Belted Cases Are A Pain

[Engineering101]

I've done my own loads for over 50 years but I've never until recently owned a rifle with a belted case. I also hadn't loaded for one until a couple of years back when I helped a hunting buddy tune his 7mm Rem Mag and in the process noticed the bolt was pretty hard to close some times. Another friend when talking about his 7mm Rem Mag indicated that he could barely close the bolt even with factory ammo due to the headspace being a "little tight". Recently I bought an old Sako Finnbear 7mm Rem Mag to use as a donor action for a 26 Nosler build. I floated the barrel, tuned the trigger, installed a new Limbsaver at my preferred pull length and then I loaded some ammo to see if the platform was good to go even though I knew I was going to pull the barrel. It shot good but some of that ammo fit pretty tight. I then helped a friend tune his 338 Win Mag. He had some once fired brass and after reloading (full length resized) it was a struggle to close the bolt on about half of it. The other half were OK but not as easy as a full lenth resized non-belted case which basically takes zero effort to chamber.

All of this has made me glad I don't own any rifles that use belted cases (now that the barrel has been pulled off the Sako 7mm Rem Mag). I don't hear much mention of this issue but do hear how much guys like their 7mm Rem Mags, 300 Win Mags etc. If you look at the design of belted cases and the way they headspace it seems like they don't have much forgiveness, nevertheless I figure I must be doing something wrong. So what do you do to produce ammo that fits easily in the chamber every time?

 

[MudRunner2005]

I've never had any issues with ANY of my belted mags, and I've been shooting them most of my life... Sounds like some crappy brass, or a badly cut chamber or the factory did a bad job headspacing the barrels... None of my rifles have ever had any of those issues, except for when I had some old Federal STW brass that got overworked and wouldn't spring-back to size after firing...Then the bolt gave me issues, but after chunking that brass and buying some new brass, I haven't had anymore issues like that.

What could be the cause of that could be a fat chamber....Oversized in girth by an out-of-spec reamer, or a barrel that wasn't properly zero'd in the lathe when the chamber was cut. It will make your brass expand more, and become fatter than normal, and it won't spring-back as much and you'll have issues getting the bolt open and closed. So, you might wanna take a couple of once-fired brass and measure the girth near the belt to see how much out of spec it has expanded to. Then you will have your answer as to if it's a brass issue, or a chamber issue.

My money would be chamber issue.

 

[Engineering101]

Mud

That is pretty amazing. Every rifle I've come across with a belt has had this issue. I was of course blaming the rifle/brass for the first couple of times but if the problem keeps happening you got to start looking at what you are doing. If I get what you are saying, I'm not doing anything wrong but have just had a string of bad luck. I am still working with the friends 338 Win Mag and we decided to get new Nosler brass so I will be giving that a try soon. Sounds like it will work fine.

 

[Engineering101]

Mud

Is it true to say that with your rifles when closing the bolt on ammo that you have loaded you can't tell the difference between a rifle with a belted case and one without?

 

[Truc]

the issue I have seen with belted cases is when the load is on the upper end and the case swells just in front of the belt. The dies can't size it, I believe someone came up with a die that solves this issue but can't think at the moment who makes it

 

[Pdvdh]

I don't have any problems with the belted cartridges. 7mm RM, 300 Win Mag, 338 Win Mag, 338-378 Wthby Mag, 375 Wthby Mag. 375 H&H Mag.

The belted case - in an of itself - isn't the problem. Measure where you're getting the interference, figure out what's causing it, and then correct it. Blacken the case exterior with a black felt pen, chamber the round (or attempt to chamber the round), and examine for the location of the interference/contact.

 

[Timber338]

Mud
Is it true to say that with your rifles when closing the bolt on ammo that you have loaded you can't tell the difference between a rifle with a belted case and one without?

This is my experience with all of my belted mag rifles.

I've reloaded 7mm, 300 and 338 win mag for dozens of different rifles over the past 20+ years. The only time I've run into real problems of having the bolt close hard is when I tried the whole "neck size only" game. I stopped doing that a very long time ago and would only FL resize brass, and then never had any problems.

What I do now is use Redding Competition Shellholders that allow you to bump the shoulder back .001 to .002 inches smaller than the chamber. This effectively eliminates headspacing off of the belt. If I were to run across any brass that is hard to chamber, I would just throw it away. But right now using Nosler brass I have not had a single issue through several different batches of brass for both 300 win mag and 338 win mag.

You can achieve a similar result to bumping the shoulder of any brass by just adjusting your die up and down, but not only is this a very tedious process, it has also been proven through finite element modeling to produce larger variations of shoulder bump from case to case that ultimately come about from having a gap between the shellholder and the bottom of the die.

So anyways, I would assume that if a belted mag case is FL resized and the bolt still closes hard when chambering the ammo, that there is a problem like what Mud describes, or it could just be a batch of brass with poor control over the location of the belt. And Truc is right that you can get swelling in front of the belt but I personally have only had that happen on reloads that were way over max pressure. I'll be curious to hear how the Nosler 338 wm brass works in your buddies rifle. Hopefully that alone fixes any problems you guys were having.

