Problem with belt cartridge

[Kevin Thomas]

Mada,

Don't skip the resizing step, even if you "can" in some cases. Ideally, you want your ammo (especially hunting ammo) to chamber just like the factory stuff does; smoothly with virtually no pronounced resistance. Neck sizing will eventually give you problems unless you really (REALLY!) watch your measurments closely, each and every time you process the cases. I recommend full length sizing as a general rule, with very few exceptions. Life's just easier that way.

Boomtube's perfectly correct here, also, in that some cases can be neck sized by backing off a F/L die, but most cannot. Depends on the configuration of the case, but as a rule, backing off a F/L die actually results in what's correctly known as "partial sizing." To my mind, that's a bit of a non-solution, and brings its own problems to the mix. Full length size using a full length die, and neck size (if you must) using a proper neck size die made for the task.

 

[snowpro440]

I have one of these dies. It works. Innovative Technologies - Reloading Equipment

+1 for the larry willis collet die , this will take care of your problem with reloading belted cases, just dont over lube your case necks....

 

[Mada]

Mada,

No, neck sizing is a different issue, and it cannot be doen (in most cases) by simply backing off a FL die. You need a true Neck Sizing die if you're going to do this, one that touches only the neck and is not touching the body. Personally, I reccomend against it, particularly for hinting ammunition. You'll eventually have chambering issues with this, and it will usually manage to come at a very inopportune time.

Try the lube solution first, but stick to the FL sizing. I usually recommend a chamber type gage, such as the Wilsons, or a bump gage like the Hornady or Sinclair, just to make sure you're getting adequate clearance where needed, and no more.

Wouldnt it be wise to chamber the cartridge after neck sizing, if I do, to avoid the problems of not being able to chamber the cartridge in the field?

 

[Mada]

+1 for the larry willis collet die , this will take care of your problem with reloading belted cases, just dont over lube your case necks....

I've read on these collets, but they are expensive.. especially for my pocket. I would buy them if I found no other way around it. 89 bucks D: I'd rather neck size since I have just one rifle for each load

 

[jimbires]

I've never seen the need for the collet die . I load 7 rem mag , 300 wby . I just use regular dies and never had a problem . what problem were you getting that the collet die corrected ? thanks Jim

 

[snowpro440]

derrick , You are using other peoples brass in your gun so there chamber is not the same as yours. So you want to size the base of the case just above the rim with larry willis die because standard dies will not resize all the way down like the larry willis die. Also after you fire them in your gun and resize them several times they may expand at the base of the case just from the pressure and you will have the die to fix your problem... its your choice to buy new brass or buy the die. I shoot my new brass 6-8 times and borrow a friends die to fix mine, then I am good to go for a few more reloads. good luck, I hope this helps.

 

[jimbires]

I've never seen the need for the collet die . I load 7 rem mag , 300 wby . I just use regular dies and never had a problem . what problem were you getting that the collet die corrected ? thanks Jim

derrick , You are using other peoples brass in your gun so there chamber is not the same as yours. So you want to size the base of the case just above the rim with larry willis die because standard dies will not resize all the way down like the larry willis die. Also after you fire them in your gun and resize them several times they may expand at the base of the case just from the pressure and you will have the die to fix your problem... its your choice to buy new brass or buy the die. I shoot my new brass 6-8 times and borrow a friends die to fix mine, then I am good to go for a few more reloads. good luck, I hope this helps.

I only have used brass from my gun . I know I have brass with 7+ fires on them without problems . I guess I'm just lucky . thanks Jim

 

[Mada]

The brass I am using is only from my rifle.

And, Jim, do you ever have a problem with resizing your brass? It seems im .005" fatter above the belt and it wont fit all the way into my die. They've told me to get Imperial case resizing wax to help with resizing :x

 

[jimbires]

The brass I am using is only from my rifle.

And, Jim, do you ever have a problem with resizing your brass? It seems im .005" fatter above the belt and it wont fit all the way into my die. They've told me to get Imperial case resizing wax to help with resizing :x

I've never had a problem resizing my brass . I use the RCBS lube ,( oil )on a lube pad . I lube then I just push the brass in to the sizing die when it gets tight I back out a little , and then go in more . it might take 3 , 4 , 5 , ?? tries until I get it completely in . I've never measured my brass above the belt , I've had no reason too . the imperial case wax is very slick stuff , it should reduce friction . I have some 7 rem mag brass here that was fired from another rifle . just for the heck of it , I'll resize a couple to see if they will fit my rifle . Jim

 

[woods]

Mada

Some chambers are larger than others. The factories buy reamers that are as large as possible but still within SAAMI standards so that they can use them the maximum number of times before they get too small and wear out (at least that's what I've been told). The bulge above the case head is common and is where the solid case head ends and the open case body begins

The only rifle I have that has a demonstrable bulge is my Steyr 30-06

the bulge is not exclusive to belted cases and the belt really has no bearing on whether it will have a bulge or not.

