7mm stw vs 7mm rum?

[ncpreacherboy1]

new rifle build project. ballistically these look the same. in you guys opinion, does one offer more than the other?

 

[ol mike]

Their both BIG MEAN 7mm's.

The RUM offer a bit more case capacity.

 

[LewisH]

After studying ballistic and reloading tables, and consulting with Kirby Allen (see his posts on the subject), I decided to go with the 7 STW instead of one of the larger 7 Mags.

Bottom line: the bigger 7s are only recommended if you intend to shoot beyond 800+yrds, or if you just plain like the extra power.

FWIW several threads on another forum suggested that the 7 RUM was more finicky than the 7 STW about loads it shot well.

 

[wildcat]

I believe you can get better brass if you go the 7mm STW route.

W.

 

[HRstretch]

I just love my 7MM STW. I plan on heading to the 300 and 400 yard range tomorrow to check my groups. On paper, IMR 7828 and 150 grn SMK's have been shooting .890 at 300 yards and my H-1000 and 140 grn Accubonds have been just truly amazing on animals. The farthest any animal I have hit with this gun has traveled was about four feet and that was because it stumbled backwards on the impact.

 

[J E Custom]

The big advantage of the 7RUM over the 7STW is with heaver
bullets.

If you intend to shoot 140gr bullets the STW will get within 100
ft/sec of the 7RUM but on 175gr bullets the RUM will have over
200 ft/sec more velocity than the STW.

I like and own both the STW and the RUM and they each have there
strong points.

My best load in the 7STW is a 140 Nozler partition @ 3450 ft/sec.

My best load in the 7RUM is a 160 accubond @ 3394 ft/sec.

I dont find the belt a problem so belt or beltless does not matter
to me.

The 7RUM has a 12% energy advantage over the 7STW and 24% over
the 7Rem Mag with a 140gr bullet and the wildcats blown out with
a 40o shoulder add more case capacity to shoot the realy big
7mm bullets (Like the 190gr).

I hope this helped
J E CUSTOM

 

[Varmint Hunter]

I've been shooting the 7 STW for many years. My only concern was that quality brass was non-existent and I'm not interested in forming brass for this cartridge. Although, I must admit that I was able to get some very tight groups with fully preppped and sorted Rem brass.

Yesterday I noticed that Nosler is now making their "custom" brass in 7 STW. This could breath some new life in this old cartridge.

 

[ingotoutdoors]

I've owned rifles in both 7 stw and 7 ultra, and like them both very much. but i just finished a 7.21 lazzeroni firebird and I think i prefere it over both of these cartiges. its case and thoat are a hair shorter allowing the bullet to be seated in or closer to the lands wich allows me to fit them in the mag. for hunting use(don't have to use as a single shot), and a hornady 139 interbond at 3700 fps does some damage. i have found this to be extremely acccurate( 2"-2 1/2" @ 500 yards in a hunting wieght rifle!)and easy to load for. thats just my opinion, but i think i would choose the stw over the ultra if i had to, i think its less finiky

 

[Fiftydriver]

When talking about the "finickiness" of a specific chambering compared to another, its really hard to do this when comparing same bullet weights when your dealing with different case capacities.

I will only talk about the chamberings mentioned and asked about in this post.

If you take a 7mm STW, I like to see at least a 27" barrel to be used just to get a very high % of powder burn before the bullet exits the muzzle. With this case capacity, you have a relatively bullet friendly chambering for bullets from 140 to 175-180 grains. In my opinion, very best bullet weight is the 160 gr and I feel the Accubond is very hard to beat.

The STW with this bullet weight class is very user friendly, not finicky at all and generally very accurate in a well built rifle.

If you drop to 140 gr bullets, you will have to look a bit harder to get a proper powder to get REALLY consistant velocities. It can certainly be done but often not the first time out.

If you drop to 120 gr bullets, this becomes even more of an issue. MUCH harder to get tight velocity spreads and generally, the lighter you go in bullet weight in these big case, not only does the velocity advantage over smaller chamberings decrease but also, often times, consistancy and down range accuracy will be lesser then a heavier weight bullet.

A 160 gr bullet just seems to be a very good balance of weight for this capacity and bore size. Most often best accuracy will be in the 3100-3200 fps range with a 27" barrel length.

Heavier bullets work very well in the STW as well, even up to 200 gr but you start to see velocity really drop off with these very heavy bullet weights.

Now lets look at the 7mm RUM. Where the STW is a bit finicky with the 120 gr class bullets, the same can be said for the 7mm RUM with the 140 and even in some instances the 150 gr class bullets. Its just a large capacity chambering for this bore size.

As such, the heavier the bullet you put in this very large case, the more efficently the large dose of very slow burning powder will burn. Personally, even though the 7mm RUM was released with a 140 gr bullet, I feel its really a waste of time to shoot anything lighter then the 160 gr in the RUM class chamberings.

Do not read that as me saying that no bullet lighter then 160 gr will make a consistant accurate load in the 7mm RUM. That is not the case at all. What I am referring to is over a wide range of rifles in this chambering, you will often see accuracy and consistancy really start to improve once bullets of 160 gr and higher are used in the RUM class chambering.

