• New Contest Starting Now! This Target Haunts Me

    Tell us about the one that got away, the flier that ruined your group, the zero that drifted, the shot you still see when you close your eyes. Winner will receive a free scope!

    Join contest

ADG Brass Not Growing After multiple firings, would you still bump the shoulder?

kshea

Private
Minuteman
Jun 25, 2025
3
1
Alaska
Hey Guys,

I'm trying to dial in a picky 7PRC build with a proof pre fit and after learning that Hornady Brass can be sub par, I bit the bullet (bad pun) and picked up some ADG brass to work off of. I'm on 3 firings with it now, and surprised that the ADG brass has not grown at all even having been fired 3 times. Using a hornady headspace comparator, the virgin brass measured 1.8905 - 1.8910. After three firings, its still measuring the same at 1.8910, and still seems to chamber without issue. Because of this, I've just been full length sizing the brass with the smallest redding comp shell holder for a .000 shoulder bump (i.e. no bump)

In comparison, Hornady brass after two firings seemed to grow as much as 1.8925 - 1.8930 (which I'm assuming is softer brass). It seems like at this point, it just starts to get tight in the chamber.

So, for all you experienced handloaders out there, does this seem normal? Does it make sense that premium brass wouldn't grow to chamber size after three firings? Also, does it seem strange that virgin ADG brass would only be like 1 -1.5 thou smaller than my chamber right out of the get go? Lastly, if this all seems normal, would you bump the shoulder back .002 or continue to not bump the shoulder until the fired brass doesn't chamber anymore.

Thanks for any insight!!
 
  • Like
Reactions: simonp
Hey Guys,

I'm trying to dial in a picky 7PRC build with a proof pre fit and after learning that Hornady Brass can be sub par, I bit the bullet (bad pun) and picked up some ADG brass to work off of. I'm on 3 firings with it now, and surprised that the ADG brass has not grown at all even having been fired 3 times. Using a hornady headspace comparator, the virgin brass measured 1.8905 - 1.8910. After three firings, its still measuring the same at 1.8910, and still seems to chamber without issue. Because of this, I've just been full length sizing the brass with the smallest redding comp shell holder for a .000 shoulder bump (i.e. no bump)

In comparison, Hornady brass after two firings seemed to grow as much as 1.8925 - 1.8930 (which I'm assuming is softer brass). It seems like at this point, it just starts to get tight in the chamber.

So, for all you experienced handloaders out there, does this seem normal? Does it make sense that premium brass wouldn't grow to chamber size after three firings? Also, does it seem strange that virgin ADG brass would only be like 1 -1.5 thou smaller than my chamber right out of the get go? Lastly, if this all seems normal, would you bump the shoulder back .002 or continue to not bump the shoulder until the fired brass doesn't chamber anymore.

Thanks for any insight!!
I’m no expert here, but I’d guess your hornady brass with the 1.893” is a representation of your chamber. Did you pop the spent primers before taking measurements? If not that can really throw things off. As far as the other brass not growing I’ve never heard of something like that before. Dumb question, are you sure you have the correct “head” in your comparator gauge? Brass is clean, no debris on it? It’s weird if all that checks out you’re getting a tight bolt close on the adg. I’d bump it down .002 so the bolt will close easily on it. Hopefully someone more experienced will weigh in.
 
Not apples to apples, but my 223AI has never needed the shoulders bumped as they never grew and always drop right in after a little love on the base. Good thing for me as the Redding Comp bushing die won't go any further down in my Co-Ax.

If your cases chamber easily after running through your FL die, whether bumping the shoulder or not, what more do you need? If you are as anal as I, you can go to the trouble of pulling your firing pin and extractor and check if the bolt drops on a sized case with no or very very little effort. If this happens and no effort is needed, you should be golden.

The above paragraph is how I set up many of my FL dies. I'm older and lazier now and just bump .002" on boltguns. If factory ammo is available, I do my break in with it. I have found Lapua Brass usually needs a couple firings to get fireformed and the ADG brass maybe as hard.