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Anyone chronograph their 7mm rem mag loads

43K views 39 replies 35 participants last post by  Darkker 
#1 ·
Hi All,

I'm looking at trading my 270 winchester for a 7mm remington magnum. After a lot of research many people state that the velocities in loading manuals are way over the top and not acheivable. Even on the barnes load data site http://www.barnesbullets.com/information/load-data/ it has the 270 win with a 130 grain at 3133fps and another load at 3211 fps where the 7mm mag with a 140 grain load only travelling at 3107fps and another load at 3145fps. So why would I trade the 270 for the 7mm rem mag? In the manual I have it states the 7mm mag at 3340 fps with RE-22 for a 140 grain load out of a 24 inch barrel.

So I'm looking for actual, no BS chronied loads people have got with their 140 and 160 grain loads in the 7mm rem mag. Also if you could state the powder your using for that load and barrel length.

Thanks
Rick
 
#2 ·
Basically the 7mm Rem offers little performance increase over the .280 Remington which in many ways is virtually identical in performance to the .270 Win. I'll repeat your question, "Why would you want to trade a .270 for a 7mm Remington?" I made extensive comparisons among cartridges in this class 40 years ago, literally 1968, and reached the conclusion then that the best of what I was looking at was the .280 Remington. At best you will see a 100 fps advantage with the 7mm Rem. at the cost of using a lot more powder. At practical hunting ranges you won't see any perceptable gain from this small velocity increase.
 
#3 ·
I've been loading for my old hunting partners 7mm Rem mag for more than 20 years now and were getting published velocities or even a little more with two different Savage 7 mags with both 140 and 175 gr bullets. Recoil as much as I can tell is about the same as a 30-06. He's killed a pile of deer and elk with them.

He doesn't shoot the 160's as he likes Speers 175 grand slams for elk. For long range mulies and white tails he shoots 140's. I'm hesitant giving you his loads as you should work up your own. I can say that a chronograph really helps. You might check our loadswap section by clicking the tab at the top of the page.
 
#4 ·
My 7mm is a funny duck. It shoots 130 grainers about the same speed as it shoots the 175 grainers. :)

I guarantee you can meet or exceed published data velocities with H870 and similar powders when shooting 160 and 175 grain bullets.

I have some 162/168 grain match bullet loads that I made with H870 that regularly exceed 3000fps.

Same for the 175 grainers. 2900-2950 is easily attainable with this powder.

That said, I wouldn't trade in a .270 for a 7mmRM, unless you were going after bull elk and somehow felt under gunned with 150 grain .270 loads.
 
#5 ·
What are you going to shoot? I wouldn't bother for deer / hogs and the like. Elk, well, if I wanted more punch than a .270, would probably move clear to a .338 Win Mag.
 
#6 ·
My 7Mag is an old Ruger tang safety model. With RL19 and a 145 Speer spitzer I get a consistent 3110 fps and 3/4" groups at 100 yards. Pushing a 160 Speer Grandslam hard as I care to I get 2990fps. This is in a 24" barrel. I have been working with my dad's Winchester 70 270 for an elk hunt with the 160 Nosler Partitions. It has a 22" tube and have gotten 2790 with IMR 4831 groups are around 3/4".
 
#7 ·
Here are my Chronograph loads, hope they make sense to you. It is an old custom rifle with a new 26" Douglas barrel.

7MM Rem Mag Speer130gn SP H4831 64.0gn CCI 250 2880fps<?xml:namespace prefix = o ns = "urn:schemas-microsoft-com:eek:ffice:eek:ffice" /><o:p></o:p>
7MM Rem Mag Hornady154gn SP H4831 57.5gn CCI 250 2603fps<o:p></o:p>
7MM Rem Mag Sierra 168gn HPBT Match King H4831 59.7gn CCI 250 2629fps
 
#34 ·
The H4831 is known for reduced velocity, as much as 200 fps over IMR 4831. Try the newer powders especially the 7828SSC. I load 63 grains IMR4350 pushing 140 Grain accubonds consistently between 3143 & 3149 fps. When I go to 65.5 grains I'm moving at 3260~3267 fps. both giving 1/2 groups. But, I do have to re-sight when going to the heavier load which shifts slightly up and 1 moa horizontally right of the slower loads. That is a natural thing to occur.

Go to the RL22 and I'm now up into 3338 FPS. Great cold weather round if you like hot.

i shoot nothing but Sendero's.
 
#9 · (Edited)
I recently tried -
64 grains RL19
Win Primer
168g Berger VLD
Through an older Rem 700 w/22in barrel and averaged 2836 fps (5 shots).

