the numbers from a bunch of pressure-tested loading data: Any increase in powder capacity results in about 1/4 as much increase in potential velocity--at the SAME pressure. This was confirmed in a different way by the late Don Miller, the guy who developed the rifling twist formula used almost universally these days.

Let's say somebody lengthens the throat on a .30-06 by 1/4 inch. This results in .0186 of a cubic inch of extra powder space--.25 inch times the cross-sectional area of a .30 caliber bullet, .0745 inch. This amounts to about 5 grains of extra powder space, which sounds like a lot until you consider the .30-06 case holds about 60 grains of powder with a 180-grain bullet seated. The longer throat thus results in about an 8% increase in powder room--and 1/4 of 8% is 2%.

If the .30-06 is capable of 2800 fps with a 180 (and it is, even at SAAMI pressures, with some powders), then the extra 2% will up the potential velocity to about 2850--again, at the SAME pressure.

But if we increase the pressure from the SAAMI maximum average pressure (MAP) of 60,000 PSI to 70,000 PSI (about where many "pressure signs" used by handloaders typically start appearing) the velocity can rise to around 3000 fps--or even a little more, depending on the powder.

Is this safe? Absolutely--in those conditions, in that rifle. But pressures are never constant, even with today's far less temperature-sensitive powders, the reason SAAMI (a collection of ammo and firearms manufacturers) has yet to approve a MAP of over 65,000 PSI: There are too many variables to expect 70,000 PSI to work safely in every rifle, under all conditions.

Which is exactly why I conducted the experiments with the .223 Remington, loading it up until "pressure signs" appeared, then backing down to the last load that didn't results in any such signs. Obviously that load was safe in the pair of .223s I tested it in, but the velocities were so close to those quote by fans if the .223 Ackley Improved there was no practical difference. Which indicates the velocities achieved by .223 AI fans are almost entirely due to more pressure, not the little bit of extra powder room.

And a little bit extra powder room, whether in freebore or seating bullets out farther, is what throat lengthening is all about.

Staying under SAAMI the 65K in the 7mm Rem Mag, it took a 26 inch barrel and R26 before I could ever reach 3100fps with a 160gr. ( I used the Sierra 160 HPBT) I "chased" that 3100 several times throughout the past 40 'with 24" barrels and older powders. I realized If I wanted that ( or more!) I had to use a 26" barrel and went to , first, the 7mm STW. Even then, 3100 "with great accuracy" was 50/50. Then I was gifted a 25" 7mm RUM. Now we're cooking! ha. However, I actually settled on the 140 TTSX and its best accuracy ( 3400). I've had a few rifles that shot faster, but for the most part, their best accuracy was at a bit slower speeds. For "sure fire speed results though", get a bigger round, ha.

I just finished up the 7mm RM article Wednesday, and sent it off. In the 24.4" barrel of a Mauser M18, 67.0 grains of RL-26 got a little under 3000 fps with more than one 160-grain bullet. The maximum charge of RL-26 listed in the latest Speer manual for 160s is 66.3 grains, which is also listed at a little under 3000.

But as I also point out in the article (which is about new powders and bullets) most new bullets these days have higher BCs than the typical softpoint flat-bases used for years in the cartridge. Today's bullets don't need to be started as fast to obtain "magnum" downrange ballistics.

“Montana seems to me to be what a small boy would think Texas is like from hearing Texans.”
John Steinbeck


Except in the case of Montana - it's true!

Any mention of the “new 7mm mag” in the form of the .270 Winchester, 150 grain bullets and RL26?

I'm 50 1/2 and never used a 7 mm Rem mag but am a fan of the slower and more nostalgic 7mm. I haven't been checking the fire as much since I am working from home and doing a little more domestic work. Can't read the fire during lunch like I used to. Any way missed this poll until today.

Spent a few minutes last night looking at the latest Nosler data for LR Accubonds in 30-06. I'm interested in high BC 180-200ish gr loads for the 30-06. A Creedmoor for old guys. For some reason, went to look at the 7 mm Rem Mag data too, and was impressed with the possibilities. Impressed enough that I started to search for my first 7 mm Rem mag...

JB, what publication will the article appear and about when...want to make sure I have good reference material.

It will be in Handloader in a couple months.

The .30-06 also works a lot better than many 21st-century handloaders can apparently imagine with new bullets and powders!

I got my first 7mmRM in 2005, a used 1977 Ruger #1, I am 69 years old. I killed (3) mule deer in 2011

I had been hunting with a pre 64 M70 Win 270, but the 7mmRM could hit the 10" circle every time at 500 yards and the 270 was only sure in my hands to 400 yards.

