If you can be more specific you can be with the goal of the rifle, it will help ensure you get the best advice here. What size and type of targets, if used in competitive shooting, what discipline, your reloading experience, off the shelf ammo availability wants, barrel life expectancy desires, shooting string length and intensity, would be some of the requirements you should definine for yourself. Maybe you can list those after some thought.Looking at the 7mm Remington Magnum for 1000yds+ I know its a barrel burner, not looking at long strings of continuous fire, just wanting to know if its capable.
The goal of the rifle is to get to the 1 mile mark, reasoning for the 7mm RM is my late father had one in a Weatherby Vanguard VGS and it was his elk gun, and I've taken several whitetail with the same rifle. Just kind of have a soft spot for the cartridge itself. Mainly plate steel targets 24"x24" at 1000+ just to prove to myself that I can do it, I've been reloading for around 5 years and keep gaining better equipment to chase accuracy and precision, scales/dies/measurement tools ect... not looking to shoot more that 5 consecutive shots in a string and I understand that even doing that the barrel life may only be around 800 rndsIf you can be more specific you can be with the goal of the rifle, it will help ensure you get the best advice here. What size and type of targets, if used in competitive shooting, what discipline, your reloading experience, off the shelf ammo availability wants, barrel life expectancy desires, shooting string length and intensity, would be some of the requirements you should definine for yourself. Maybe you can list those after some thought.
The 7RM is a very capable chambering.
I've got a Tikka T3X CTR in .260 Rem that I could take to a mile if need be. I just wasnt for sure if the 7mm RM would get there with more velocity and energy and less wind deflection. The starting point is to get to a mile, as well as past when I accomplish my personal mile challenge.You can get a short action cartridge such as a 6.5 creedmoor to a mile if that's your only criteria...
A 6.5 shooting a 140 grain projectile at ~2800 fps can shoot out to ~1900 yards at sea level very reliably and predictably. I've found past 1,900 yards, it starts to fall apart (at sea level).
If you want something more wind resistant, and with longer range capabilities, the .300NM is becoming a very popular mid-range ELR cartridge.
The 7RM certainly would - though admittedly I don't know much about the cartridge.I've got a Tikka T3X CTR in .260 Rem that I could take to a mile if need be. I just wasnt for sure if the 7mm RM would get there with more velocity and energy and less wind deflection. The starting point is to get to a mile, as well as past when I accomplish my personal mile challenge.
I was tossing around the idea of 300WM or 300NM, I know that both of those cartridges have alot more recoil than the 7mmRMThe 7RM certainly would - though admittedly I don't know much about the cartridge.
If you want a real barrel burning 7mm for ELR, you may want to check out the 7XR - it's a 300NM necked down to a 7mm. You can send 180 grain pills about ~3500 fps. But you will have to change barrels every 500 rounds.
My vote is still .300NM.
The .300NM is very easy to shoot, out a good brake on it and it doesn't recoil hard at all. The recoil of a .300NM is a slower impulse, it's not as punishing as you may think.I was tossing around the idea of 300WM or 300NM, I know that both of those cartridges have alot more recoil than the 7mmRM
I've never bought 300WM or 7mmRM brass. So I can't compare, though undoubtedly the .300NM brass will be more expensive.Hows the brass price on the 300 NM compared to 300WM and 7mmRM?
I did some digging real quick on the 7LRM, only place to get brass is GunWorx, and not super crazy about that. I'd like to stick with something more main stream that I can get a stock pile of components for, and basic load data out of a book, thanks for the info tho!The 7RM is a good cartridge, but suffers from American idiocy.
Your typical flannel shirt wearing American outdoorsman figured that since H&H had belts on their magnums, all magnums must have belts and wouldn't buy one without.
So that left us with a couple of good cartridges, that could have been great cartridges if they didn't have that retarded fucking belt.
Since you reload, look at the 7LRM. It is a long action magnum cartridge without the a belt. It is based on the .375 Ruger, has the same .532 boltface as a standard magnum but increases the powder capacity by approx 5-6 grains.