High - 2855 fps
Low - 2819 fps

With very nice,tight little group. Although the primer seems a little flattened. I back down to 63 grains and had the same results with primer,
and 2801 fps.

Then tried 65.5g RL22, same result on primer,and 2786 fps.
 
#10 ·
Even assuming loads do measure up to published specs there is just not a great deal of difference between a .270, 30/06 and a 7 mag. We gun guys like to split the hair mighty fine but does the critter on the receiving end know the difference? I really doubt it.
 
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#11 ·
I guess I'll split the hairs. Owning, reloading and shooting both calibers, I just don't see them as being as close as some. If you compare 'apples to apples' bullet wise, there's a pretty big difference between the two. We're talking 300 fps muzzle velocity and at 200 yards, there's close to 1000 lbs energy difference. A velocity difference like that is like comparing the .308 to the 300 Win Mag, but even the 300 mag doesn't have the energy spread the 7mm Mag has over the .270. I think the best argument is that if you're a reloader, you can load the 7mm Mag down to close to the .270, but you're never going to load the .270 up to the 7mm Mags potential, no to mention the 7mm can shoot the heavier bullets.

Having stirred the pot, my work here is done...:)
 
#12 ·
With the lighter 7mm bullets, the 7mm Mag is just a loud mouthed .280. The .280 and the .270 could not be told apart by shooting them, or by their effect on game. That includes, in my experience, the actual chronographing I have been able to do with all those rounds.

With heavy for caliber bullets, the 7mm Mag will do things the .280 or .270 cannot do, but the differences are not dramatic. If I found myself wanting more than a .270 can manage, I would jump farther than the 7mm Magnums and go to at least the .300 magnums for the much heavier bullets. A .300 Win. Mag with 200 grain bullets is an indisputable elk/moose rifle.

Truth is, however, that the .270 will do it too if you are careful. So my measurements of the few rifles and loads that I have actually been able to test have me thinking the move from .270 to the 7mm Rem Mag is more sideways than up.

One last consideration: I have come to dislike belted cases. The .270 isn't one; the 7mm Mag is. Just another reason to not make that particular move for me.
 
#13 · (Edited)
I sold my semi custom M700 7mm rem mag rather quickly after about a years worth of trying to make the loads hit magnum performance..I also owned a M70 featherweight in 280 that sported a 22" barrel.

Resullts with the 7mm mag,
140 nosler BT 2950fps MAX loads , This was the average with a number of different powders.
150gr bullets same reuslts.To be honest I couldnt get anything to break 3000fps with out showing high pressure signs .As I said, I used a number of different powders and bullet depths ,primers etc. pretty much stayed withing 50-100 fps with all the variations with bullets that ranged from 140-175.Matter of fact I saw this mentioned above.I got d***n near the same velocity with the heavier bullets as I did with the 140 grn bullets out of my 7mm mag.


My 280,
hahhaha 139 hornady BTSP 3,050fps.

150 gr sierra bt right under 3000fps ,2970 on average

I believe I got this all with H4350 , I could be wrong though.I dont have my logs with me here in Iraq but I do remember that I passed up the 7mm mag with the 280 or came in with the same numbers,The reason I sold the loud slow magnum.Butv I will say that with the heavier bullets the 7mm mag had about a 150-200 fps advantage even though it couldnt spit the 140s out faster that the 175s or 160s,nor the 280.


All in all the 7mm rem mag is a hit or miss rifle when actually trying to achieve magnum perfomance.It does shine over the 280 and 270 with a 26" barrel with heavier bullets.But if you are looking for a rifle of reasonable carrying weight and a shorter 22-24" barrel.You can neck size those 280 or 270 cases to get a little more case capacity and run the 7mm mags heels rather easily with the 130-150 grn bulets.

BTW,accuracy was very good in both rifles/calibers.The 7mm mag best groups were 3/8" at 100yd with the 140gr ballistic tips.The best groups with the 280 were right at 5/8" with the 150 sierras.

Just my personal experiance.
 
#14 ·
Thanks for all of the input guys. I think I'll keep the 270 after all of the discussion. They are pretty close and I only would need a 140 grain projie out of the 7mm rem mag. The diff between the that and the 130 grain 270 load seems pretty minimal.


Cheers
Rick
 
#15 ·
The reason for similar performance between 270 and 7mm is that SAAMI pressure
specs for the 270 are several thousand higher than the old old 7mm rem mag.

So, higher pressures offset extra case volume. How is it that the non belted
270 case can tolerate higher pressures then the belted magnum 7mm I dont know.

It makes me think the 7mm could be loaded hotter like other magnums
but then again I read others accounts of hi pressure signs so I dont know.

