Neck sizing and shooting

[swampratt]

I got some measurements of this R-P case I will test out.
I did pick this up as 1 time fired with primer still in it.
I annealed and brushed it and Full length sized it then turned the neck to make it uniform.
If you notice it is not clean cut all the way around the neck as I took off as little as I could.
.0015" or a tick less.

 

[retrieverman]

8 lbs of it.
Have not thought about it.
I do love IMR4064 and N133, H4895 come in close to my like list

I’ve got some IMR4064 and H4895 I could probably be convinced to part with.

 

[Jcann]

I load 50 rounds at a time and only neck size. Once I see accuracy decline do I full length resize and anneal. I think a quality barrel is a must before any testing is conducted. Any reload we creat is only as good as the barrel it is shot through. I know many have created reloads that shoot through factory barrels with great accuracy but there is nothing like shooting through a custom barrel. I can get sub moa out of bullet weights from 162-180 gr in my Bartlien barrel with very little effort. And, I dont Have to worry about do I need to neck size only or full length resize to do it.

 

[retrieverman]

As I said previously, I full length size all my brass and always have. What’s the advantage of just neck sizing?

 

[Jcann]

First off brass that is once shot is fired formed to the chamber. Naturally it springs back some but will chamber again and again to the same rifle. Resizing the neck only doesn’t work harden the brass near as much as full length resizing.

The neck is the only part of the brass that comes in contact with the bullet and that’s the part I want to control. I have a die that only sets the headspace one to two thousandths back. It doesn’t touch the case body or the neck. I use this die always along with the neck resizing die. The neck resizing die is a bushing die whereby I control how much resizing to the neck is being done.

I try to limit how much work hardening I expose my brass to and resetting headspace and neck resizing does that for me. Naturally, over time I do need to full length resize.

I turn all my necks to 15 thousands neck thickness and knowing my neck chamber dimension I can properly set my bushing. I control bullet seating pressure, neck tension, and runout this way. If everything is done properly I get consistency shot to shot. And that’s what we are looking for in hand loading.

 

[retrieverman]

That’s very interesting, and I appreciate the explanation.

 

[magna19]

I got some measurements of this R-P case I will test out.
I did pick this up as 1 time fired with primer still in it.
I annealed and brushed it and Full length sized it then turned the neck to make it uniform.
If you notice it is not clean cut all the way around the neck as I took off as little as I could.
.0015" or a tick less.

How do you know its only been fired once?

 

[swampratt]

How do you know its only been fired once?

Guy at the Banner Road range was shooting store bought ammo and could not get good groups and going hunting to Colorado.
He kept adjusting his scope chasing the bullet holes.
I told him it was not his scope and let him shoot 3 of my Lapua cases loaded with one of my accuracy loads for my 2 .308 rifles.
He shot a clover leaf group.
I gave him 4 more rounds to take hunting and he gave me the almost boxes of store ammo.
There 4 rounds left of that ammo that was not fired.

Now onto some numbers.
I went yesterday to Lexington WMA.

First shot was FLS case then next 2 shots neck sized at the range.
.730" center to center and the 3rd shot went right of the first 2.

168 Tipped Match King 41.5gr AA2495.
The 3rd shot came out with a sooty neck.
4th shot went 1.37" away from the 3rd shot but went Left.

I annealed the case. and It had a bit stiffer seating force for the bullet.
5th shot went Left and Higher.

Cool down time.
6th shot went under the first 2.

Over all case length grew .005"

Picture.

 

[swampratt]

Next up was Varget 42.6 gr powder and 168A-Max.
First shot up was annealed before firing and I pulled a dry bore snake through the barrel 2 times.
First 3 shots were .560" center to center.

4th shot I pulled due to a bug buzzed my ear just as the trigger was about to break.
I quickly built a 5th round and it went high.

Cool down time so I shot my .243.

Case neck was sooty but a consistent sooty so I did not anneal any more.

Case grew in length .006" this time and is now 2.018" AOL
Primer pockets were cleaned each time and my CCI 200 primers feel just the same when seating.
Nice and firm seating pressure.



Next up was the hunt load I use as it has been great all the time I shoot it.
No more annealing and I did not clean the barrel any.

155 A-Max 44.4 gr IMR 4064 CCI 200
.914" center to center group No fliers.

 

[swampratt]

Something I noticed a couple weeks ago when I was shooting was chamber temp.
I placed a round in my chamber and lined up on target and was about to let it fly and my target fell over.

I cycled the bolt and removed the round so i could go down range and stand my target back up.
I was shooting by myself on private land with NO one around and do not know why I removed the round.

The round was pretty warm in my hand.

The barrel was not that hot but I guess the chamber was.

This got me to thinking.
This round was in the chamber long enough to get on target and almost let it fly and then removed.

Case fill on my Varget loads with the 168A max is not very full and well below the bottom of the neck.
Case fill on my 155 load with 4064 powder is almost right at the base of the neck.

Could it be the heating of the case in the chamber makes my last 2 shots with the Varget go to fliers.
Every time I go out shooting that 42.6 gr load or less I can stick 3 touching or really close to each other and then the last 2
always blow the group.

Yes I could allow 10 minutes cool down between shots.

I will continue this test but I will up the Varget charge a bit and see what happens.

Loads discussed here are safe in my rifle consult a loading manual for loads for your rifle.

Last Note: Case length is now 2.023" another .005" of growth.

17 times fired so far.