For the Primer Test I fired 12 groups at 100 yards. Average group was around 1.5”, which was not very impressive.
I have never had good performance from this rifle. It should be capable of steady sub 1.0” groups.
The Primer Test was shot in virgin cases, with 46.0 gr of N140 and the Sierra 155 at 2.790”. I want to do some tweaking to see if the groups can be shrunk. Same brass as the last test, but neck sized.
I will test 10 shot groups, so as to have a little more validity in the results. I have shot thousands of 10 shot groups and have noticed that the first 5 shots usually mean almost nothing.
So I have loaded 10 of the “standard” load (46 gr and 2.780”) and then 4 variations:
Same load with a tighter neck.
Same load with bullet seated longer (2.815”)
Standard load with 0.3 gr more powder (46.3gr)
Tight neck, bullet seated longer and 46.3 gr. (3 changes from standard load.)
I will also try the standard load with a muzzle brake and with a linear comp. I expect adding a muzzle device will increase group size.
I have never had good performance from this rifle. It should be capable of steady sub 1.0” groups.
The Primer Test was shot in virgin cases, with 46.0 gr of N140 and the Sierra 155 at 2.790”. I want to do some tweaking to see if the groups can be shrunk. Same brass as the last test, but neck sized.
I will test 10 shot groups, so as to have a little more validity in the results. I have shot thousands of 10 shot groups and have noticed that the first 5 shots usually mean almost nothing.
So I have loaded 10 of the “standard” load (46 gr and 2.780”) and then 4 variations:
Same load with a tighter neck.
Same load with bullet seated longer (2.815”)
Standard load with 0.3 gr more powder (46.3gr)
Tight neck, bullet seated longer and 46.3 gr. (3 changes from standard load.)

I will also try the standard load with a muzzle brake and with a linear comp. I expect adding a muzzle device will increase group size.