collapse

Advertisement


Author Topic: Virgin brass vs. once fired  (Read 538 times)

Offline Crunchy

  • Political Topics
  • Trade Count: (+2)
  • Frontiersman
  • *****
  • Join Date: Apr 2007
  • Posts: 4499
  • Location: Puyallup
Virgin brass vs. once fired
« on: January 20, 2021, 01:33:12 PM »
So I developed a really good load while fire forming virgin brass.  It is shooting 1/4 Moa at 200.  Today I had reloaded 8 pieces, and shot the last 3 of virgin brass.

Virgin brass still holding 1/4 Moa.  Once fired reloads opened up to roughly 3/4 Moa. 

Virgin brass ES of 11 SD of 5.7
Reloads ES of 34 SD of 11.

Should I run another ladder over the chrono now that the case volume has changed from virgin to once fired?  Maybe the sweet spot powder charge has changed from virgin to once fired?  Just curious what might have opened up the load.

Offline birdshooter1189

  • Trade Count: (0)
  • Hunter
  • ***
  • Join Date: Nov 2013
  • Posts: 201
  • Location: Port Orchard
Re: Virgin brass vs. once fired
« Reply #1 on: January 20, 2021, 01:50:03 PM »
I have a hard time believing the case volume is changing enough to have any effect on velocity.

I would suspect it might have more to do with neck tension and the brass hardening or softening after being once fired.

Could also be your test batch size....perhaps the spread didn't show up in a 3 round string but it did show up in a 8 round string.

Other possibilities could be barrel heating up, or barrel getting dirty.

Offline Stein

  • Non-Hunting & Covid-19 Topics
  • Trade Count: (+4)
  • Old Salt
  • ******
  • Join Date: Sep 2013
  • Posts: 8533
  • Location: Arlington
Re: Virgin brass vs. once fired
« Reply #2 on: January 20, 2021, 02:17:13 PM »
I haven't experienced that, I would try it again to verify it's the once fired issue and not something else.

Did you full length or neck resize?

Offline callturner

  • Trade Count: (+1)
  • Scout
  • ****
  • Join Date: Jun 2020
  • Posts: 280
  • Location: nine mile falls Washington
    • n/a
  • Groups: nra
Re: Virgin brass vs. once fired
« Reply #3 on: January 20, 2021, 02:20:22 PM »
 :yeah: Did you anneal your brass? Was it annealed before? What brand is it? Lots of variable's.

Offline buckfvr

  • Washington For Wildlife
  • Trade Count: (+4)
  • Frontiersman
  • *****
  • Join Date: Jun 2010
  • Posts: 3558
  • Location: PREDATOR PIT UNIT 121
Re: Virgin brass vs. once fired
« Reply #4 on: January 20, 2021, 02:33:22 PM »
Did your average velocity remain the same ?  If not, match once fired velocity to virgin velocity.

Offline Buckjunkie

  • Trade Count: (+1)
  • Scout
  • ****
  • Join Date: Oct 2010
  • Posts: 407
  • Groups: USMC Vet, NRA Life Member, SCI Member, WAFNAWS Life Member
Re: Virgin brass vs. once fired
« Reply #5 on: January 20, 2021, 03:14:49 PM »
I have several rifles that like (good quality) new brass and the rest don’t seem to care.

For this rifle, I would either shoot all virgin, or start over working up a load with 1x + fired brass.

Offline Crunchy

  • Political Topics
  • Trade Count: (+2)
  • Frontiersman
  • *****
  • Join Date: Apr 2007
  • Posts: 4499
  • Location: Puyallup
Re: Virgin brass vs. once fired
« Reply #6 on: January 20, 2021, 04:16:10 PM »
Did your average velocity remain the same ?  If not, match once fired velocity to virgin velocity.

the reloads averaged 8fps faster than the virgin brass.  I would note that this round of shooting was about 50 fps slower than previous.  I assumed it might be because of the temp difference.  Guess I need to load another batch to figure out what is going on.  Everything is the same.

Offline Crunchy

  • Political Topics
  • Trade Count: (+2)
  • Frontiersman
  • *****
  • Join Date: Apr 2007
  • Posts: 4499
  • Location: Puyallup
Re: Virgin brass vs. once fired
« Reply #7 on: January 20, 2021, 04:17:27 PM »
:yeah: Did you anneal your brass? Was it annealed before? What brand is it? Lots of variable's.

It is ADG brass, came looking as if annealed. I anneal every other firing so I have not cycled enough brass to anneal yet.  Next firing I will.

Offline Crunchy

  • Political Topics
  • Trade Count: (+2)
  • Frontiersman
  • *****
  • Join Date: Apr 2007
  • Posts: 4499
  • Location: Puyallup
Re: Virgin brass vs. once fired
« Reply #8 on: January 20, 2021, 04:20:47 PM »
I haven't experienced that, I would try it again to verify it's the once fired issue and not something else.

Did you full length or neck resize?

I full length resize.  The groups are night and day from virgin to reloads.  The virgin brass might be less than 1/4 Moa it is shooting great at 200.  At 100, three shots are one hole.  the reloads are prob .75 Moa so I know it is not me.

