Originally Posted by
Distant Thunder
JD,
I don't know what is "considered to be normal" but in my .45-70 I just trimmed all my brass early last year after 5 years of shooting that rifle. I use Starline brass, which is in my experience has been excellent stuff. The rifle is a Hepburn with a tight paper patch chamber. None of my brass was more than 2.105" long, but they varied enough I felt it was time to get them all uniform again. I trimmed them to 2.095" and everything was good through last year.
I have never annealed this brass. They were all full length sized and fireformed five years earlier. I only use two dies in my loading process, a compression die and a Lee factory crimp die that I set to close up the mouth maybe .002" to keep the bullets from coming out as I lift my cartridges out of the ammo box. The bullets can still be pulled and reseated by hand, it is a very light "crimp". I use one .060 LDPE wad over 83 grains of Swiss 1 1/2. My bullets are patched to .4505" diameter, a snug fit in the bore, and are seated .085" into the cases.
I have never had a case failure with my brass in those 5 years. I shoot 3 to 4 Creedmoor matches a year with this rifle and a mid-range match when I can. My son usually shoots 2 Creedmoor matches with me using this same rifle. That's about 600 rounds a year figuring a few in maybe a little practice in my backyard at 200 meters.
I bought 300 cases 6 years ago and at last count I had 297, so somewhere in my travels I misplaced 3. My brass has been fired about 10 times each. I'm careful about cycling my brass through in a way that keeps the number of times a case has been fired very uniform throughout the lot.
Is this normal stretching? I don't know, it is what my experience has been.