effeciency in a case like 7 mag

WhelanLad

WhelanLad

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hey fellas i been chatting 7 rem mags with yas on here a bit and you all set me very right an appreciate that.

in regards to powder, burn , amount usage etc, which powder is the most effecient in your opinion?

Yaa see, my 708 takes 40grains, to spit a 140gr around 2700 -2800 range, which i think is very effecient?!

then i have this Rem Mag with a big belly for powder, pending how slow of a burn rate depends on how much grains go in the case.

ADI 2213sc - 64gr max
ADI 2217 - 70gr max
ADI 2225 - 74gr max........

Now the Speeds vary considerably from each max to another, so could be more if the gun isnt running a max charge for accuracy etc...

Now i was worried about getting that FPS wit hthe slower 2217 powder, however im putting quite alot more powder in to it to gain the 100-200fps pending, and the more i think about it, the more efficient the AR2213SC seems?

less grain per shot, more shot per cannister , less cost to me....?

minus some FPS which I've sort of worked around with the use of the "Dial" scopes....

Is this on the right track ya rekon?
 
Well, when choosing a load, the accuracy is the primary objective. The second would be the flatter trajectory (MV) and then other factors such as the kick, component availability....
Price difference between different reloads is only a couple of cents and its not to be considered.
 
Ariu said:
Well, when choosing a load, the accuracy is the primary objective. The second would be the flatter trajectory (MV) and then other factors such as the kick, component availability....
Price difference between different reloads is only a couple of cents and its not to be considered.
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aw thats debatable with some of us folk who may shoot a fair more than average, or where the government decides to tax everything before it lands, then taxes it again when its sold, lol,

i understand some of what ya getting at, an i guess it is true, there is too many variable opinion on the matter of what cost is, alone, to make it valid.

hmm.

we will just agree the 7-08 is most effiecient of those :)
 
WhelanLad said:
aw thats debatable with some of us folk who may shoot a fair more than average, or where the government decides to tax everything before it lands, then taxes it again when its sold, lol,

i understand some of what ya getting at, an i guess it is true, there is too many variable opinion on the matter of what cost is, alone, to make it valid.

hmm.

we will just agree the 7-08 is most effiecient of those :)
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Don't forget the whole reason you bought the 7mag! You wanted a worthwhile increase in potency from your 7mm08 didn't you? For that reason alone I would be looking towards the powders that are giving you the best velocity while still maintaining acceptable accuracy.

Besides, if you run the numbers the difference between 62gr of powder and 72gr of powder is 15 rounds (112 rounds vs 97 rounds) per pound of powder, or 16% savings on the powder cost. Here, that would probably only work out to about 5-7% in total savings per round once you factor in the bullet/primer costs.
 
Anyone who ever read Jack O'Conner stories about the .270 Winchester should know the .270 Win is the worlds best non-belted magnum. :evil:

The problem is with the 7mm Remington magnum you need a 26 inch barrel to get the most out of the cartridge and case capacity. :stirthepot2:

Jack O’Connor with one of his last rams, taken with his famous Biesen-stocked “No. 2” .270. O’Connor was the undisputed champion of the .270 Winchester, but from the standpoint of years I have to agree he was right!

oconnor.jpg


7mm Remington magnum................Bah humbug.
 
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Interesting. My take on it:

How much velocity do you need?
Depends on the bullet. For hunting, the we need good expansion, and the manufacturers recommend a minimum velocity.
I’m using Barnes TTSX, 150 grn. I looked into the minimum velocity a couple of years ago, and I’m confident that I’m good to 500 yards. I would never take a shot that long.
These bullets are expensive, but I’m getting reliable one shot kills, at 200-330 yards. I always go for the double lung shot.
I shoot mostly off a bipod, preferably prone.
I don’t mess with dial scopes, but use the maximum point blank range approach.
Just my 2 cents worth.
I did buy some Hornady Interlock bullets for practice at 1/2 the price, but haven’t developed a load for them. Maybe once hunting is over. I was trying to develop a load for a new rifle in 308, but haven’t found a decent, accurate load yet.
BTW increased velocity means increased recoil, as I’m sure you know. Shooters vary as to how much recoil they can tolerate.
Will be hunting this morning, as soon as there’s eneough light. Bit of fresh snow overnights probably changing to rain late morning.
 
Leatherstocking said:
Interesting. My take on it:

How much velocity do you need?
Depends on the bullet. For hunting, the we need good expansion, and the manufacturers recommend a minimum velocity.
I’m using Barnes TTSX, 150 grn. I looked into the minimum velocity a couple of years ago, and I’m confident that I’m good to 500 yards. I would never take a shot that long.
These bullets are expensive, but I’m getting reliable one shot kills, at 200-330 yards. I always go for the double lung shot.
I shoot mostly off a bipod, preferably prone.
I don’t mess with dial scopes, but use the maximum point blank range approach.
Just my 2 cents worth.
I did buy some Hornady Interlock bullets for practice at 1/2 the price, but haven’t developed a load for them. Maybe once hunting is over. I was trying to develop a load for a new rifle in 308, but haven’t found a decent, accurate load yet.
BTW increased velocity means increased recoil, as I’m sure you know. Shooters vary as to how much recoil they can tolerate.
Will be hunting this morning, as soon as there’s eneough light. Bit of fresh snow overnights probably changing to rain late morning.
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100% mate, im already tip toeing on the line of my limit, i was hesistant after shootin stout 180 30-06 woodleigh loads, rouemr had it the 7 rem mag is about that, an this gun with pad is sweet with a jumper on etc, so all that is fine, but i agree.... how much do ya need... an how much more recoil do i want.

answer from my end, not much more and none. :)

good idea on the hornady inters,
good luck out there an have a blast. regardless if the gun dont go off
 
Suther said:
Don't forget the whole reason you bought the 7mag! You wanted a worthwhile increase in potency from your 7mm08 didn't you? For that reason alone I would be looking towards the powders that are giving you the best velocity while still maintaining acceptable accuracy.

