I need advice from the more experienced reloaders. I found the 140 grain Speer HotCor in 6.5mm for $15.95 a box a little over a year ago. I think they had been sitting on the shelf since before the spike in prices for copper and lead as all the other Speer bullets around them were about $6 to $8 more a box (even more expensive now). I grabbed 3 boxes of them at that price thinking that even if they didn't shoot well I could always use them as a plinking round in my CZ 550 Swedish mauser.
Speer #13 lists loads for a strong commercial action and it has Reloader 22 starting at 44.0g and going to 48.0g. I loaded 7 loads of 5 shots each at 44.0g, 44.7g, 45.4g, 46.1g, 46.8g, 47.5g, and 48.0g.
I fired the first four loads a few months back and the last three yesterday. The first thing I noticed with the initial load was I was 130 FPS faster than book. The book used a Ruger with a 22" barrel while mine has a 23.6". Still, that was a bit surprising as it seemed faster than it should have been with only a 1.6" difference. There didn't seem to be large climbs in velocity between the first 4 loads. In fact, they seemed surprisingly small.
Fired in December or perhaps January
Load #1 @44.0g Reloader 22: av vel 2579, E.S of 26, Std. Dev of 9.08
Load #2 @44.7g Reloader 22:av vel 2582, E.S of 61, Std. Dev of 20.07
Load #3 @45.4g Reloader 22:av vel 2606, E.S of 92, Std. Dev of 35.34
Load #4 @46.1g Reloader 22:av vel 2629, E.S of 40, Std. Dev of 14.75
So, we see a difference of average velocity of 3fps from 44.0 to 44.7 grains?! Then, we get a 24fps bump at 45.4g and a 23fps bump 46.1g.
Here's where things get even more interesting (Fired yesterday)...
Load #5 @46.8g Reloader 22:av vel 2705, E.S of 121, Std. Dev of 41.52 (the first shot fired from a clean barrel chrono'd at 2628 but all the rest were above 2700)!
Load #6 @47.5g Reloader 22:av vel 2713, E.S of 53, Std. Dev of 21.16
Load #7 @48.0g Reloader 22:av vel 2769, E.S of 35, Std. Dev of 13.27
Now, it was around 35F to 31F when these shots were fired. I don't know the temp when the first 4 loads were fired, but it was likely only a 10 degree difference in either direction.
The cases were all new, never fired Winchester brass.
The primers were CCI 200 from the same box.
The powder was from all from the same canister.
Each charge was hand measured across all loads.
The seating depth was the exact same in all cases (3.107" / 0.015" from the lands).
The same chronograph was used both times (Shooting Chrony Beta Master)
Now, for those of you who are not familiar with the Swedish mauser, velocities in the range of 2,550 fps to 2,650 fps are common. Having velocity of 2,769 seems... Surprisingly the max loads also gave me the best grouping (1.596" including the 5th shot, a called flyer. 1.031" without).
Is this normal? I've only had my chronograph for a year and not much opportunity to use it. This is the first load I've chrono'd from start to finish.
Do you commonly see jumps like this? Is that normal?
Speer #13 lists loads for a strong commercial action and it has Reloader 22 starting at 44.0g and going to 48.0g. I loaded 7 loads of 5 shots each at 44.0g, 44.7g, 45.4g, 46.1g, 46.8g, 47.5g, and 48.0g.
I fired the first four loads a few months back and the last three yesterday. The first thing I noticed with the initial load was I was 130 FPS faster than book. The book used a Ruger with a 22" barrel while mine has a 23.6". Still, that was a bit surprising as it seemed faster than it should have been with only a 1.6" difference. There didn't seem to be large climbs in velocity between the first 4 loads. In fact, they seemed surprisingly small.
Fired in December or perhaps January
Load #1 @44.0g Reloader 22: av vel 2579, E.S of 26, Std. Dev of 9.08
Load #2 @44.7g Reloader 22:av vel 2582, E.S of 61, Std. Dev of 20.07
Load #3 @45.4g Reloader 22:av vel 2606, E.S of 92, Std. Dev of 35.34
Load #4 @46.1g Reloader 22:av vel 2629, E.S of 40, Std. Dev of 14.75
So, we see a difference of average velocity of 3fps from 44.0 to 44.7 grains?! Then, we get a 24fps bump at 45.4g and a 23fps bump 46.1g.
Here's where things get even more interesting (Fired yesterday)...
Load #5 @46.8g Reloader 22:av vel 2705, E.S of 121, Std. Dev of 41.52 (the first shot fired from a clean barrel chrono'd at 2628 but all the rest were above 2700)!
Load #6 @47.5g Reloader 22:av vel 2713, E.S of 53, Std. Dev of 21.16
Load #7 @48.0g Reloader 22:av vel 2769, E.S of 35, Std. Dev of 13.27
Now, it was around 35F to 31F when these shots were fired. I don't know the temp when the first 4 loads were fired, but it was likely only a 10 degree difference in either direction.
The cases were all new, never fired Winchester brass.
The primers were CCI 200 from the same box.
The powder was from all from the same canister.
Each charge was hand measured across all loads.
The seating depth was the exact same in all cases (3.107" / 0.015" from the lands).
The same chronograph was used both times (Shooting Chrony Beta Master)
Now, for those of you who are not familiar with the Swedish mauser, velocities in the range of 2,550 fps to 2,650 fps are common. Having velocity of 2,769 seems... Surprisingly the max loads also gave me the best grouping (1.596" including the 5th shot, a called flyer. 1.031" without).
Is this normal? I've only had my chronograph for a year and not much opportunity to use it. This is the first load I've chrono'd from start to finish.
Do you commonly see jumps like this? Is that normal?