The 160 gr pills are good, but the 175-180 gr bullets are even better for offering consistancy and accuracy at long range in this large case. Velocity spreads will often shrink noticably with the heavier bullets.

To the extreme, the 200 gr bullets really settle the big RUM down nicely. They do not produce the sexy velocities that the lighter bullets will but hitting the vitals at long range will be much easier with this bullet then with the lighter ones.

Anyway, point is, comparing one chambering to another when both are in the same bore size but noticably differnet case capacities, its hard to compare them head to head.

Best combo in the 7mm STW would be in my opinion, a 160 gr in the 3100 -3200 fps range.

Best combo in the 7mm RUM would be a 180 gr bullet in roughly the same velocity range.

Simply put, you have the same velocity range with either of the preferred loads but the 7mm RUM offers you a heavier, higher BC bullet which will outperform the STW at ranges pasts 1/2 mile.

If you compare both with 140 gr bullets, yes the RUM can be a finicky chambering. If you use the proper bullet weight in both chamberings, I have never seen either to be any more finicky then the other. Just hard to compare them head to head because for both, their best performing loads will be very different in personality.

Again, just to prevent another explosion, I am not saying the STW is not fully up to 1000 yard range or even farther with great effectiveness and accuracy, it certainly will. But there can be no denying that the RUM will drive a heavier, higher BC bullet to the same velocity and that adds up to shorter time of flight, flatter trajectory, less wind drift, higher retained velocity for better bullet terminal performance and higher retained energy which also adds to terminal bullet performance and tissue damage on target.

You just have to decide what your game is. In my opinion, there is no such thing as over kill. I also admit amazing things can be accomplished with pretty much any chambering if the bullet is put in the right spot.

Take your pic, match what you want to do with this rifle to the performance advantages of both chamberings.

If your shooting less then 700-800 yards, the advantages of the 7mm RUM will probably not be realized over the STW and the longer barrel life would be a considerable advantage. At longer ranges, you will be able to see the ballistic advantages of the larger chambering.

Remember though, velocity is like sex, they both sell. In reality, heavy, high BC bullets will far outperform any lightweight hyper velocity bullet at any range past 600-700 yards. Out past 1/2 mile, no comparision so I would much rather focus on which bullet to use, then consider the engine to drive that bullet to the velocity you want for your goals with the rifle.

Kirby Allen(50)

 

[ncpreacherboy1]

When talking about the "finickiness" of a specific chambering compared to another, its really hard to do this when comparing same bullet weights when your dealing with different case capacities.

I will only talk about the chamberings mentioned and asked about in this post.

If you take a 7mm STW, I like to see at least a 27" barrel to be used just to get a very high % of powder burn before the bullet exits the muzzle. With this case capacity, you have a relatively bullet friendly chambering for bullets from 140 to 175-180 grains. In my opinion, very best bullet weight is the 160 gr and I feel the Accubond is very hard to beat.

The STW with this bullet weight class is very user friendly, not finicky at all and generally very accurate in a well built rifle.

If you drop to 140 gr bullets, you will have to look a bit harder to get a proper powder to get REALLY consistant velocities. It can certainly be done but often not the first time out.

If you drop to 120 gr bullets, this becomes even more of an issue. MUCH harder to get tight velocity spreads and generally, the lighter you go in bullet weight in these big case, not only does the velocity advantage over smaller chamberings decrease but also, often times, consistancy and down range accuracy will be lesser then a heavier weight bullet.

A 160 gr bullet just seems to be a very good balance of weight for this capacity and bore size. Most often best accuracy will be in the 3100-3200 fps range with a 27" barrel length.

Heavier bullets work very well in the STW as well, even up to 200 gr but you start to see velocity really drop off with these very heavy bullet weights.

Now lets look at the 7mm RUM. Where the STW is a bit finicky with the 120 gr class bullets, the same can be said for the 7mm RUM with the 140 and even in some instances the 150 gr class bullets. Its just a large capacity chambering for this bore size.

As such, the heavier the bullet you put in this very large case, the more efficently the large dose of very slow burning powder will burn. Personally, even though the 7mm RUM was released with a 140 gr bullet, I feel its really a waste of time to shoot anything lighter then the 160 gr in the RUM class chamberings.

Do not read that as me saying that no bullet lighter then 160 gr will make a consistant accurate load in the 7mm RUM. That is not the case at all. What I am referring to is over a wide range of rifles in this chambering, you will often see accuracy and consistancy really start to improve once bullets of 160 gr and higher are used in the RUM class chambering.

The 160 gr pills are good, but the 175-180 gr bullets are even better for offering consistancy and accuracy at long range in this large case. Velocity spreads will often shrink noticably with the heavier bullets.

To the extreme, the 200 gr bullets really settle the big RUM down nicely. They do not produce the sexy velocities that the lighter bullets will but hitting the vitals at long range will be much easier with this bullet then with the lighter ones.

Anyway, point is, comparing one chambering to another when both are in the same bore size but noticably differnet case capacities, its hard to compare them head to head.

