Carbon ring on belted mag

[LVJ76]

Thanks Shooter, scored a leftover tag at 36C, we'll see how it goes, but it will be warm though.

Good luck and stay safe

 

[LVJ76]

OP is saying same issue with new Unfired cases.

OP maybe I missed it, do you clean with bronze brushes? Interested in the outcome on this one. Wish you had a scope

I am using both, bronze and nylon but mostly a nylon 20ga that's rather hard and scrubs really good. I've never had to deal with a carbon ring so if there are better ways I'm open to suggestions

Thanks again

 

[MZmoose]

If there was a carbon ring building up near the belt the fired cases should come out sooty near the belt. Never heard of or seen carbon build up there.

 

[jarnold37]

I don't believe your problem is a carbon ring. What is happening is your case is enlarging just in front of the belt . This happens from time to time in belted mags when you have a die that does not match up good with your chamber. If you would happen to have a 300 Win /300 Weatherby/ STW sizing die on hand you could try screwing it down tight against your shell holder and running your 7mm Rem case all the way up in the die. This may get that area sized if not then you may require a Larry Willis die. JMO

Innovative Technologies - Reloading Equipment

Our patented resizing die can reload Winchester, Remington and Weatherby belted magnums up to 20 times, instead of just 2 or 3 times and the top of the die is a chamber width gauge.

www.larrywillis.com

Maybe not your problem, but measure the size of your chamber just ahead of the belt. Using a pin guage will show how much bigger diameter the back of the chamber is compared to diameter of an unfired case. I have several rifles with belted cartridges and have chambered many barrels in belted mag cartridges. If the chamber is big at the mouth or back, then it is a chambering issue (bad chamber). It is harder to resize a belted case in such a chamber because the belt becomes big also. I have cracked two expensive dies trying to size swelled case and belt. If there were dies available I would turn the belts off in the lathe. Belted cartridges are ok but make sure of the chamber.

 

[LVJ76]

If there was a carbon ring building up near the belt the fired cases should come out sooty near the belt. Never heard of or seen carbon build up there.

Maybe not your problem, but measure the size of your chamber just ahead of the belt. Using a pin guage will show how much bigger diameter the back of the chamber is compared to diameter of an unfired case. I have several rifles with belted cartridges and have chambered many barrels in belted mag cartridges. If the chamber is big at the mouth or back, then it is a chambering issue (bad chamber). It is harder to resize a belted case in such a chamber because the belt becomes big also. I have cracked two expensive dies trying to size swelled case and belt. If there were dies available I would turn the belts off in the lathe. Belted cartridges are ok but make sure of the chamber.

Thanks guys. I'm thinking if not a carbon ring maybe just a dirty chamber. Not a chamber issue because the barrel already has 300+ rounds down the barrel and this issue is new, it started say 20 rounds ago or less.

I'm gonna do a couple more overnight wet patches and see qhat happens. After that I'll try full sizing the brass and go from there. Also getting a bore scope.

Just been curios if anyone with a belted mag has had this issue before.

Thamk again everyone and stay safe. I'll keep you posted.

 

[PddPdd]

I believe I had the same problem with 300 Win Mag cases after a few firings. It was solved by using the Larry Willis die to resize the brass more completely near the belt.

Possibly related experience: I have a 28 Nosler that shot fine for over a 100 shots with handloads but when I put some store bought Hornady rounds in it, it would not extract the brass after firing. Turns out there was a small burr in the shoulder of the chamber that was scratching and holding onto the brass. A gunsmith removed the burr to solve the issue.

 

[MagnumManiac]

Your issue is not caused by a carbon ring.
If I read your first post correctly, I believe you are neck sizing your brass?
Do away with neck sizing, partial FL sizing and lubing the INSIDE of your necks will eliminate 99% of the issues.
If the issue is bulging just ahead of the belt, then there is 2 ways to eliminate it:
1) Buy a body only sizing die and use that to size your brass, BUT if it doesn't size the bulge, then;
2) Buy the Larry Willis collet die.
I have several belted mags, as a result, I can size the bottom of my cases, if needed by running them into a longer belted case die without touching anything other than the base.
I have not had to do this though.

Cheers.

 

[LVJ76]

I believe I had the same problem with 300 Win Mag cases after a few firings. It was solved by using the Larry Willis die to resize the brass more completely near the belt.

Possibly related experience: I have a 28 Nosler that shot fine for over a 100 shots with handloads but when I put some store bought Hornady rounds in it, it would not extract the brass after firing. Turns out there was a small burr in the shoulder of the chamber that was scratching and holding onto the brass. A gunsmith removed the burr to solve the issue.

Your issue is not caused by a carbon ring.
If I read your first post correctly, I believe you are neck sizing your brass?
Do away with neck sizing, partial FL sizing and lubing the INSIDE of your necks will eliminate 99% of the issues.
If the issue is bulging just ahead of the belt, then there is 2 ways to eliminate it:
1) Buy a body only sizing die and use that to size your brass, BUT if it doesn't size the bulge, then;
2) Buy the Larry Willis collet die.
I have several belted mags, as a result, I can size the bottom of my cases, if needed by running them into a longer belted case die without touching anything other than the base.
I have not had to do this though.

Cheers.

Getting one of the Larry Willis dies is a good idea but first I want to try cleaning the chamber again because the factory ammo also gets stuck and it did not before.

I did a count of new factory ammo fired through this rifle and I have fired 212 rounds, and after counting the bullets I have loaded on it it has just over 200 reloaded rounds fired through it.

Of those 212 factory rounds about 10 of them have gotten stuck and from 2 different brands that were not an issue before, and these in the last 2 trips to the range so its a new issue.

Thats what tells me its not a sizing issue, at least not yet.

 

[PddPdd]

I would take some diameter measurements above the belt to see if there are differences between the cases that will and won't chamber.

 

[LVJ76]

I would take some diameter measurements above the belt to see if there are differences between the cases that will and won't chamber.

Gor it, thanks

 

[MagnumManiac]

The carbon ring you are describing is virtually impossible unless you are loading very low pressure loads and the case is not sealing the chamber correctly.
It is more likely a dirty barrel and throat causing an issue.
Anyway, factory ammo isn't always undersize on the belt, have seen plenty of factory ammo with belts too large, cut eccentrically and uneven from one side to the other. This causes sticking in the chamber where the belt headspaces off.

Cheers.

 

[Sleds]

Any update on this?

 

[LVJ76]

Not yet, was out hunting this last weekend.

Should have an update by next week.

Thanks

 

[LVJ76]

Alright so there is no carbon ring now for sure, I did some thorough cleaning of the chamber, and I mean thorough and there is nothing there anymore, thanks @Bravo 4 for lending me the borescope.

So now I'm going to load a couple rounds that will be full size lenght instead of neck and try them out.

I will be trying these full size rounds, also some factory and then some loaded neck size rounds and we'll see what happens.

Thanks again everyone and I'll keep you posted, should have some results by next week.

Stay safe all