In any case, by virtue of allowed pressures, the 270 has more right
to the magnum nickname than the 7mm. The 270 is in the same
league as all the other magnums but the 7mm is in the league with
lower pressure cartridges.
 
#16 ·
I get 3000 fps with a 130 gr bullet, 56.5 gr of IMR4831 with my 22" barrelled 270. With a 24" tube, I'd probably get 3050 - 3100 fps.

I should be getting 3000 fps with a 160 gr bullet and 63.0 gr of RL-22 with my new 7mm RM's 24" barrel. I'm getting 2875 fps.

The 7mm is a good cartridge, but any difference between it and the more efficient 270 or 280 Rem. is completely insignificant.
 
#18 ·
7 mm is a great deer/elk/moose calibre

Here is my finding. First any good rifleman knows that a well placed average speed shot is better than a poorly placed smoking hot shot. So my first thought is this: Find a loading that suits your shooting style and forget the high power, high speed, heart thumping, drama creating loads. Personally I have chronographed my loads at 2825 FPS but have first class accuracy with a trajectory that is easy to remember. Here is my load information and the results at the target. 160 Sierra BTSP bullets, 65 grains of IMR 4350 Powder, Federal 215 primers. RESUTS: .5" groups at 100 yards shot from a Smith & Wesson model 1500 with a 24inch barrel. I purposly set my sights 4" high at 100 yards. This gives me 5"high at 200 yards, dead on at 300 Yards, 12" low at 400 yards and 24" low at 500 yards. These are real results from a chronographed load and many days at the range.

So think about this for a minute. Since North American Mule Deer are about 24" deep from the top of the withers to the breast bone. This means that a decent shooter can aim in the middle of the body mass of a deer (or elk) right out to 350 yards and be sure of a killing hit.

I like this load. I have killed a dozen or so deer (both mulies and white tails) and several elk with this load. If I do my part and place the shot well the meet will be on the table. I have only had one failure to drop imediately. On inspection after locating the deer several hundred feet from where it was shot it was found that the shot hit the shoulder bone and fractured the bullet, sending several shards of schrapnel into the carcass, one of which hit the liver killing the deer. This deer was shot at 300 yards. I have shot several at less than 25 yards and they dropped like a sack of spudswithout lifting a hoof.

My recommendations is this; Try several loads, have fun, find one that you like, stick with it, and learn how to shoot it well at all distances.
 
#19 ·
I personally think the .270 is one of the all time great cartridges, just like OL' Jack used to say....it will, and has, regularly killed everything on the North American Continent, reliably. Why change ? if you must have more Whoom and Blast get something big enough to make a real difference like a 338......
 
#20 ·
After reading the previous posts, I must say that my experiences with the 7RM is quite different from most of the previous posters. Having said that, I must also state that my experience reloading the 270 Win is limited to one rifle, a friend's from close to 20 years ago so I can't recall much of the loading results accurately. However, I've been loading for the 7RM for over 20 yrs.

My first 7RM was a Sako hunter with the barrel length stated in metric. Converted to standard measurement, I think it was around 23". It shot the old 162 grain Nosler Solid Base bullet just over 2900 although this is from memory as that load data is long gone. This barrel lasted approx. 3000 rounds then was replaced by a 24" Shilen which I loaded with 150 gr NBT at 3150-3170 over the chrono. This barrel lasted around 2500 rounds before being replaced, this time with a Ron Smith 25" barrel. The load again was the 150 NBT at an averaged 3163 fps.

My current 7RM is a L61R action and 26" Hart barrel in a Harry Lawson Cochise stock. The load is the 168 Berger VLD at an averaged 2954 fps with RETUMBO and WLRM and WW Super cases neck sized only. According to BOTW, their load, with some 3 grains more powder achieves approx. 3050 fps with the same bullet.

I shot only a few deer and one antelope with the early 162 Solid Base but have shot 20-30 deer with the 150 NBT, 5 or 6 moose and probably the same number of antelope as moose. This past season, I shot 4 deer with the VLD. I realize this is not extensive experience compared to some but it has served to provide a reasonable conclusion of what the 7RM will do. The furthest and closest shot animals were both moose, one at 15-20 yds and one at a lasered 452. The close ran off and was found 30-40 yds away and the far moose dropped where he stood. Both were shot once. Sometimes it just happens that way. Over the years, I've lost one game animal, a WT buck shot at 15-20 yds with a Texas Heart shot and the NBT. Not the shot I attempted but the bugger was rattled in and sensed me and whirled just as I shot.

