I am pretty new to reloading and someone told me I should reduce the powder charge by 10% with military brass over non military brass . Is this true? Thank you all.
I am pretty new to reloading and someone told me I should reduce the powder charge by 10% with military brass over non military brass . Is this true? Thank you all.
In 308 and 30-06 it holds true quite a bit as the brass is thicker, and has less internal case volume.
In 223/5.56, it doesn't hold true as some military brass it thinner than their commercial counterpart.
Always best to work up loads and watch for pressure signs. Even a different gun may not shoot a proven load in another gun, due to chamber differences.
Thank you. I should have stated that I was loading 556 and 223.
It's worth noting that there are no 5.56 reloading dies. All your 5.56 milsurp brass is going to be .223 Remington after you resize it.
If you think there might be a difference in thickness among brass manufacturers, weigh it...it can't be measured with calipers.
All measurements want to compare apples to apples...
-compare once fired (1x) to once fired (better yet, use NEW brass)
-compare untrimmed to untrimmed, etc.
Then accumulate weight of a BUNCH of each and divide by the number of cases weighed to get an average. Now you're close to being able to say 'this brand must have thinner brass than that.'
But weight! (pun intended) there's more!
Now record the weights of each piece measured and compare it to the avg. weight you calculated (above.) Discard any that are SIGNIFICANTLY different than the avg.
Accumulate the avg. on the remaining set of cases and calculate the avg. again. Now you're really getting close.
Obviously only nerds, engineers and lab rats do this; but the Internet is FULL of comments about one brass being thinner than another and unless you see the 'raw data' you
have no idea whether they know what they're talking about.
OK; I was a lab rat - I have DONE this stuff and I've tried filling cases with water and weighing them, filling them with powder and weighing them, measuring the distance from
case rim to powder level, etc. all in an effort to determine whether one brand had more interior volume than another. (Indicating brass thickness variation.)
FAIL!
Fortunately, there are plenty of image-filled tutorials in reloading manuals (and doubtless online) from which to learn to READ PRESSURE SIGNS in cases.
Then follow the basic rule; back off a bit and work up the load for YOUR gun (remember, chambers are ALL DIFFERENT, too) because other people's data
don't apply to you!
When starting out in reloading it's valuable to remember that since the very first gun was made, the entire game is creating pressure from which the ONLY escape
is by moving the projectile(s) down the bore and out. If the bullet can't get out, you are holding a hand grenade.
If you didn't see it elsewhere, watch this 29 second video - watch the woman; watch her 7th shot and study her hands as she prepares for the 8th.
Click, but no BANG! Check the bore!
Her 7th round plugged the bore; her 8th round created pressure from which there was no escape... basic firearm theory defeated. She created a hand grenade.
Reloading centers around learning to create and control pressure.
Keep asking questions.