So, I was out testing my loads for a cz 550 american today. So, I mounted a brand new Swarovski z3 scope, built up my reloads, and set up my range. Please note that I didn't try any bore sighting, or adjust the scope in any way other than to level it with a Wheeler delux scope leveling kit...
I set up the target at 215 yards, and set up a bench on the back of a side by side tailgate...
I won't tell the load range, but I will say that I was well above current book loads using IMR 7828, remington 9.5 primers, Matrix 150 gr flat base bullets, and Winchester brass... I had found some loads in an older Lee book and verification of the load a few places online. So, I started 10% backed off rounded up... Increased each shot till a grain below that max load by .5 gr per load, Then at the one gr below that load, I increased by .2 gr per load. And for .5 gr above that load I increased .1 gr.
I'd fire a shot, go and mark it, come back to the rifle, and use an infrared thermometer to make sure that the barrel was exactly the same temp between each shot. In this case, I made sure that the barrel was 9*C for each shot. With it being 5*C out, that wasn't too bad to do. Barrel seems to cool fast on that gun...
Anyways, it was interesting that the rifle was starting to group really well at the mark of 1 .2gr load below the load I wanted to use and test... But, as I climbed higher, the loads got tighter and tighter. The hottest three loads at .1gr apart grouped small enough to be covered by a toonie. .855" to be exact. And right on level with the aim point. Just 3" to the left of the aim point. I think that some of them could have been tighter, but I may have pulled the shots due to being hungry and not forcing myself to concentrate as well...
I found it interesting that the scope came so close to lining up without being 'sighted'. Also, there were no pressure signs well above today's book max. I was carefully watching and measuring...The primers were not flattened, pierced, etc., and the cases were not bulging. There was no brass flowing into the ejector slot. I had less trouble extracting, than I did with loading into battery... Some of them were a bit tough turning the handle all the way down.
However, the ammo was cold. I never checked the temp of the ammo casings to see what temp it was at. I was thinking that testing the loads at several different temperatures, such as -30*C, Around the freezing point, and maybe +35*C and seeing how it grouped would be an interesting exercise.
As a side note, has anyone used an air compressor with an air nozzle to cool down a barrel faster??
I set up the target at 215 yards, and set up a bench on the back of a side by side tailgate...
I won't tell the load range, but I will say that I was well above current book loads using IMR 7828, remington 9.5 primers, Matrix 150 gr flat base bullets, and Winchester brass... I had found some loads in an older Lee book and verification of the load a few places online. So, I started 10% backed off rounded up... Increased each shot till a grain below that max load by .5 gr per load, Then at the one gr below that load, I increased by .2 gr per load. And for .5 gr above that load I increased .1 gr.
I'd fire a shot, go and mark it, come back to the rifle, and use an infrared thermometer to make sure that the barrel was exactly the same temp between each shot. In this case, I made sure that the barrel was 9*C for each shot. With it being 5*C out, that wasn't too bad to do. Barrel seems to cool fast on that gun...
Anyways, it was interesting that the rifle was starting to group really well at the mark of 1 .2gr load below the load I wanted to use and test... But, as I climbed higher, the loads got tighter and tighter. The hottest three loads at .1gr apart grouped small enough to be covered by a toonie. .855" to be exact. And right on level with the aim point. Just 3" to the left of the aim point. I think that some of them could have been tighter, but I may have pulled the shots due to being hungry and not forcing myself to concentrate as well...
I found it interesting that the scope came so close to lining up without being 'sighted'. Also, there were no pressure signs well above today's book max. I was carefully watching and measuring...The primers were not flattened, pierced, etc., and the cases were not bulging. There was no brass flowing into the ejector slot. I had less trouble extracting, than I did with loading into battery... Some of them were a bit tough turning the handle all the way down.
However, the ammo was cold. I never checked the temp of the ammo casings to see what temp it was at. I was thinking that testing the loads at several different temperatures, such as -30*C, Around the freezing point, and maybe +35*C and seeing how it grouped would be an interesting exercise.
As a side note, has anyone used an air compressor with an air nozzle to cool down a barrel faster??
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