Besides, if you run the numbers the difference between 62gr of powder and 72gr of powder is 15 rounds (112 rounds vs 97 rounds) per pound of powder, or 16% savings on the powder cost. Here, that would probably only work out to about 5-7% in total savings per round once you factor in the bullet/primer costs.
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Yeah for sure that was a main aim!

i havnt forgot that bit.. an with that math, yeah it really is fook all at the end of the day :)
Thanks, practical man!!

haha cheers mate

Edit---

i guess as the above poster mentions.... the 270......... i can obtain similiar velocitys, with a suitable projectile for the game and alot less pow pow an recoils etc..... no it isnt a brother to the 7mm, but with a long-er tube its seems more effecient than the magnum.. price negatable , but if i start stoking this 7 rem mag in, i can see i wont like it, so it will be a later on poder upgrade now im happy with this load combo etc..
 
You can get decent velocity and accuracy from 4350 speed powders, and use less of it then the 4831 speed powders. Nothing wrong with down loading the 7mm a bit if that velocity range suits your needs.
 
No pun intended, but it's bit of a moving target. As better bullets with increased ballistic coefficients come out, trajectory flattens and performance on game increases. To that end, the 7mm Mauser in a Ruger #1 my son shoots, is no longer the rainbow dog it used to be. With a 162 ELD-X it is a whole lot flatter shooting than it used to be, and the better bullet also extends the range.

Efficiency, to be a criteria for caliber selection, does need some parameters.

BTW I have owned 7mm Remington magnums and a 7mm-08. And yes, a 7mm-08 will shoot a 140 grain bullet at 2800 fps, and use less than 50 grains of powder to do so, a 7mm Remington magnum will need about 20 grains more powder to do that. But a 7mm Remington Magnum will also shoot that same bullet at 3100 fps. In fact a 7mm Remington Magnum will achieve 2800 fps with a 162 grain bullet fairly easily.

Have you ever noticed that when someone is describing their non magnum rifle they will usually say it is an efficient little caliber. "Efficient" and "Little", and I've yet to hear anyone say that their magnum is a efficient big caliber.

The "Efficiency" thing is a red herring of sorts, a way to give a small, low performing caliber some hunting creed. A trolling topic, like stating that the 243 is not a very good deer rifle.

The 7mm-08 is an old design, we can see what a modern approach has done to the 6.5mm calibers. The 260 Rem has been kicked to the curb by the 6.5 Creedmoor.

The 7mm Remington Magnum, in spite of it issues has hung on in popularity. It would be better in 30 caliber, IMHO. In it's day, 7mm bullets had a higher ballistic coefficient than most of the 30 cal bullets. I has some pretty decent velocity claims, but in reality, it has trouble achieving those velocities.

Efficiency aside, the 7mm Rem Mag is a better hunting caliber than the 7mm-08, it shoots flatter, and shoots the heavier bullets with enough velocity to make them effective on the larger bovine species and bigger bears.

And I'd probably pick a 6.5 Creedmoor over a 7mm-08, the Creedmoor seems to work better. IMHO the 7mm-08 was a somewhat compromise design, should have had a different shoulder angle or some other changes to make it work a bit better. You chose a 140 grain bullet in the 7mm-08, I'd rather shoot a 155 in a 308. And a 140 grain bullet is a poor choice in the 7mm Rem Mag, unless you're out to blow up vermin.

In 7mm, I'd pick a 275 Rigby or a 280 Remington over either one of those. If I needed more range, a 270 WSM would be a better choice. If I needed more energy, a 338 Win Mag is a hard one to beat.

And if I could only own 1 rifle, which will be the law soon given the present political storm, it would be a 30-06. It will probably still be under the new Joule level which seems to be that no high power rifle be over 5,000 joules.
 
As I said, I use the 150 TTSX. A heavier bullet gives you a better BC but less velocity. It’s what suits your preferences.
Barnes rates the 150 for elk, but not moose. Lots of people seem to have confidence in lighter bullets in the newer premium bullets.
 
In my 7 mags (five of them at the moment, 7 RM, 7 Wby, 7x61 SH, 7 SAUM and 7 STW.) I use 160 gr bullets, generally. I had some loads with 195 gr bullets, but Barnes stopped making them. As for powders, RL22,25 and 26, IMR 7828 all work well. I use more 22 than anything else, for accuracy reasons. When I want an efficient 7, I look to smaller cases. 7 BR, 7mm-08 and it's Ackley Improved version. FWIW - dan
 
Leatherstocking said:
As I said, I use the 150 TTSX. A heavier bullet gives you a better BC but less velocity. It’s what suits your preferences.
Barnes rates the 150 for elk, but not moose. Lots of people seem to have confidence in lighter bullets in the newer premium bullets.
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Thats silly. If its good for elk, there is no reason it wouldn't work on a moose too.

And you are right, a 140-150gr bonded or monometal bullet are fantastic choices if you want more speed than you can get with the heavier pills. Randy Newberg has killed a lot of elk, and one of his favorite rifles is a 7mm08 spitting the 140gr accubond. He also likes the 308 and 300wm.

For the short time I had a 7mag my plan was to load the 139gr GMX bullet as fast as I could get it to go. I wouldn't hesitate to shoot anything in North America short of bison with that. Now I'm loading the same bullet for my 7mm08, but just shy of 2800fps muzzle velocity only gets me out to like 300-350m before the velocity is getting too low for my liking, the 7mag would stretch that a good deal further.
 
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