I built a 7mmRM with a VZ24 Mauser. I got (1) mule deer and (1) antelope in 2012

I built a 7mmRM with a 1963 Rem700 action. I got (1) mule deer in 2014

I bought a 1994 factory Browning 1885 7mmRM I got (1) mule deer and (1) antelope in 2015

I built another Rem700 7mmRM. I got (3) mule deer and (1) white tail deer in 2017... that little WT doe was a 630 yards [tiny target]

I have also built a Mosin Nagant 7mmRM and never shot anything but targets with it.
I have also built (2) 1908 Braz Mausers 7mmRM and never shot anything but targets with them.

I also have Winchester, Savage, and Remington 7mmRM factory rifles I have not shot, but might rebarrel.

I have(2) 7mmRM reamers and (1) 7mm throater.
I have (11) 7mmRM dies. You know you are a nerd when you have all dies on a spreadsheet.


My brother is 62 and has shot deer, antelope, and elk with his factory stock Rem 700 7mmRM.

My current 23" barrel 30-06 does 2825 with Re16 and 180 Accubonds. A 0.507 BC makes this combo a flat shooter and wind bucket - with a big game bullet. At a shade over 7lbs it is also delivers tolerable recoil. I did a bunch if gacking a few years back on 7RM and various cartridges in that class to evaluate ballistics. At 500 yard or less there ain't much difference in a 270, 280, 30-06, 7RM, etc.... using some type of heavier Accubond. If you can shoot over 500 yards accurately, you can find differences and certain cartridge/bullet combos started to pull away.

For me, I dont shoot past 500 yards so I'm cool with the 'standard' cartridges. I aim, pun intended, for lighter, shorter rifles that deliver a big game capable bullet on target at a level of recoil acceptable to me. Which falls in the 270/280/30-06 category.

I'm 72 years old. I own one 7 Remington Mag. I bought it off a Gun Broker auction for $205.00. The only reason I bought it was for a donor action for a proposed .308 Norma Build. But right before I began that project I had the opportunity to buy a Mark V .300 WBY. for a good price. Since this was one of my grail guns I snapped it up and decided to keep the 7 RM as is.

I've since discovered this is one of my most accurate rifles. I've tried several loads in it. I've tried 140 grain both Nosler and Combined Technology Ballistic Tips, 150 grain Nosler Ballistic Tips, and 160 grain Sierra Game King Hollow Points. All three shot well in my rifle. I've used IMR and Hodgdon 4831 and RL-22 with all three of those bullets. I've found the 7RM very easy to load for.

However, my go to hunting rifle is my 54 year old Winchester Model 70 .270 Winchester I bought brand new in 1966.

[quote=GF1]Any mention of the “new 7mm mag” in the form of the .270 Winchester, 150 grain bullets and RL26?[/quote

Now you've got my curiosity up. Since ,my old .270 has virtually in the last 54 years become an extension of my arms I've got to try that with a 150 grain Nosler Partition. Not that I really need it because I've got the magnum territory pretty well covered with both a 7 RM and a Mark V .300 WBY, but I think it would be cool to take an elk or a Nilgai with a .270 Winchester.

I'm running 60.5gr of RL26 under a Sierra 160gr SPBT in my 22 inch barrel 280 Rem Ruger M77 MarkII at 2975fps. Accuracy isn't outstanding, but it will print an inch or slightly less at 100yds.

I gotta get me some of that RL-26
I gotta get me some a that RL-26. I've got a .280 Remington too so I want some. That's 7 Mag velocities right there. And my .280 is built on a ratty old 98 action and it has a 26" E.R. Shaw Heavy sporter barrel on it. It only has a 1:10 twist, but that will stabilize 160 grain bullets all day long.

RL26 with a 150 Partition in a 270 is pretty amazing. Right up there with 7 mag numbers. I've come to think of them as close to interchangeable. My SIL really wanted a 270 so I sent him mine knowing I had a 7 mag available. (Thanks Brother!)

I am 62 years old. I bought a Rem 700 7mm Mag about 15 years ago. It was a used ADL model. The guy I bought it from said he had it for a long time and no longer hunts. I hunted with it for about 10 years. I like the 7mm Mag. I killed my share of Deer and Hogs with it. needless to say it drops em like a rock. But I could not get that rifle to shoot less than 1" @ 100 yds. Factory ammo or handloads. And I shot many different load and bullets. A few years ago I had the action trued, trigger tech special trigger installed, re-barreled it with a SS Bartlein barrel chambered in 280AI. It now shoots bugholes @100yds.