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I can get better than 3200fps out of my 7mag with a 140gr bullet.As far as recoil goes,with the right recoil pad such as Limbsaver,it's not bad at all.The problem with comparing todays published data on the 7mag is,it's been loaded waaaaaaaaaaay down to make the more recent larger 7's look a lot better.My older manuals are right on with max loads and velocities as compared to most of the new ones these days.The 7mag is as good today as it was when it was first produced,only the loadings have been changed.
~Molɔ̀ːn Labé Skýla~
As Bob Hagel would say"You should not use a rifle that will kill an animal when everything goes right; you should use one that will do the job when everything goes wrong."Good words of wisdom...............
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The problem with comparing todays published data on the 7mag is,it's been loaded waaaaaaaaaaay down to make the more recent larger 7's look a lot better.My older manuals are right on with max loads and velocities as compared to most of the new ones these days.The 7mag is as good today as it was when it was first produced,only the loadings have been changed. I don't know that the reason was to make the newer 7's look better. There was the STW and maybe a couple of others, but before a lot of the new-fangled 7's had come out, I read in one of my manuals 10+ yrs ago or more that the reason for the lower velocities at high pressures was due to shorter throat length. There was a push to seat bullets closer to the lands for better accuracy and therefore the chambering was different. Some of the older models, according to them, had longer throats and the older data reflected that. They attributed some complaints of people being that the rifles used by them to compare data perhaps had significant throat erosion. Accuracy had not been effected appreciably as these are mostly hunting rifles. Incidentally, my 1964 Lyman manual shows about 3 gns hotter for the 30-06 than the later manuals as well. I can't use that old data in my rifle. Powder lots change and what not. Old manuals become, therefore obsolete.
Steve
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The SAAMI psi numbers for the 280 and 7RM are 60,000 and 61,000 respectively.
Max average.
Do you guys know what they placed the 280AI at--was it 65,000? I don't think that SAAMI has published data for the 280AI, at least from what I've gleaned. However, the limiting factor for chamber pressure is not so much the action, but the cartridge's case head, i.e., the area where the brass is no longer supported by a surrounding chamber. Therefore, the limiting pressure should be the same. Besides a slight addition in case volume, where the AI's shine is that the case's minimal taper passes more of the rearward thrust into the chamber walls, or so I've heard. That helps to prevent case-stretch and therefore case-life is prolonged.
Steve
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dcralston......I think you are confusing some cup numbers with psi numbers in that example .
Gunslinger,
You are right. After rechecking the manual it does have the 280's cup pressure and then for the 7rm it shows the pressure in psi.
Just for my own info what is the difference between the two and why would a manual show the cup for one caliber and the psi for another? As a beginning handloader what would the cup # do for me.
Thanks
"It is better to keep your mouth shut and appear stupid, than to open it and remove all doubt." -Mark Twain
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Campfire 'Bwana
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Day in and day out the 7RM is faster across the board if both are operated at the same pressures....in general 7RM will move a 160 gr bullet at the same velocities a 280 will move a 140,as a general rule.And a 7RM will outrun the 280 pretty easily with the same bullet weight.By how much depneds on how hot you choose to load each catridge, what barrel you are running, etc etc.
I always looked at the 280 much the same as a 270,a cartridge for a light and lively mountain rifle weighing in the 7-7.5 pound range with a 22" barrel;and the 7 mag weighing a bit more with a 24"+ tube. If I'm gonna lug a 24" tube I would just as soon have the magnum chambering and take advantage of the additional powder capacity.
Differences in recoil between them are pretty moot to me,as even a heavily loaded 7RM's recoil is trifling....this has always been one of the cartridges greatest virtues.
The 280 Remington is overbore.
The 7 Rem Mag is over bore.
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dcralston......I think you are confusing some cup numbers with psi numbers in that example .
Gunslinger,
You are right. After rechecking the manual it does have the 280's cup pressure and then for the 7rm it shows the pressure in psi.
Just for my own info what is the difference between the two and why would a manual show the cup for one caliber and the psi for another? As a beginning handloader what would the cup # do for me.
