As an update, I’ve been to the range a couple of times now with the Magnetospeed Sporter. Interesting results for sure! The expander mandrel likely helped with neck tension and as a consequence, velocity consistency. I tried 3 different loads and it seems that I’m in a stable velocity node and can keep the same velocity and an even lower ES with a charge that is .4gr lighter. Here is the data for the load I was using over the Chrony. So nice to finally have accurate data.
On my second range trip i took my Tikka in .223 and fired a load that I know to be accurate. I was surprised to see quite a large ES. This ammo has not seen an expander mandrel but has also used Redding FL dies and Lapua brass. I have an expander mandrel on the way and will also try a slightly reduced charge at a later date. Here is the data.
Interestingly, the lowest velocity speed for the group was the first shot I recorded and the 6th shot fired of the day through a barrel / rifle that hadn’t been fired in months. Any idea if / how many shots it takes to settle a dirty and cold bore?
If I remove the lowest entry the ES drops by 1/3.
On my second range trip i took my Tikka in .223 and fired a load that I know to be accurate. I was surprised to see quite a large ES. This ammo has not seen an expander mandrel but has also used Redding FL dies and Lapua brass. I have an expander mandrel on the way and will also try a slightly reduced charge at a later date. Here is the data.
Interestingly, the lowest velocity speed for the group was the first shot I recorded and the 6th shot fired of the day through a barrel / rifle that hadn’t been fired in months. Any idea if / how many shots it takes to settle a dirty and cold bore?
If I remove the lowest entry the ES drops by 1/3.
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