7mm STW best loads and advice

Besides the short mag box in the Winchester model 70 I've had good luck with 150 eld x and IMR 7828ssc.
Seating depth in guns having magazines, is always controlled by the magazine length.
Unless of coarse you opt to just single feed it.
I use 162 gr Hornadys in my 7x300 wby on a standard 700 bdl action with seating depth so they fit into the standard magazine. It only holds 2 plus the one in the chamber, but the deeper seating depth does not have a noticeable affect on the accuracy. Again, the 7x300 wby and the 7stw are balisticly clones.
7828 is the powder to use in my opinion, 3400 fps with the 162 isnt unheard of.
 
Seating depth in guns having magazines, is always controlled by the magazine length.
Unless of coarse you opt to just single feed it.
I use 162 gr Hornadys in my 7x300 wby on a standard 700 bdl action with seating depth so they fit into the standard magazine. It only holds 2 plus the one in the chamber, but the deeper seating depth does not have a noticeable affect on the accuracy. Again, the 7x300 wby and the 7stw are balisticly clones.
7828 is the powder to use in my opinion, 3400 fps with the 162 isnt unheard of.


Uffda..........3400 with a 162 and 7828 is really honking on it how much are you stuffing in the case? And do you primer pockets stay tight for over one or two loads? I can't imagine so. Not judging just curious. I love 7828, it's my main powder for my 7 Mashburn Super
 
Uffda..........3400 with a 162 and 7828 is really honking on it how much are you stuffing in the case? And do you primer pockets stay tight for over one or two loads? I can't imagine so. Not judging just curious. I love 7828, it's my main powder for my 7 Mashburn Super
Well it is on the upper end of the velocity scale.
And i dont think i actually said that was the velocity i get with my current load, but i will get more specific.
First off, be aware that 7828 will very abruptly slam the door when the limit has been reached.
So proceed slowly with say 1/2 grain increases till the very first sign of pressue, which is usually a slightly stiffer bolt lift. Even 1/2 gr more might mean a locked bolt with that powder.
I have been as high as 80 grains with the 162 in my gun in cool weather. That load did produce 3400 fps in my gun. Im currently using 78 gr which isnt as critical as for cool weather. Of coarse guns and location as well as temperature can cause differences in results.
We only use these guns for l/r hunting in the fall of the year when cooler weather is the norm.
As for primer pockets, that is the price we pay for max performance if we want it, there is no free lunch.
But thats a choice for each of us to determine for ourselves.
That said i do get 3 or more firings from a case before discarding it.
I only use new or once fired brass for the actuall hunting.
The older brass is used for practice.
 
Thx for your thoughts Yobuck, I see where you're coming from. I've been working with the big 7's (STW, Mashburn Super, 7x300 Wby, 7 Wby, 7 RM etc) for 35 years or so now. Same pretty much for 7828, I do love that powder and have used a couple ton loads of it.

Are you running a 26" barrel, or longer?

That said, we all have our practices and comfort zones. For me, I build a load that I can shoot 365 days a year. For me, if it's a load that works well in the winter but pops primers in the summer then it's time for me to back off. And again for me, if it's a load that's ruining the primer pockets (IE can't keep a primer in them) after 2 or 3 loadings then to me it's way off the charts into the PSI zone and time to back off. For me an extra 100-150 fps or so is just not worth it.

Again, keep in mind this is only my way and doesn't have to be anyone else's. :) so I'm really not trying to school you even though it might sound that way...

I recall the first STW I built, like most I was reading and taking in what Layne was writing back then, think that a lot of us did. Then we got to actually working with them and we sorted out quickly how far out to lunch he was with his speeds!

Long ago I learned that people can make a round do what they want, I'm sure you've seen that as well. Personally I believe that's where the statement that 3400 isn't unheard of comes from. We've heard it before, but IMO that doesn't mean it's a good idea. Problem with a statement like that is that then along comes some speed freak (like I was years ago, I was President of the red liners club for a long time) and they try to do the same thing.

You mentioned that 7828 will abrubtly slam the door, I don't quite concur with that. But, I do feel like most powders/load combo's etc there will be a place that they'll get to where they'll just say "allright, no more quit pushing me"....I saw that a lot with a friend who insisted on getting his, IE pushing his 23-24" 6.5/06's with 140's to the ultimate goal of 3K (pre miracle powders, and to this guy all those zero's was so important), once he would go much over 2850 accuracy went in the toidy and primers would begin to pop (especially in the summer). Again, we use these guns for our year around shooting, so we want one load for all year that'll work on chucks to elk.

Thx much for your time, appreciate it, and I do share your love for the Big 7's, they're so easy to shoot from any position, you can shoot them a lot, and you don't need a brake on them (something which I refuse to own) in order to be proficient with them. Plus they absolutely pound game close and far!

(Sorry to drivel on, this lock down has me going crazy)
 
Thx for your thoughts Yobuck, I see where you're coming from. I've been working with the big 7's (STW, Mashburn Super, 7x300 Wby, 7 Wby, 7 RM etc) for 35 years or so now. Same pretty much for 7828, I do love that powder and have used a couple ton loads of it.

Are you running a 26" barrel, or longer?

That said, we all have our practices and comfort zones. For me, I build a load that I can shoot 365 days a year. For me, if it's a load that works well in the winter but pops primers in the summer then it's time for me to back off. And again for me, if it's a load that's ruining the primer pockets (IE can't keep a primer in them) after 2 or 3 loadings then to me it's way off the charts into the PSI zone and time to back off. For me an extra 100-150 fps or so is just not worth it.

Again, keep in mind this is only my way and doesn't have to be anyone else's. :) so I'm really not trying to school you even though it might sound that way...

