First shot perfect, then goes to hell

[bigbull]

Did you measure the bullet diameters for variations? Bullet runout of your loaded rounds?
bigbull

 

[Boomer]

Factory ammo shoots fine. Cases look perfect. No feed, or ejection issues. The load I used is: 55gr Sierra PSP, 38.0 gr H380, Winchester large rifle primers. Brass is once fired Remington. The rifle is a Savage 12FVSS. I have shot this rifle lots with factory ammo (with no troubles), and thought I would try some reloads in it.

Here's what we know -
rifle works well with factory ammo
rifle refuses to group reloads, and condition worsens with string length
all components are new
.224, 55 gr Sierra
Winchester LR primers
H-380 powder
powder is within parameters for a 55 gr bullet
brass is once fired
brass all appears normal after firing

In my experience, any reasonable load from a loading manual will group reasonably when fired from a rifle in good condition. Switching components serves to tighten groups when ultimate accuracy is being sought, but in my experience there are few combinations that won't group at all. I do recall loading some Winchester .224 55 gr FMJ that grouped in 1 foot, but this was the exception rather than the rule. There seems to be something out of spec here, either with the rifle - which you have been unable to determine, or with perhaps one of the components. First off, dump all those Sierras out on the kitchen table, and ensure that they are all identical. If all appears normal, try another brand of bullet and see if the problem persists. If the brass was out of spec, you would notice it at some stage of the process. HMMMM, H-380, are you weighing charges or metering them. If you are metering them, how often do you check your powder measure?

 

[Win94]

.......................the prime reason why when you have a rifle that shoots decently , keep it.

...............it gets maddening jerking around with all the different variables that you have to eliminate.