Brass Not Sizing Properly

[forrest-hunter]

I'm reloading 300 win mag using Lee dies - most of the loaded shells feed like butter but about 10% are locking the bolt or won't chamber completely- the brass has been loaded before with no problems - the loaded bullets do fit fine in my Wilson go-no go die - rifle is weatherby vanguard

[ReloaderFred]

You can color the cases with a black Sharpie and chamber them. The black ink will rub off where the case is coming into contact with the chamber and tell you where the problem is. Once you determine the problem, then you can start working on a solution.

Hope this helps.

Fred

[Rcmaveric]

Had that problem with my .270 Win cases most the case chambered fine but every now and then i wouldn't beable to close the bolt or the bolt was hard to close. I screw the resizing die till it contacts the shell holder. Upon resizing i noticed on the full stroke i wasn't touching the shell plate on the stroke of the handle. I started screwing the resizing die in a half turn after it contacts the shell holder. Now on sizing the shell holder contacts the bottom of the die and i haven't had any problems since.

[country gent]

Sizing belted mag cases can be tricky at times. The case is meant to headspace on the belt but sizing for this moves the shoulder back to far drastically shortening case life. A lot size to just bump the shoulder back .001-.002 from fired dimensions. But on a tight cut chamber the head of the case might not be sized quite enough to easily chamber. Inking a problem case with a magic marker will show what you have ( where its tight) and then the proper fix can be determined. There are custom special dies that size the case correctly for longest life. I believe you can still send redding 3 fired cases and have a die made for the rifle. There are others that do this also I think warner ( the maker of the highly accurate rear apeture sight) also offers this service.

I'm betting after a couple firings your case heads just ahead of the belt are expanded enough to be tight and may be in need of sizing a trick here is to use a bigger longer die witht the same body ( Maybe 375 H&H ) to size only the body then size the neck and bump the shoulder back as needed.

[EDG]

If you find case drag or interference on the base in front of the belt it may take another die to control.

The problem with using a longer die is the design of dies for belted rounds. Dies for belted rounds stop the shell holder against the die bottom before the top of the belt reaches the shoulder of the belt recess. When you set the die to accurately bump the shoulder back .001 to .002 the belt stops even further from the belt recess shoulder.

You could modify a .458 Win die to size the area in front of the belt.

Or you can cut off an extra belted magnum FL sizer body to get rid of the shoulder of the die. Then you would need to grind .010 to .020 off the bottom of the die to permit the belt to be driven up to the belt recess shoulder. This will resize all the case wall ahead of the belt.

Larry Willis also makes a collet die that can size the area ahead of the belt. It is expensive but will size most belted rounds.

http://www.larrywillis.com

215984

[1browski]

http://www.larrywillis.com

215984[/QUOTE]
This is a tool I will probably be getting soon for 3 in 7mm RM and a 300 WM. I have had some issue before on one of the 7mm with the bulge above the belt. I didnt use a marker but could see the rub marks on some. Looks like a good tool. I also use some Lee collet dies for neck sizing.

[forrest-hunter]

Used a small base RCBS resizing die - seemed to solve the problem - all casing chamber properly - have also ordered the Larry Willis collet die -I normally buy once fired brass - have 7 mag, 300 mag, and 338 mag.- this die should solve most of my problems