I recall the first STW I built, like most I was reading and taking in what Layne was writing back then, think that a lot of us did. Then we got to actually working with them and we sorted out quickly how far out to lunch he was with his speeds!

Long ago I learned that people can make a round do what they want, I'm sure you've seen that as well. Personally I believe that's where the statement that 3400 isn't unheard of comes from. We've heard it before, but IMO that doesn't mean it's a good idea. Problem with a statement like that is that then along comes some speed freak (like I was years ago, I was President of the red liners club for a long time) and they try to do the same thing.

You mentioned that 7828 will abrubtly slam the door, I don't quite concur with that. But, I do feel like most powders/load combo's etc there will be a place that they'll get to where they'll just say "allright, no more quit pushing me"....I saw that a lot with a friend who insisted on getting his, IE pushing his 23-24" 6.5/06's with 140's to the ultimate goal of 3K (pre miracle powders, and to this guy all those zero's was so important), once he would go much over 2850 accuracy went in the toidy and primers would begin to pop (especially in the summer). Again, we use these guns for our year around shooting, so we want one load for all year that'll work on chucks to elk.

Thx much for your time, appreciate it, and I do share your love for the Big 7's, they're so easy to shoot from any position, you can shoot them a lot, and you don't need a brake on them (something which I refuse to own) in order to be proficient with them. Plus they absolutely pound game close and far!

(Sorry to drivel on, this lock down has me going crazy)
Well i dont quite know where to begin.
BUT, might be a good place. Lol
When i decided that glassing the steep ridges of NC PA made more sense than trying to walk around on them,
thereby putting on one man drives for those who had already gotten smart, i knew i needed a better gun.
And at that time most L/R hunters in PA were using 6.5x300 Wetherbys. But, a man named Joyce had recently introduced a 162 gr bthp match bullet that had many of them rebarreling to 7x300 Wetherby. And not long after that the 6.5x300 was dead and buried for l/r hunting.
Untill about 45 years later when the powers at Wetherby decided it was a good idea, and introduced it to the waiting world. The same thing had happened a few years prior when they decided a 30x378, already 40 years old in some places, was a good idea also. But, i digress from the topic.
At that time there were only 2 suitable powders for using in the 7x300 Wby for getting best velocity without stiff bolt pressure. One was H570, a WW2 surplus powder that was difficult to find mainly because of hoarding.
Also the best for the 30x378, which caused much of the hoarding. And by the way it still is the best for that as well as the 338x378. And no i never hoarded any.
The other powder was H870.
In my 30" barrel 89 gr of it with the 162 would produce about 3250 except on very cold days, which was a problem. WC 872 will produce very similar results.
When 7828 became available i was advised to try it, and also advised to be carefull with it due to rapidly building pressure.
I found that 80 gr of it with a 162 was the max that i could use in my 700 action guns.
81gr and i struggle to open the bolt. Even 80.5 makes for a stiffer bolt lift, and this takes place in the cooler weather, which is the only time we use these type guns. We do the vast amount of our practice rock shooting with smaller guns like 308s, and even they have muzzel brakes.
I have 2 7x300 Wbys, one with a 30" barrel, the other has a 26.5" barrel.
The velocity is the same with both guns.
BUT, as for my undying love for the large capacity 7 mms, im afraid i dont have any.
Mind you now im speaking for me, for the place i do my hunting, which is still NC PA.
I built a 7x300 Wby because it produced about 250 fps more velocity, thereby allowing for longer shots than the factory 7 Rem mag i had.
BUT, my longest kill with it has been 1200 yds, and based on those results, i personally think that is as far as i intend using it.
As for the (better) bullets now available, weve found the 162s to need less clicks at 1200 than the 180s do in both the 7x300 and the 7mm Ultra Mag.
BUT arguably at least, the heavier bullets would be better performers at the longer distances.
BUT, there is also the fact that my 300 Norma will produce better velocity with a 190 than my 7x300 will with a 162.
And what it does to a deer at 1200 cant be compared to the 7x300.
Now i did state, (for me where i hunt).
Realize that for the most part we sit on our butts and glass sidehills on the opposite side of valleys.
Over there we might have a 500 hundred yard shot. BUT, over there could be twice that far or even further, and we havent moved anything but our head.
As for the muzzel brake, there is one very important reason for using one. And that is that it makes a big difference in our ability for seeing hits. If we cant see hits, then its best to stop shooting, before maybe the wrong one falls over.
 
Well got it down to 1" group the floating issue was a major concern. Im going to shoot these 140's while i invest in some reloading supplies and maybe try the 150 eldx combo and some 168 long range. Does anyone have a basic reloading set up idea that wont break the bank? I would like to ease into it as opposed to buying everything in sight since I have never reloaded myself?
 
Here is the barrel originally
 

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Picked up an M70 pre 64 rifle that has been re-barreled in 7mm stw. Got a great deal on it the gun is in very good condition and I just couldn't pass it up at a local pawn shop. I am looking for some advice on the best factory ammo available right now just to go shooting until I can get a good load developed. I am new to this blog and look forward to learning from you guys out there. I'm very happy with my recent purchase would just like to make it as accurate as possible. View attachment 182369


first... start off with some nolser custom 160gr accubond ammo for factory it will shoot the best from what I've found!
The brass is really good norma made, get some CCI 250 160 accubond bullets and H1k powder load em to mag box length and let er rip!
 
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Well got it down to 1" group the floating issue was a major concern. Im going to shoot these 140's while i invest in some reloading supplies and maybe try the 150 eldx combo and some 168 long range. Does anyone have a basic reloading set up idea that wont break the bank? I would like to ease into it as opposed to buying everything in sight since I have never reloaded myself?
Buy the Lee kit, it has everything you need to get started to see if reloading is for you, You can upgrade later if you feel the need
 
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