Thanks Many of the good load manuals will have a better explanation than what I can do , but basically CUP numbers are obtained by the old copper crusher method , while PSI numbers are gotten by a piezeo-electric system or a strain guage . There is ROUGHLY ,( assuming we are talking about high pressure bolt rifle loads ) about 10,000 difference in the numbers of the same load between the systems , with CUP being the lower of the 2 . But , for the most part , you cannot directly convert CUP numbers to PSI numbers . As to why some load books show CUP for some calibers and PSI for others , I really don't know , but maybe the work was done in different labs or at different times . Many of the more obscure calibers will be listed with old data that was done years back with the copper crusher system . To top it off , back in the day when old codgers like myself or BobinNH started loading , there was only the copper method , so the numbers were commonly quoted as simply PSI , when they were really today's CUP . All clear as mud now ? (grin)
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Thanks, I appreciate the info!
Dave
"It is better to keep your mouth shut and appear stupid, than to open it and remove all doubt." -Mark Twain
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The big 7 can handle heavier bullets better at higher velocities than the .280. You would have to red line the .280 to achieve what the 7 can do easily.
They're both good rounds but folks that say the .280 will do what the 7mag will are misinformed.
Aim for the exit hole.
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Campfire 'Bwana
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All clear as mud now ? (grin)
Yup! 
The 280 Remington is overbore.
The 7 Rem Mag is over bore.
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Yeah, IIRC read somewhere that it was going to be 65--maybe that was MD--can't remember. I was going to call Nosler to see what their loads were at, but haven't got around to it.
+1 Bob on the recoil. Run an AI about a pound lighter and the kiss is the same.
Defend the Constitution
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I like the 280AI over the 7mag with 140grain boolits. Mine runs 3206 from a 24 3/4 tube. very 7magish without the 7mag recoil. If heavier boolits are your thing then the 7mag takes the cake.
Crossed Arrows Archery LLC Authorized Obsession Bows Dealer Custom Strings/Tuning www.crossedarrowsarcheryllc.comBlack Eagle Arrows Pro Staff, Montana Black Gold Shooting Staff, Dead Center Archery Products Shooting Staff
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Skywalker: I own and Hunt with both calibers (the 280 Remington and the 7mm Remington Magnum) and have for MANY years!
I have never personally had anything to do with a 280 Remington Ackley Improved.
NO, I can't make my 280 Remington do what my 7mm Remington Magnum does.
Normally I don't Hunt Elk and Black Bear with my 280 Remington BUT in the past I have killed BOTH of them with the 280 Remington!
A lot of Moose country (even here in SW Montana!) IS Grizzly country!
For Moose (and MAYBE for Grizz!) the 7mm Remington Magnum should be your choice.
I have even Hunted Antelope with my 7mm Remington Magnum and lighter bullets - its a fine Antelope round, shooting FAST and flat!
Expand your horizons and consider the flatter trajectory of the 7mm Remington Magnum for when you go Caribou Hunting, Bighorn Sheep Hunting, Mt. Goat Hunting and the aforementioned Antelope!
Learn to deal with the somewhat increased recoil and the somewhat decreased barrel life of the 7mm Remington Magnum.
I did.
Best of luck with whichever you choose.
Hold into the wind
VarmintGuy
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Varmint Guy I agree! Unless you deliberately perch on open hillsides with your buddies near the pickup,Sony's whirling for the next episode of Western Extreme,and CHOOSE to take 700 yard shots,most game is taken at well under 400 yards,even in the west.... It may not be in vogue today,when flat trajectory is treated like a social disease,but a 140 gr 7mm bullet started at 3200+ fps(whether we get it from leaning on an AI a hair,or do it rolling over easy-like from a 7RM),is a fabulously useful tool,requiring nothing for holdover to 350 yards or so on deer/antelope-type game..... This is especially useful when the mule deer is of trophy grade,especially skittish and not offering enough time to deploy the Leica 900,because you have already been "had"....or that rut-crazed whitetail that decides to hustle across a broad field or cut line,offering about 5 seconds to "get 'er done". Fast-moving 140 7mm's are among the best for this sort of thing; trajectory is flat,the load is hard-hitting,and does not kick you into next week... BTW, I am no grizzly expert, but I would not hesitate to hunt grizzly-invested elk country with a properly-loaded big 7; it has been done many times before... 
The 280 Remington is overbore.
The 7 Rem Mag is over bore.
