What am I doing wrong?

[shoots for fun]

My problem deals with inconsitancies with neck tension. I am loading for a 204 Ruger. I started with new W/W cases. I first run them through a Hornady New Dimension Die to FL resize them. I then used RCBS TrimPro and their neck turning adapter. I turned them to clean up what I thought was about 75% of the neck. I checked dimensions, with a ball micrometer and found that they were pretty consistant, .0115. I then began working up and firing test loads. Bullet run out was .002 to .003 on most with a few set aside for "warm me ups" ;D

With the brass once fired I used a Forster neck die and a .223 bushing for the second loading. I checked several cases during this and they all were pretty consistant to the .223 bushing, perhaps at the most a .001 difference. However when I went to seat the bullets, 7 of the 40 cases allowed the bullet to drop in with very little finger pressure. ???

Did I turn to much? Is it the equipment I'm using? Could it be the spring in the brass? Or do I need to go to a .222 bushing. My case necks loaded measure .225 as I was trying for a .002 neck tension. The test loading provided a good 5 shot group with Hornady 32 gr VMax over 26 gr of Re10X @ 50 yds.

Thanks for any input you can give, and I have a thick head so let me have it!

 

[HolyMeekrob]

I would first go back and check your numbers. By my calculations they don't add up. You state that your neck thickness is .0115. With a .204 bullet diameter this equates to .227, and a .223 bushing would give you .003 neck tension. However you also say your loaded rounds measure .225 which equates to a .0105 neck thickness and a .223 bushing would give .001 tension.

The neck tensions I mention are assuming brass spring back. My bushings appear to already be adjusted for spring back. But let's say that the case is that your loaded rounds are .225 and you run them through a .223 bushing you'll generally get a spring back of .001 giving an exterior diameter of .224. If you're getting .001 variance then it's possible you have a few outliers that actually sprang back to an exterior diameter of .225. Obviously this gives a neck tension of .000

 

[RonAKA]

I agree something does not add up with the numbers. Do you have a micrometer that measures to the 10th of a thou? Depending on your bullet, it may be under 0.204". Typically Forster bushings are marked as to their actual size. That would mean the case should come out about 0.224" due to spring back. If your loaded rounds are 0.225 then that is 0.001" tension which should not let bullets fall through.

I suspect you may have more variation than you think in your neck brass thickness. Also measure some sized brass to see what the OD of the neck is before bullet seating. That should give you some idea if the Forster bushing is really 0.223".

But, at the end of the day, your bushing is too large for the brass you have if bullets fall out. The only question you should answer is 0.222 small enough.

 

[sailhertoo]

The numbers don't ever add up in my case. I buy 10 bushings @ $20 a peice and only use 3 of them. Thank God Sinclare does refunds! I hope!

 

[fullersson]

If your bullets can be seated with finger pressure you need to go down to the next size bushing. Your numbers don't sound right to me, but it doesn't really matter if your neck tension is that loose drop down to the next size bushing. Good luck.

 

[shoots for fun]

Thanks for the input. Your right about the numbers not adding up. I did some follow up measuring this morning with my RCBS Case Master and prepped 20 new cases to verify. I used Forster .2045 expander after FL resizing and before turning. Neck thickness came out @ .0105 to .0110. I then run them through a .223 bushing. Finished cases showed a consistent neck diameter of .224 and a loaded round of .225+ with no bullets dropping through.
When weather and time permit, I'll fire these and run them back through the bushing to see what happens. Though this particular gun is a single shot H&R handi-rifle I think I will use the .222 bushing instead. I'm loading about .015 from the rifling which this gun and load seems to like, bullet sticking won't be a problem. Just one more thing, should I back off the turning depth?
Thanks again

 

[HolyMeekrob]

You said you're turning until 75% of the neck is cleaned up? If you're going to turn necks I think that's probably the minimum you should do. If you're worried about the necks being too thin I've turned my .223 as thin as .010 fired it through a factory .255 chamber and had no splits. If you go thinner you'll get more uniform necks which can't hurt, but your necks will also wear out faster.
I've also heard that uniform neck thickness can't even be seen on target until you get out toward 600 yards, so depending on the range at which you're shooting, it might even be a waste of your time to turn.