220 swift Win Brass has me stumped?

[deadlyswift]

Well guys, I have ran into something that I have never encountered before.

A friend and I went groundhog hunting a cpl of weeks ago. Decided that current brass had to many firings. So loaded up some vrgin brass for the hunt. This vrgin brass is 10 to 12 years old. I read somewhere that old brass can harden with just age. Not knowing for sure I annealed the necks. Just to feel better about it.

We are planning on hunting again this weekend. I pulled the once fired brass to start prepping it for the next hunt. In the past with this rifle and all my rifles I have always been able to slide a bullet in an out of the neck with ezz or the bullet just drops right into the case (Before Resizing). Not the case this time? With the 50gr. Blitz King I can only just get the taper of the boatail into the neck by hand? My seater die will seat the bullet. What I can't figure out is why the neck isn't expanding any upon firing? This is a Ruger M77 target with factory barrel. I haven't had this problem before in the past with this rifle, so why now? Only thing I can figure is exsessive neck wall thickness? Not sure on how to fix this other than just getting some new brass, or trying to ream the inside of the neck to thin the brass up? New brass might fix the problem, but me just being me I'd like to figure out what is going on here? I figure a new problem spells knew knowledge. Does any one have a explanation for this? What do I need to do to fix the problem with this brass? More less why are the necks not expanding?
Thanks!
Mark

 

[tunered]

Measure the outside neck of them cases and then compare numbers with other cases fired in the same chamber, that should tell you if the necks are to thick. ed

 

[bozo699]

Mark,
Sounds like your neck wall thickness is thick,as I recall depending on manufacturer .013-.015 usually .014 ,I would check some of your old brass and compare to this new brass.DON"T turn the inside of your neck turn the outside down if needed,bump it back out with a mandrel then resize,you will have change neck bushing as needed,then good luck on the groundhogs.

 

[drouinhomebuilders]

Mark,
I have some WW 220 swift brass thats about 4yrs old, the nick thickness prior to turning was 18 thousands.
I have looked for more with similar thickness, but the best that Ive found of late
has been around 14.
I myself like the thick walled stuff, In my experience it is very uniform

 

[4xforfun]

Measuring fired cases tells you nothing about neck thickess. Load 1 or 2 bullets in the new, seemingly thick casses and load 2 more in your old "normal" brass. Measure the loaded rounds and compair. The only other way to accuratly measure neck wall thickness is with a ball micrometer and do some math. Yes, you can also measure neck thickness fairly well with a really good pair of callipers, but not as precise as the ball mic.

If the new stuff is thicker, so what. As long as it chambers there is nothing wrong with it. I would keep it seperate from your other brass, and, if it were me, I would get a chamber cast made and measure your actual neck diamiter to see how much room you have to spare. I can't imagin you would be anywhere near max neck diameter on a factory bbl, but, you never know. Just watch for PSI signs on what should normaly be safe loads.

Also, compare the neck diameter of a loaded round to the fired case and see if the fired case neck has expanded at all.

If, by chance, you are nearing the danger zone, and the brass is indeed
to thick" , do not throw it. Either try and get the necks outside turned by a friend, learn to do it yourself, or sell it. There is nothing wrong with it.

Hope this helps.