9.3x62 dreaded brass doughnut ring

Why not? said:
Brass doughnut rings will develop through firings in chambers with excessive headspace, and subsequent full length resizing.

Set FL Resizing dies to size fired brass to have a slight crush fit. You will not have doughnut rings when doing so.

Ted
Click to expand...
ted,
are you talking to just neck size down to the shoulder , and not bump the shoulder
 
Creat positive headspace on the initial firing by creating a false shoulder. Try that with 3 cases, resize and see what that does.

You will need a 375 mandrel or expander ball to start the process.
 
From "Modern Loading" second Edition, Richard Lee suggests 0.002" neck tension for most cases - so a 9.3 mm bullet measures about 0.366" diameter - so you probably want about 0.364" inside neck diameter to seat a 0.366" bullet, without need for a crimp. 23/64" is .359375" - too small. 24/64" (3/8") is 0.375" - too big.
 
Probably what I would try - take fired case - drill out neck with 3/8" bit - then re-size - die should crush neck too small, then expander button should open that neck to correct diameter - unless that button not all the way down in case body when resizing?? Same idea might work with 23/64" bit - is all based that the die's expander ball is resizing the whole length of the neck, after the FL die has crunched that neck too small diameter.
 
  • Like
Reactions: DGY
For trying to find "hang-up" on brass - I used Jiffy Marker and coloured the case - showed me where the "contact" was occurring - in my case that was a "ring" just ahead of the belt on some Weatherby brass that the FL sizing die would not re-size - I had to buy a specialized die that only sized that area - not the whole case - the die cost much less than the 300 x Weatherby cases that I ran through it.

As far as having the cases tried in other guy's rifle - back in the day, a friend had same cartridge as I did - 308 Win - both of us could use factory ammo from same box and both of us could use the other guy's reloads. However, his fired brass would NOT fit into my chamber to allow my bolt to close, even though mine would fit into his rifle and he could close his bolt. Chambers are not cut precisely the same - even though "nominally" the same cartridge - apparently .00001" and .000001" matter
 
  • Like
Reactions: DGY
If it happens with one type of brass, and not another, it is a good indication that it is a brass issue (in your chamber); Out of curiosity, weight a good piece of brass, and then one of the ones you have an issue with. I would be surprised that the ones with the ring that are causing you issues are not slightly heavier (more brass). In which case ream the neck to size after sizing the brass, this will get rid of the extra metal.
 
bcsteve said:
The last thing touching the inside of your neck is the expander ball expanding the neck out. How can a raised ring still be there?
Click to expand...
That was my thought as well. If his scenario is correct , his cases shouldn't chamber even before a bullet is seated.
edited to add...If the expander ball is doing its job then the brass should be ironed out when the ball is extracted and require outside reaming not inside.
 
Last edited:
dutch_m said:
brand new brass loaded up , shoots excellent , loads and feeds great bolt closes nice

once i resize it , loaded up 5 rounds and couldn't get the bolt handle to go down, double check to see if still 100 tho off the lands , it was all good ,
then i thought must have super tight chamber , checked again and all good , then i thought i must not be pushing the shoulder back enough , so i resized with a full down to be 100% sure on them being full lenght sized ,

so i was at a loss , couldn't figure it out after reloading for 35 years, called a buddy who has the same 9.3x62 and on the phone , couldnt figure what it was , so i mailed him 10 rounds that i shot and resized , and 2 that were shot and sized ounce and loaded,

when he got them , same thing, they wouldn't load in his rifle , so this made me think i had a bad die , i was using a Hornady and he had a RCBS die , so he went and sized one again and loaded it and the same thing happened again ,with his die , would not close the bolt , now both of us stumped

it came down to just eliminating one step at a time , it had to be the brass , brand new norma brass , 100 bulk i got , when loaded the first time , no troubles at all , feeds and bolt opens and feeds and closes and feeds , empty case pulls out easy , something was happening to the brass and only after firing and only after a full length size , after some light down in the brass we noticed a small small round ring at the base of the neck , we took a drill bit and removed the ring of brass , then loaded the round and it feed perfect , this was the cause of the trouble

after fired and a full length size , the brass got a ring inside down at base of neck , which when a round was seated it was just enough to push the brass out to be super tight in the chamber , on research its called a dough or doughnut ring ,

So now the fix ,

i tried a few with a nice drill bit , not really liking how they looking on the inside of the necks , some stuff i found on the internet is reamers , just cant find one for the 9.3x62 , next was a way of doing a trim on the insides of the necks , some benchrest shooters do this

anyone else have this happen and any opinions on best way to fix this Norma brass , remove that little round ring of brass in the case neck
Click to expand...
Forster makes inside neck reamers for this exact purpose. I’m sure other brands make them too.
 
You must log in or register to reply here.
Back
Top Bottom