Offline NWShooter

  • Political Topics
  • Trade Count: (0)
  • Hunter
  • ***
  • Join Date: Jan 2016
  • Posts: 205
  • Location: Oregon
  • Groups: RockyMountain Elk foundation, Mule Deer Foundation, NRA.
Re: Virgin brass vs. once fired
« Reply #9 on: January 20, 2021, 08:37:43 PM »
Fairly simple. Shoot “Virgin” brass. Next would be to work on the shoulder bump as per the chamber dimension.
A empty vessel makes the most noise.

"Every normal man must be tempted , at times, to spit on his hands, hoist the black flag, and begin slitting throats."

Offline Magnum_Willys

  • Political Topics
  • Trade Count: (+1)
  • Frontiersman
  • *****
  • Join Date: Nov 2009
  • Posts: 4531
Re: Virgin brass vs. once fired
« Reply #10 on: January 20, 2021, 08:48:35 PM »
Yup can be frustrating.  Have a 338-378 that with virgin brass I just have to fill with powder,  stuff bullet in and shoots 1/2 moa out to 1000 yards.  Difficult to match with resized brass tho tried many ladders, loads, tensions and annealing every time.  Took 3 different dies before I found one and a load that matches virgin accuracy.   Its a hunting rifle so I just use virgin brass.

Offline bugs n bones

  • Trade Count: (+1)
  • Longhunter
  • *****
  • Join Date: Aug 2011
  • Posts: 900
  • Location: north bend
  • Groups: WSTA, NRA, SCI
Re: Virgin brass vs. once fired
« Reply #11 on: January 20, 2021, 09:00:05 PM »
Long story short... if your brass is fire formed in your weapons chamber , you then neck size only second go around . 99.9 % time that always has a better group .

Offline Crunchy

  • Political Topics
  • Trade Count: (+2)
  • Frontiersman
  • *****
  • Join Date: Apr 2007
  • Posts: 4499
  • Location: Puyallup
Re: Virgin brass vs. once fired
« Reply #12 on: January 20, 2021, 09:03:18 PM »
Fairly simple. Shoot “Virgin” brass. Next would be to work on the shoulder bump as per the chamber dimension.

I am only bumping the shoulders back 2 thou.

Offline Crunchy

  • Political Topics
  • Trade Count: (+2)
  • Frontiersman
  • *****
  • Join Date: Apr 2007
  • Posts: 4499
  • Location: Puyallup
Re: Virgin brass vs. once fired
« Reply #13 on: January 20, 2021, 09:06:14 PM »
Yup can be frustrating.  Have a 338-378 that with virgin brass I just have to fill with powder,  stuff bullet in and shoots 1/2 moa out to 1000 yards.  Difficult to match with resized brass tho tried many ladders, loads, tensions and annealing every time.  Took 3 different dies before I found one and a load that matches virgin accuracy.   Its a hunting rifle so I just use virgin brass.

I loaded up another ladder.  The load in virgin brass is 67.6 grains of H1000. So I am starting at 67 and going to 68.5 in .3 steps.  Hope to find the "magic" again.

 


* Advertisement

* Recent Topics

Razor clams by GWP
[Today at 11:39:05 PM]


WTB 12g 2 3/4 Turkey Shells by northwesthunter84
[Today at 11:38:02 PM]


FS/WTT: Various Ammo by solomtnhunter
[Today at 10:49:02 PM]


Auction.....(COMPLETED) by silverdalesauer
[Today at 10:33:03 PM]


WTS Kuiu down hooded jacket by cem3434
[Today at 10:05:44 PM]


I am ready for bear season by SpicyTacos
[Today at 09:59:44 PM]


Youth turkey gun recommendations? by buglebuster
[Today at 09:42:01 PM]


Trade/Co-op reloading stuff by JJB11B
[Today at 09:29:58 PM]


Any leads on remington 700 supercell recoil pad? by TooTallMike
[Today at 09:14:45 PM]


6.5 swift siroccos by Parkern
[Today at 09:11:07 PM]


Sitka Cloud burst set by Parkern
[Today at 09:09:25 PM]


WTS/WTT: Factory .243Win, .17 Hornet, and 1 Case CCI 450 Primers by swordtine
[Today at 08:59:57 PM]


WTS: Sitka Gear Cloudburst Jacket and Pants by TMC
[Today at 08:32:56 PM]


Saddle Hunting - Who knew by zwickeyman
[Today at 08:31:55 PM]


PUP WON'T STOP CHASING CHICKENS by actionshooter
[Today at 08:31:13 PM]


HS Precision Remington 700 BDL Short Action Stock by TMC
[Today at 08:30:01 PM]


Wenatchee Area Buddies by phildobaggins
[Today at 08:28:47 PM]


Turkey Regions by Birdguy
[Today at 08:25:54 PM]


Cleaning out the office with stuff I am not using. by Farmer72
[Today at 08:22:21 PM]


WTS: kifaru Smith Stove 18" by Karl Blanchard
[Today at 08:22:15 PM]