Check the energy differences between a 130 270 at 3050 and a 168 7mm at 2950 fps. It's then difficult to say they're pretty much of the same horsepower. Nonetheless, I recognize they're both similar in the practical sense on deer but not so on moose, at least not at longer ranges. Certainly the recoil of the 270 is less than the 7RM and that should be considered when choosing which of the two cartridges in a new rifle. In fact, my 168 VLD load was to go with me this March to Namibia for PG but an eye surgery cancelled that trip. For next season's deer, I intend to develop a 140 VLD at 3000 fps. Oddly enough, this should closely equate to a 270 140 load. But, as I stated earlier, for deer, there's no practical difference between the 270 and 7RM; ditto for the 280.

Bobby B.
 
#21 ·
I shoot a 7mmRM Model 70 Classic w/ a 24" bbl. My load is a 139gr. Hornady bullet and a lot of Reloader 22. In my rifle, it goes through the lights at 3150 fps. Not particularly impressive, but it shoots 1/2" groups at a 100 yds., so I like this load! I agree with other posters, in that the 7mmRM probably starts to shine with heavier bullets. IMHO, a 7mmRM will do with a 140 gr. bullet just what a 270 Win will do with a 130 gr. slug. Not a big difference, but us rifle loonies are always looking for an edge! BTW, for those who like to condemn belted cases, don't you know that cartridges with belts are now the new classics! :D:D:D With the advent of the wide bodies, the belted cases have now been sainted! :D:D:D
 
#22 ·
Gents,

Agreed. I think that my light bullet loads have averaged in the 3100 range, and it can be difficult to get there. As this was not where the data advertized they ought to be, it was a bit of a let down for me when I arrived at this. It does stand question for a case that burns 10 more grains of powder more than a 270, generates more blast and recoil, and just shades its velocity.

I did get the advertized 3300 fps with one lot of 139s loaded with Winchester Magnum Rifle, on a day that was frightfully hot. These loads got back in the 3150 range when the temperture was in the 50s.

I've since started shooting the heavier bullets, and am really confining study of this rifle to long range target work, and specialized hunting application. The 168 Sierra averaged 2850 thereabouts, and are exceptional accuracy wise. They also are one of the bullets that I have found "go to sleep" past 100 yards, the 200 yard group will be roughly in the same size/ shape as the 100 yard groups, and does this consistant enough time and again, and on a few different ranges, so I know its not me. I did switch to the Federal 215Mag primer, and that is also showing promise.

I think this cartridge can be a bit tempermental, and takes a little dickering to get sorted out. I think this is mostly a function of the case length restrictions, and sorting out the right bullet weight with powder burn rate. Working it out does give a man something to look forward to though, doesn't it?

Best to you fellers.

Steve
 
#23 ·
im not going to attempted to learn another mans game ,at my age.. fusion 165 does it for me..
but you guys talking this stuff in plain terms sure gives us without the knowledge a
glimpse of the work you do..old shaky hands would over load grns of some super powder an
blow his eyes out ..but its nice knowing how some of the commercial rnds came to be..
i know they have to be safe.. sami or what ever.. i enjoy reading it.. slim
 
#25 ·
I'll chime in and try to offer a synopsis of the difference between the .270Win and 7mm Rem Mag.

In bullets of 150gr or less, they are too similar to make a case for either being superior. In lighter bullets, the 270 is far more efficient and with heavier bullets, the 7RM offers significantly higher BC and retained energy. For black bear and smaller, the 270 is great...hard to beat with any caliber, really. However, if bigger bears and bigger deers (elk or moose) are on the menu, the 7RM will make good use of the increased case capacity, so long as you have a longer barrel to develop those velocities.

This is pretty standard stuff, and while I am an unabashed proponent of the .270Win, I recognize the 7Rem Mag as superior, when loaded in long tubes, with heavier bullets.
 
#26 ·
unless you are shooting a bullet 150 grains or better out of a barrel 24 inches or better at a target at 300 yards or farther the 7mm has no advantage over the .270, so unless you are after elk or the like stick with the .270 the 7mm only really shines past 400 yards with a 26 inch barrel and a 165 grain or larger bullet.
 
#27 ·
150gr nosler ballistic tips x64grs 2213sc(h4831)--2965'/sec.-approx 3/4" 160sierra bthp gamekingx73 grs of 2225(retumbo)-3050'/sec av-approx1.25"group at BEST-hunting load.-dont like to use under 160 as they dont work effiecient enough to be of much more use than a hot loaded 270.--160 upwards and you can tell the difference. i like the 7mm as i can load it mildly and still equal a full powered 270 load.personally i use the 7mm as a jump up from the 25/06 and if i owned a 270 would not even think of a 7mm mag.if i were you and you were looking for more weight,i would choose a 338 winny.if you want weight and flatness,try any of the larger 30 cals.
 
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