It is not as much of a barrel burner as the .28 nosler and the 180 ELD-X will get you where you want to go.
You'll find plenty of experienced handloaders that don't consider belted magnums to be bad. Other are down on the shorter brass life. Some use custom dies to try to extend life and improve precision.Also: can anyone tell me why the belt on the belted magnum cartridges are a bad thing? I'm ignorant on that subject
they serve absolutely no purpose. They can also interfere with feeding.Also: can anyone tell me why the belt on the belted magnum cartridges are a bad thing? I'm ignorant on that subject
So how would I set the die to headspace off the shoulder?Yeah, use the die. The belt was used to headspace those old cartridges like the Holland Magnums because they looked like the old rimmed Nitro rounds (in form) so needed something better than long, sloping shoulders to headspace on but couldn't use rims like the double-rifles since rimmed cartridges don't free really well from mag fed bolt guns like the square bridge Magnum Mauser rifles. Modern belted magnum rifles still headspace off the belt but you can use your die to effectively headspace off the shoulder for better consistency.
Steel is the only thing on the menu for this one, and what exactly does this reamer do? As far as bringing the 7mmRM into the 21st century?The 7RM will outrun the SAUM by a bit. You'll need a WSM based 7 to run ckose to the 7RM. The belt is a non issue for precision. The 300 WM or NM will be easier to spot impacts for at a mile than the 7RM. Travis Reddel with RBros Rifles has a 7RM finisher reamer that takes an old case and brings it into the modern times.
How heavy of a rifle do want this build to be? Are you ever going to hunt anything but steel with it?
Same as any other bottle neck cartridge. Shoot it until its tight in the chamber, then bump the shoulder .001. Belts suck. I hate dealing with them, but its the price I pay to shoot 300WM. I use the LW die.So how would I set the die to headspace off the shoulder?
You or any number of competent gunsmiths could spec out the reamer the same, was just giving you a known data point/easy button for a smith that has the 7RM nugged out. You will want to headspace off the belt for the first firing, and then off the shoulder for subsequent firings. The 7RM doesn't have a long neck, so getting the FB right to accommodate the class of bullets you're wanting to shoot takes some math/homework ahead of time. There are some guys I think that struggle with the 7RM because the chamber needs to be set up to allow the case needs to "breathe" on that first firing, in order to allow the reloader to headspace of the shoulder for subsequent firings. He's one guy that has that figured out, and is a great smith to boot.Steel is the only thing on the menu for this one, and what exactly does this reamer do? As far as bringing the 7mmRM into the 21st century?
I hate belted cartridges because the belt is irrelevant.People hate belted cartridges for the same reason they were once popular. Ignorance. The belt is actually irrelevant. Ignore it. It helps nothing. It hurts nothing.
But, what do I know? Only been loading belted cartridges for 50 years and likely that many barrels.
They have no feeding issues, no pressure issues. Set up to headspace off the shoulder and shoot...
You sir answered my question exactly! What a wealth of information!! Thank you so much!Ideally, a chamber setup for precision rifle shooting a belted cartridge will have a finish reamer with increased length on the dimension from bolt face to the shoulder datum. The belt headspace dimension will be SAAMI/CIP.
This will allow you to chamber and fire out of the box SAAMI/CIP spec brass. This first virgin firing will be headspaced off the belt.
It normally takes approx 4 full pressure firings for a case to fully confirm to the chamber. For examples sake, let's say you used a nk sizing only die during these first 4 firings. The case shoulder would be slowly stretched forward (there's the "magic" in this specd finish reamer dimension so as to not overly stress the case but enable it to be headspaced off the shoulder in subsequent firings) so as to meet and confirm to the chamber shoulder wall.
Eventually the case body and shoulder would provide a near interference fit to the chamber during extraction, and while neck sizing would allow you to seat a bullet, you'd encounter difficulty closing the bolt on your newly loaded round. So you'd need to squeeze the case body diameter, and reduce the bolt face to shoulder datum case length with a FL sizing die so you could chamber a newly round. You would set up your FL sizing die JUST LIKE A NON BELTED DIE, to bump the shoulder .0015-.003 from the 4x fired dimension.