Lube is the answer. Your press and dies were MADE to solve this problem. There are several rifles out of the 40+ I reload for that have cases that are harder to resize than others. One in particular is a Remington 300 win mag of a friend which is a major effort and crunch time when it comes time to resize. Also have one rifle where the chamber is so small that the resizing die will not resize the case body at all even when fully inserted. There are a lot of variable in the chamber size and interior of die dimensions that will determine how much effort resizing takes. Lube it and do it! Nuff said!

You will have to lube the hell out of the case before you could get it into a die with the Innovative Collet also, so that will not change things.

 

[kc0pph]

I have a friend with the 7mm and he had the same issue, the bulge looked like a small elongated bubble. I was worried about case head seperation if I loaded them for him. So we did a red nek check on his chamber. We sprayed the chamber with oil (i think it was the spray rem oil) Put a dowel in the barrel and packed the chamber with clay. Then we let it dry, pushed it out with the dowel and saw that there was a part that looked bulged. He sent it back to Remington and im assuming they replaced the barrel. Might try doing this and see if you have an issue with it. I hear that sometimes if it is reamed fast and without care, and backed out while spinning a chip can get caught and roll in the reamer and cause it to chip the chamber.

As far as Neck Sizing using a FL die i have never had success with it. Took a 30'06, blackened it with my trusty lighter (outside as i have powder spilled and in the carpet ). I raised the ram, then screwed in the die until it touched the case. Removed and saw it started to neck down the 06 to the 270, (using my RockChucker it takes some force to neck down the 06). Using slow adjustments by the time i got it to set the shoulder back the blackened case had been wiped away all the way down.

I am using RCBS FL dies.

Another lesson i learned the hard way. The expander ball needs to enter the case BEFORE you size the neck, or else you might not be able to get it in. I crushed the Neck trying to force it in.

 

[jimbires]

I know this is not much of a fact , it is a sample of one . I used a RCBS precision mic , and a blade mic to measure with .on the brass from the other rifle I pushed the shoulder back .0125 , and never swelled the case . Jim

brass fired from my rifle .
DIA. before ................... after
.5088 .............................5088
.5084..............................5088
.5087..............................5081

shoulder length before ............. after
-.003.....................................-.003
-.0035...................................-.003
-.003.....................................-.003


brass from other rifle
DIA. before ..........................after
.5077...................................5075
.5075...................................5076
.5079...................................5077

shoulder length before ..................after
+.0105........................................-.002
+.0105........................................-.002
+.0105........................................-.002

 

[Bart B]

Belted cases have had accuracy problems since their inception near 100 years ago. But It wasn't until around 1960 that a few top competitive shooters figured out what their problem was. Until then, new belted cases typically shot the most accurate in the long range matches.

Problem is, the case body immediately in front of the belt expanded enough between the front of the belt and the chamber's headspace ridge causing a step in the case body at that point. Conventional full length sizing dies don't size a fired belted case body all the way to the belt so that ridge, or step, is there after using such a die. And, of course, no neck only die didn't either.

When a conventionally sized belted case gets chambered, that ridge will interfere with the chamber at that point causing the back end of the case to be positioned a tiny bit different for each shot. It depends on how high that secondary step is and where on the case circumference its high point is (case wall thickness playes a part here; cases aren't uniform in wall thickness at this point). When the round fires, forces at that point cause the barrel to whip differently for each shot as the bullet goes down the barrel. 'Tain't much difference between shots, but enough to open a 600 yard 3" group up to 5 or 6 inches. If that step's pretty bug, accuracy can degrade further.

So, one needs to get rid of that step. 50 some years ago, folks would take a standard full length sizing die, cut it off about 1/4th inch up from the belt clearance edge and about 1/4th inch below the body-shoulder junction. After squaring off the bottom end, it would be set up in the press such that a case already full length sized die (with its neck lapped out to 3 thousandths smaller than a loaded round's neck diameter so no expander ball's used) could be sized again in this "body" die such that that step was reduced back down to the same diameter as the body immediately in front of the belt. In other words, the belted case has its body diameters sized down to virtual new case dimensions.

Now there's no step on the case to cause accuracy problems. Accuracy's as good as it gets. Larry Willis' collet die now does the same thing with that step. But it may be cheaper to make a "body" die from an existing full length sizing die.

 

[Mada]

Sorry, Bart, but I dont get what you're trying to say