Other causes of poor accuracy

6

603Country

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i've had this old Ruger 77v since the early 80's. It has the second barrel now, and it has long been super accurate. The load used hasn't changed for decades (38.5 gr of IMR4064 behind a 55 gr Ballistic Tip). A couple of days ago I had the need to shoot it a bit, and was honestly shocked at the 1 1/2 inch groups. Had to be fouling, so I cleaned it, ran a couple of rounds through it, let it cool and shot some more ugly groups. Dang. I was hoping that the problem wasn't the barrel or the scope. Well, after a while, and some more frustrated shooting, I dug in the ammo can for some new Norma brass I knew was there. Loaded em up and shot tiny groups. It was the old, way-past-expiration date, brass that was my problem. Should have retired it long ago. Honestly would not have believed that the old work hardened brass was the cause of groups that ugly.

Just sharing this with you, so you'll factor the brass into your thinking when your shooting goes off on you.
 
Probably would have helped case life if I had annealed. At least it would have helped the necks. Before I decided to toss the whole lot, I was expecting a few neck splits. What I found was a loss of 50% of cases from split necks. That's when I just tossed them all. What I think is I just used the cases beyond their normally useful life.

For years I used only Norma brass in that rifle, and I got long life from it. Primer pockets got loose and I finally tossed all of them. Then couldn't find Norma 220 brass, so I bought WW Super. I don't have hard data to back it up, but I'm positive I got longer life from the Norma, which I never annealed.

I'm back with Norma brass again, though I will have to admit that the WW brass, after being well prepped and before it wore out, gave me terrific accuracy.
 
I have no idea what caliber you are shooting, or round count.

However, brass makes a big difference in group size. I loaded up some 308 ammunition using cases were I pulled the bullets. The gunpowder inside was old, causing corrosion issues on the bottom of the bullets, and when fired, the case necks crack. Most of them crack.

I took that stuff to blast away down at the CMP range in Talladega AL. I was surprised that groups were not bad at 200 or 300 yards, however at 600 yards, the stuff was all over the place. Cracked case necks make a heck of difference the further you go out. Which makes me believe that case neck tension is important.

Brass is important, good brass is very important for best accuracy.
 
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