Maineboy
06-07-2022, 12:59 PM
In another thread on this page, Marauder1 posted a reply and a link to this very comprehensive burn rate chart.
http://www.theballisticassistant.com/wp-content/uploads/2021/07/Powder-Relative-Burn-Rate-7-5-2021-Viewing.pdf
I've never seen this chart and I certainly wish I had a long time ago. My interest is in surplus CMR100 and always wondered where it fell on a burn rate chart. Loading data provided at the time I bought it suggested using IMR4895 data less 15%. Looking at the chart, I see it's faster than IMR3031 and H322...not what I was thinking at all. I've gone through most of an 8lb. jug of it and have another like it untapped on the shelf. For a long time, I could never get any decent results with it in both cast and jacketed loads except in my 45-70 Marlin. Most of my early experiences showed high-pressure signs or subpar accuracy. Recently I have had success shooting it in the 30-30 with the 150 grain Lee flat point boolit. Just two days ago I chronographed a few loads including one of 26.8 grs. of CMR100 and that Lee boolit and it averaged 1811fps with a SD of 5fps and an ES of 14fps. With excellent accuracy. This data is from my Savage 340 with an 18 inch barrel. I got this load by reducing the starting load of IMR4895 by 15%. As a comparison, the suggested starting load of 31.5 grains of IMR4895 and the same Lee boolit averaged 1965fps with a SD of 31fps and an ES 90fps and the max load of 33.5 grains of IMR4895 produced an average of 2138fps with an SD 14fps and an ES 38fps. Charges of 24 and 25 grains of CMR100 were less consistent but still fairly accurate. The chart indicated that Alliant Power Pro 1200R is immediately above CMR100 and Alliant data for 28.2 grains of it in the 30-30 with a 150 grain Speer jacketed bullet indicated a velocity of 2251fps. Optimistic maybe? For me, I have a little more knowledge of this powder and more loads to try.
http://www.theballisticassistant.com/wp-content/uploads/2021/07/Powder-Relative-Burn-Rate-7-5-2021-Viewing.pdf
I've never seen this chart and I certainly wish I had a long time ago. My interest is in surplus CMR100 and always wondered where it fell on a burn rate chart. Loading data provided at the time I bought it suggested using IMR4895 data less 15%. Looking at the chart, I see it's faster than IMR3031 and H322...not what I was thinking at all. I've gone through most of an 8lb. jug of it and have another like it untapped on the shelf. For a long time, I could never get any decent results with it in both cast and jacketed loads except in my 45-70 Marlin. Most of my early experiences showed high-pressure signs or subpar accuracy. Recently I have had success shooting it in the 30-30 with the 150 grain Lee flat point boolit. Just two days ago I chronographed a few loads including one of 26.8 grs. of CMR100 and that Lee boolit and it averaged 1811fps with a SD of 5fps and an ES of 14fps. With excellent accuracy. This data is from my Savage 340 with an 18 inch barrel. I got this load by reducing the starting load of IMR4895 by 15%. As a comparison, the suggested starting load of 31.5 grains of IMR4895 and the same Lee boolit averaged 1965fps with a SD of 31fps and an ES 90fps and the max load of 33.5 grains of IMR4895 produced an average of 2138fps with an SD 14fps and an ES 38fps. Charges of 24 and 25 grains of CMR100 were less consistent but still fairly accurate. The chart indicated that Alliant Power Pro 1200R is immediately above CMR100 and Alliant data for 28.2 grains of it in the 30-30 with a 150 grain Speer jacketed bullet indicated a velocity of 2251fps. Optimistic maybe? For me, I have a little more knowledge of this powder and more loads to try.