What 7 to build ?

[Mt.Boy]

Any suggestions on a good brake . Side port or radial ?

 

[weatherbee]

7-300 Weatherby. It outperforms the 28 and the 7mm STW. I wouldn't even think twice.

Ballistic coeficient plus speed = killing power and down range capabilities.

 

[MudRunner2005]

7-300 Weatherby. It outperforms the 28 and the 7mm STW. I wouldn't even think twice.

Ballistic coeficient plus speed = killing power and down range capabilities.

How will it outperform? Same bullets = same ballistic coefficient + similar velocities, will equal same killing power down range.

 

[highdrum]

7-300wby will not outrun a 28 nosler or 7 stw, they all have same case capacity? If you put ridiculous freebore to it ala normal wby mag chambers, you might get a bit more speed, but what's the point in that?

 

[FEENIX]

Is is a Rum action so it should work right?

I must have missed it, why not 7MM RUM and call it good?

 

[FEENIX]

Any suggestions on a good brake . Side port or radial ?

Side port, there excellent choices to choose from. If you want to make it Mntana made check out Kirby Allen's painkiller.

Speaking of Kirby, here's his take on 7MM STW vs 7MM RUM (https://www.longrangehunting.com/threads/7mm-stw-vs-7mm-rum.28209/) ...

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)

Hopefully, it will help you in your decision making. Good luck!

 

[weatherbee]

7-300wby will not outrun a 28 nosler or 7 stw, they all have same case capacity? If you put ridiculous freebore to it ala normal wby mag chambers, you might get a bit more speed, but what's the point in that?

The 7-300 will outperform both. I own all three, reload for all three. The Weatherby has about 5 more grains of case capacity room, that's quite a bit. The 7-300 gets anywhere from 75-100 FPS better on most loads.

 

[Methow Packer]

I have a RUM action and initially went with a 28 Nos, it's a bad --- round but I shoot alot and wanted to go less overbore so I re-barreled to 7-300 WSM.

I neck up Winchester 270 WSM brass and shoot, I'm getting 3000 FPS with 180's in a 26" barrel throated to 3.115" OAL.

I've owned a custom 7RM, and the 7-300 WSM is by far the easiest to load for, and is much more accurate in my experience. I just shot a 2" group at 840 yards with it.

If you don't want to wildcat I would suggest 7 WSM or 28 Nos, since you're building a custom don't get hung up on super available 7 rm brass..
ADG is making WSM brass in the future and 28 Nos will be out next month
Do it right and ditch the Retarded belted cases...

Here's my last 840 yard group with the 7-300 WSM

View attachment 115514

I totally agree. The WSM cartridge is amazing no matter what caliber you choose

 

[FEENIX]

I totally agree. The WSM cartridge is amazing no matter what caliber you choose

I don't doubt that, I own a .300 WSM and shoot 215s with it, but I'd hate to use a RUM action for one of the fatties ... but that's just me.

 

[highdrum]

The 7-300 will outperform both. I own all three, reload for all three. The Weatherby has about 5 more grains of case capacity room, that's quite a bit. The 7-300 gets anywhere from 75-100 FPS better on most loads.

300 wby holds 100gr from all sources I can see, the 28 holds almost 100.7 topped of to the very top. A 28, throated to 3.75 coal will push a 195 @ 3150+ with RL33. I don't see a wby getting 3250. Now Iif your comparing a standard saami chamber 28 with 3.4 coal length, yeah I get it. Need to go apples to apples for bullet placement in neck. Maybe if you share your velocities it'd be more enlightening.

 

[FEENIX]

300 wby holds 100gr from all sources I can see, the 28 holds almost 100.7 topped of to the very top. A 28, throated to 3.75 coal will push a 195 @ 3150+ with RL33. I don't see a wby getting 3250. Now Iif your comparing a standard saami chamber 28 with 3.4 coal length, yeah I get it. Need to go apples to apples for bullet placement in neck. Maybe if you share your velocities it'd be more enlightening.

I too am having a hard time with the comparative analysis. I understand that he owns and loads for all three but like you said, it would be more enlightening with the right info i.e., ...

7-300 WBTY: barrel length, twist, load (bullet type and weigh)/velocity, etc ...
7 MM STW: barrel length, twist, load (bullet type and weigh)/velocity, etc ...
28 Nosler: barrel length, twist, load (bullet type and weigh)/velocity, etc ...

Cheers!

 

[VLD Pilot]

It depends on a few things? But a old time 7MM RM is hard to beat!
Speed comes with a price the more powder you burn through a .284 hole
the more throat you remove. Plus there are all kinds of good 7RM components
available at a more reasonable price. Factory ammo is easy to find.
And it will work for about anything you want to shoot.

Agreed. The good old 7 RM is a great 7mm option for most big game. Today I think running the 284 in a bolt gun gives about the same performance as factory 7 mag ammo. Using much less powder with much less recoil. Today I rarely bring out my 7mag with a couple 284s in the safe.

 

[Will Mathieson]

Don't get caught up with the marketing of expensive cartridges. All the hype is to sell you about the same performance for more $$. The 7mm Rem Mag is an all round cartridge with long range capabilities. 180gr bullets are no problem for it. You can buy loaded ammo about anywhere and that is good if you misplace your ammo on a hunting trip. The animal you get will not feel the 100+ fps difference between a 7mm Rem Mag and anything else. With good shot placement the old .22 cal kills about anything.

 

[6.506ai]

I have owned a SAUM, WSM, a couple Rem Mags, a couple 7-300s, 28Nosler, 280AI. If I were going to do another 7 I would do a 7-270wsm, a 7SS, or a 7 Blaser Mag.

I have a 280ai running 180s at 2900