Wa La. Belted mag, that's headspaced off the shoulder.
You should FL size from the very first firing, as the brass case develops a "memory", and if you nk size only until it's tough to chamber/extract, you may encounter sticky extraction with that brass for it's life even after FL sizing, as it's now springing back to it's "new" oversized nk sized only for 4x firing state.
Another note, there are collets available to size the "bulge" that can form just north of the belt. But a chamber that's setup correctly will avoid this issue all together and it won't be needed provided you FL size from the first firing, and the FL sizing die/chamber case body diameter are on the same page.
Just as was posted above, belted mags set records in previous times. There certainly have been innovations in precision, but there's no reason a belted mag cant shoot with competitive precision in any discipline against it's non belted competition.
You don't see belted mags used in benchrest simply because the 6PPC and 6BR based chamberings blow everything else away and are subsequent overwhelming favorites in those disciplines that compromise exterior ballistic performance for pure precision.
You don't see belted mags in FClass because shot string length and firing string intensity. The 7 SAUM/WSMs are borderline in those disciplines, in terms of barrel life, throat abrasion, and subsequent bullet deformation issues some encounter.
For the shorter strings of fire your talking about you'll be in good shape with a 7RM. Barrel life will depend on the lot of steel your barrel was made from, cleaning method/frequency, velocity/pressure level of ammo, and how intense/long your shooting strings are.
So basically about $1 of barrel life per shot then.I have a large amount of data regarding barrel life and large capacity 7mm belted cases. Compiled over several decades of worldwide hunting.
7 Rem, 7 Weatherby, 7 STW, 7/300 Win mag, 275 H&H, 7/375 H&H. All pushed to max safe velocity with 160 grain bullets.
Barrel life was from 650-900 rds with no long strings of fire. Mostly CM barrels not stainless. Most of the barrels went from superb to keyholing in less than 20 rds. rather than fading away.
I usually get a couple loadings using the lee collet die before I bump shoulders, and determine if I have to use the LW die. I imagine this will be my last 300WM barrel. I want similar performance without the belt because the belt is only sort of irrelevant. The way the chamber is cut and the relation to the belt, as you say, is what causes the problems, the need for the die, and another step in the process. Reloading takes long enough without it.Every belted mag chamber is slightly different and so is every size die, meaning if you won the lottery in tolerances you might not need to use the LW belt die, or at least not for x number of reloads, before the brass needs to tossed. If you lost that lottery in tolerance stack, then plan on using the LW die every time or every other time. This also depends on the strength of the brass.
Using the LW belt dies an extra step in the reloading process, that's extra time I like to avoid.
Personally if I had a belted mag again I'd buy virgin brass and shoot it once, then sell and replace with virgin again.
Of course the easy button is not having a belted mag. I seriously doubt I'll own one ever again and I've had three 7mmRM's.
In 7 cal I would opt for 7 Saum. Right now in 30 cal I'd opt for 300N, but that 300PRC is coming out soon which I would choose over it simply for the extra barrel life and powder savings. Anymore these days I'll sacrifice the extra 100 fps the hotter cartridges provide for the sedate because that extra 100 fps means so little from a ballistic viewpoint.
It's kind of funny to me that I've had my 30-375R wildcat all these years and almost changed cartridges a few times but never committed. Turns out it's such a capable and well balanced cartridge that I have no reason to change. The only way I see any benefit is going up to something like a 338L AI or a 375 something and that means a lot of $$$$. If I were serious about ELR I'd go for one of these bigger cartridges but I'm not.[/QUOT
These were all in different rifles, two of them factory hunting rifles and many years ago, back then I had no choice but to throw the brass away when they wouldn't fit anymore.@steve123
Do you have a copy of the reamer print used in your 3 7RMs? And maybe a pic or the following stats from your gun data book on those rifles?
4x fired bolt face to shoulder datum dimension
FL sized bolt face to shoulder datum dimension
4x fired body dia .050 north of the belt
FL Sized body dia .050 north of the belt
Did you measure and analyze these dimensions before throwing away your once fired 7RM belted brass?