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I have hunted with both cartridges,(they are they are the same caliber by the way ),and I am now doing all of my big game hunting with the 280AI.My 280AI rifles drive the 140gr TTSX at 3170fps,which is actually faster than most 7mmremmag 140gr factory loads,and it works just fine on moose and elk.
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Varmint Guy I agree! Unless you deliberately perch on open hillsides with your buddies near the pickup,Sony's whirling for the next episode of Western Extreme,and CHOOSE to take 700 yard shots,most game is taken at well under 400 yards,even in the west.... It may not be in vogue today,when flat trajectory is treated like a social disease,but a 140 gr 7mm bullet started at 3200+ fps(whether we get it from leaning on an AI a hair,or do it rolling over easy-like from a 7RM),is a fabulously useful tool,requiring nothing for holdover to 350 yards or so on deer/antelope-type game..... This is especially useful when the mule deer is of trophy grade,especially skittish and not offering enough time to deploy the Leica 900,because you have already been "had"....or that rut-crazed whitetail that decides to hustle across a broad field or cut line,offering about 5 seconds to "get 'er done". Fast-moving 140 7mm's are among the best for this sort of thing; trajectory is flat,the load is hard-hitting,and does not kick you into next week... BTW, I am no grizzly expert, but I would not hesitate to hunt grizzly-invested elk country with a properly-loaded big 7; it has been done many times before... +1 I have a preference for shooting heavier for caliber bullets and prefer the 175 grainers most of all in this caliber. All my 7mm RM mags have 26" tubes. As One Minute pointed out, if the throat is long enough to seat the bullet out to where the base of the bullet is flush to the bottom of the case neck and the magazine length is long enough, the personality of the 7 mm Remington changes considerably. You are starting to think about the 7mm Mashburn now! JMHO
Men ocassionaly stumble over the truth from time to time but, most pick themselves up and hurry off as if nothing happened.
- Winston Churchill-
NRA Endowment Life Member
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Campfire 'Bwana
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.....(they are they are the same caliber by the way )...... This is true!
The 280 Remington is overbore.
The 7 Rem Mag is over bore.
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Campfire Outfitter
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I've hunted with both. I now have 2 280's and no 7 mag. I may own another 7 mag in the future, but don't feel that I'm lacking.
Broncos are officially the worst team in the nation this year.
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Skywalker: I own and Hunt with both calibers (the 280 Remington and the 7mm Remington Magnum) and have for MANY years!
I have never personally had anything to do with a 280 Remington Ackley Improved.
NO, I can't make my 280 Remington do what my 7mm Remington Magnum does.
Normally I don't Hunt Elk and Black Bear with my 280 Remington BUT in the past I have killed BOTH of them with the 280 Remington!
A lot of Moose country (even here in SW Montana!) IS Grizzly country!
For Moose (and MAYBE for Grizz!) the 7mm Remington Magnum should be your choice.
I have even Hunted Antelope with my 7mm Remington Magnum and lighter bullets - its a fine Antelope round, shooting FAST and flat!
Expand your horizons and consider the flatter trajectory of the 7mm Remington Magnum for when you go Caribou Hunting, Bighorn Sheep Hunting, Mt. Goat Hunting and the aforementioned Antelope!
Learn to deal with the somewhat increased recoil and the somewhat decreased barrel life of the 7mm Remington Magnum.
I did.
Best of luck with whichever you choose.
Hold into the wind
VarmintGuy Sorry for digging this out, but what do you exactly mean with decreased barrel life of the 7mm Remington Magnum. When does it really matter? I recently aquired a Rem 700 BDL in 7 mm Remington Magnum and would like to know more about my new hunting buddy. How can I avoid the decreased barrel life you are talking about?
Elmer Keith
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The mag pushes more hot gas through the same size hole, so it will generally erode the steel faster. With that in mind I wonder why the mouths of politicians don't wear out faster.
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Campfire 'Bwana
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Elmer, I would not worry my head about it as they make plenty of 7mm barrels in the event you are lucky enough to wear one out from too much shooting The fastest I have had a barrel go was a Shilen chambered for 280,in about 600 rounds(!);that was very unusual and your 7 mag could likely go a couple thousand before it quits...it all depends but the point is don't sweat,just shoot and enjoy it.It can always be replaced.
The 280 Remington is overbore.
The 7 Rem Mag is over bore.
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