Is there something to be had from using all the same head stamp cases

[John4me05]

I am still a rookie loader and have been digesting all the info you guys have put up but im curious about something.. I noticed a few threads down a guy checking internal volumes of 308 once fired cases from Midway... Now i use all kinds of brass in my 223. Rp,Win,LC, and some odd balls i picked up.. I want pinpoint accuracy for long range hunting... Am i missing out on accuracy because of using different headstamps.. Is it increasing the pressure on 1 and decreasing it on another??

Sorry if this is a dumb Q

 

[W.E.G.]

Different cases have different internal volume, and different structural integrity.

Best to keep them sorted at least by headstamp, better yet by lot number within a particular headstamp.

Also keep track of number of firings for a particular batch of brass. Brass will show signs of fatigue. When you start to notice fatigue signs in several cases within a batch, you should discard the entire batch.

 

[nedg67]

If you are reloading for hunting, you have other things to worry about like Wind, how you are going to steady your rifle or the old thrill of the kill BLOOD LUST.

A mild WIND over 200M can move your bullet of target 1ft or more, i feel with hunting if you can achive a 4inch group at 100M in a sitting or crouched position without a rest your doing excellent.

if you are a target shooter like benchrest, geting brass all from same batch is a must, but two cases with same head stamp each from a difrent batch can be and are often very difrent.

i do some target shootin as well as hunting and i like to know when the bullet miss it was my fault not the guns.

You dont have to mesure the volume of evry case to achive a excellent level of accuracy, just basic preperation and learn to do things in batches.

I like to buy bulk brass from same batch, about 300 or more units.
Uniform the primer pocket and flash holes
Maybe debure the necks so projectiles seat in without scraping,thats it
I always store my bullets in 50 or 100 unit box's this is a once of job.
Use and reload your rounds eavenly so all the cases are fired the sam number of times.

That should give you many years of life from your cases...

For better accuracy, somthing you should look into is working up a load for your firearm !

 

[nedg67]

For better accuracy, somthing you should look into is working up a load for your firearm !

Difrent projectiles will de-stabelise at difrent velocities, depending on barel length inchs, rifle twists, new or worn etc.

In Australia we mainly use ADI propellant.
but 308's for example, with a Sierra 150gn HPBT the load chart indicates you can use:
Min Max
----------------------------
AR2219 37.0 40.0
AR2206 43.0 45.5
AR2208 44.0 47.0

you should realy try more then one burn rate in powder but i always try the powder i use most commanly that i buy in bulk first, in this case AR2208
I just finished working up a load for my 308 i loaded 7 lots of 5 rounds with powder charges of 44, 44.5, 45, 45.5, 46, 46.5 and 47 grains i kept these together by load.

and now the easy fun part:
The rifle should already be zeroed and adjusted for windage at 100M
Place a large target up with 8 clear points to aim at like 8 small targets
you will fire 7x 5 shot groups each 5 shot group will be at difrent target
you must aim at exactly same point for each group.

Bench your firearm with a front and rear rest.
fire any 3 or more rounds to warm and foul your barel
Clean and lubricate your barel
fire first 5 44.0gn rounds at aimpoint 1
Clean and lubricate your barel
fire next 5 44.5gn rounds at aimpoint 2
do this for all 7 loads.

you will clearly notice a tightening of your group, in my case the result was

44.0gn 1
44.5gn 3/8
45.0gn 1/2
45.5gn 3/8
46.0gn 3/8
46.5gn 1
47.0gn 1 1/2 - 2 inch group at 100M

you then would repeat this test in my case concentraiting on the 45gn load.

if you were to put this load in another 308 it could shoot crap, thats why its always best to work up a load for your own gun.

why do this, A 1" Group at 100M will turn into a 2+ inch group at 200M etc..

cheers..