 

[Halleywood]

the issue I have seen with belted cases is when the load is on the upper end and the case swells just in front of the belt. The dies can't size it, I believe someone came up with a die that solves this issue but can't think at the moment who makes it

Innovative Technologies makes a collet resizing die for belted rounds. I ordered one as I was getting tough to chamber rounds on brass that had been shot numerous times. This sizes the area just above the belt that a regular FL sizing die doesn't get. It worked well for me.

 

[Deleted member 46119]

Every design, belted and not, has problems (duh).

As this thread demonstrates, it is a hot debate subject. I'm not fond of belted designs.

Many people here have more experience with belted case designs than I do.
but
It seems to me that if you have a chamber that is within spec there are no problems.

If your chamber is not in spec then the experienced guys have work arounds and extra tools to overcome the problems that just don't exist in non-belted cases.

The two things I have encountered are long chambers and wide chambers.

Long chambers wreak havoc on the brass by allowing it to stretch at the belt body junction. I have seem more case head separation on belted designs than any others.

Bulging just in front of the belt or including the belt itself. Since the resize dies do not compress the belt or the belt body junction, your stuck. If you lower the die to resize this area then you are over working the brass in this area and inducing case head separation. There is a collet tool that fixes this but it is another tool...

With a couple exceptions every belted design rifle I have was or will be rechambered or rebarreled.

So far I've worked with:

• 270 Wby two rifles, both rifles within spec. In fact, they had the same fireformed dimentions. One was rebarreled anyway.
• 300 Wby three rifles, 2 within spec. one with a fired case length that was .020 longer than the others, that one was used as a donor. A custom on a Hall repeater action will be rechambered to RUM. The 'factory' one is fine but allows the belt to grow a little. Not requiring a 'fix' though.
• 338 WM, No problems with this one but its getting rechambered to 338/26 Nosler

Depending on how the world goes I may be able to get some 257 Wby loads made and test fired to see how the chamber is on that one.

 

[MudRunner2005]

Mud

Is it true to say that with your rifles when closing the bolt on ammo that you have loaded you can't tell the difference between a rifle with a belted case and one without?

When everything is setup 100% correctly, yes, you should not be able to tell the difference.

Like has been mentioned, my experience with switching every belted caliber I own to Nosler brass has also been good.

 

[Elkhunter1983]

I bought the IT die and love it. The top has a case guage in the top and will make belted mag brass last longer. Some of my many fired cases were having trouble chambering as well.

 

[Cold Trigger Finger]

I've had and reloaded for around 30 belted rifles. Belts are my preferred method of headspacing, but I love the 375 HandH and the 458 Win Mag. When I started loading for the 338 RUM, 308, 375 Ruger , 9.3×64 Brenneke , 300 Short RUM and the 6.5 Creedmoor it took some doing to learn about thenot having a belt to solve the headspace issue. But it didn't take too much. I figured it out. I love belts on my cartridges but practicality dictated that I had to learn to deal with beltless .
At one point 2 friends and I all had and hunted with 7 Rem Mags the fired brass from 1 of them wouldn't chamber in the 2 others but that is one of the few times I've had that problem.
All my Ruger M77 mk2 ss 338 Win Mag rifles. 9 of them were the slickest feeding rifles I've ever owned and the only time they chambered tight was because the brass needed trimming.

 

[Engineering101]

I appreciate all the comments and info. It is good to know that there should be no difference between a properly setup rifle that uses belted ammo and one that does not. I also noted the comment that full length resizing a belted case does not do anything to the belt. Good too know.

As I indicated I had no experience loading belted ammo until recently. With every one of the rifles I mentioned closing the bolt was an iffy experience. Since none of them are my rilfes I just kept going as the bolt would close with a little extra effort but nothing crazy. The 338 Win mag will be the first time I will have used what I consider to be very good brass (Nosler) in a belted case and I expect this issue will go away for that rifle.

 

[Cold Trigger Finger]

Something sounds fishy. You should see some of the brass that I've reloaded and shot. Litterly trusted my life with. Cruddy crusty crap that has been tarnished a lot from salt spray. Frozen iced up. Sawdust and hemlock needles sticking to it . As long as the chamber isn't too tight and I've full length sized it it flew into the chamber and went bang with full velocity.
The stakes were high. But the distance was short. I would also keep it trimmed up a little short so I had some crud room if needed.

One thing that will give a problem closing the bolt is over compression of powder. Like putting 72 gr of IMR 7828 in a 338 Win Mag case and seating a 300 gr Barnes Original to 3.40 oal then crimping into the cannalure I rolled in with a CH4D cannalure cutter. Or 76 gr of IMR 4320 into a 416 Taylor case and cramming a 325 gr X bullet onto of it to 3.4" oal. . Sometimes the sides of the case would bulge out and I couldn't close the bolt.
Long cases and bulged case bodies are the only 2 causes I ever had with rounds that wouldn't chamber.
But that was with fighting ammo not LR ammo and I ALWAYS crimp fightin ammo.
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