Best combo in the 7mm STW would be in my opinion, a 160 gr in the 3100 -3200 fps range.

Best combo in the 7mm RUM would be a 180 gr bullet in roughly the same velocity range.

Simply put, you have the same velocity range with either of the preferred loads but the 7mm RUM offers you a heavier, higher BC bullet which will outperform the STW at ranges pasts 1/2 mile.

If you compare both with 140 gr bullets, yes the RUM can be a finicky chambering. If you use the proper bullet weight in both chamberings, I have never seen either to be any more finicky then the other. Just hard to compare them head to head because for both, their best performing loads will be very different in personality.

Again, just to prevent another explosion, I am not saying the STW is not fully up to 1000 yard range or even farther with great effectiveness and accuracy, it certainly will. But there can be no denying that the RUM will drive a heavier, higher BC bullet to the same velocity and that adds up to shorter time of flight, flatter trajectory, less wind drift, higher retained velocity for better bullet terminal performance and higher retained energy which also adds to terminal bullet performance and tissue damage on target.

You just have to decide what your game is. In my opinion, there is no such thing as over kill. I also admit amazing things can be accomplished with pretty much any chambering if the bullet is put in the right spot.

Take your pic, match what you want to do with this rifle to the performance advantages of both chamberings.

If your shooting less then 700-800 yards, the advantages of the 7mm RUM will probably not be realized over the STW and the longer barrel life would be a considerable advantage. At longer ranges, you will be able to see the ballistic advantages of the larger chambering.

Remember though, velocity is like sex, they both sell. In reality, heavy, high BC bullets will far outperform any lightweight hyper velocity bullet at any range past 600-700 yards. Out past 1/2 mile, no comparision so I would much rather focus on which bullet to use, then consider the engine to drive that bullet to the velocity you want for your goals with the rifle.

Kirby Allen(50)

thanks kirby....that is exactly the kind of info I was looking for.

 

[Tyler Kemp]

How fast could the RUM throw a the 200 grainers? Would it be any advantage over the 180s at 3200 fps? I have also seen STW velocities this fast, and I have heard the brass for it holds up better, giving the same velocity as the RUM.

I have already contacted you about rifle choices, but I am simply stuck between 7mm RUM or STW. I don't feel I need a 338 for deer, but it would sure put the hammer down.

 

[topwater225]

STW or WSM

I don't want or mean to hi-jack this thread, but it has some really good info that pertains to my dilemma which is oh, so closely related……..

I also have a new build coming which I picked the 7STW. However, I am still wavering back and forth between the STW and the WSM. My reasoning eliminates the RUM from my choices, because IMO......relating to my purposes....the STW is over-bore, but the RUM is way over the top. I don't want the extra recoil, so I set the upper limit to the STW.

My intention is to use this rifle as my primary hunting rifle and also a lot of long range shooting (for fun, clubs, competition). I also do not intend to shoot any lighter bullet than 160gr. The 175 and 180 grain will be the "norm".

My dilemma also stems from the fact that I have had an STW and been around other STW's and they were NOT what I would consider "tack-drivers", but they were all factory rifles – my rifle being a Weatherby. I love the speed, but my instinct keeps telling me to go with the proven accuracy of the WSM. This would also eliminate the belt - Which is actually not a huge issue.

What da ya think?

 

[dakor]

7mm STW

Accuracy in an STW will not be an issue I have worked up different loads for 6 different rifles and they all have shot 1/2moa or less. As for speed you can expect 3100 to 3200 fps with 175gr and 180gr bullets and 3300 to 3400fps with 160gr type bullets. Right now I have a LSR with a 28inch Broughton 5c barrel and am shooting a berger 180 at 3125fps with and ES of 5 and a 175 SMK at 3205fps with an ES of 6. With the same 20 cases I fired them 6 times before I switched to new ones so both loads are pretty mild. I did shoot the berger at 3200 fps but it did not shoot as well 3/4moa the 3125fps load shoots between 1/4 and 1/2 moa depending on how I shoot that day.

Here is a 3 shot group at 100 yards with the 180 Berger.

Here are two groups at 300 yards off the bipod. The first group is on the bottom and the one up high in that group was the first shot with oil in the barrel. The second group is up higher because I put a click on the scope two shots are in the same hole and the third is about an inch away. I blame the conditions for that one. I would say a 30inch barrel in a STW would have no trouble at all shooting 180's 3200fps+. As for range 700 to 800 yards is just the tip of the Iceberg with the load I have at 3125fps with the 180 Berger at 7500ft at 1200 yards 1886fps with 1422ftlbs with 59inch of wind drift with a 10mph wind. At 1500 yards 1635fps and 1068ftlbs with 99inch's of wind drift in a 10mph wind. We all know that these numbers change day to day even with the best Ballistics calc but if you can put the bullet where it needs to go Elk sized game or smaller are going to have a very bad day at 1500 yards or less.

 

[topwater225]

Thanks Dakor....that is the confidence building that I am looking for.

I am having LSR build my STW as well, so I really shouldn't be questioning accuracy. I would love to see pictures of your rifle....Will you post some of your LSR or send them to my personal email?

[email protected]

Thanks!