Post by picklehead on Nov 17, 2019 15:40:38 GMT -5
Awhile back, we was talking about barrel temp. Since I was shooting a good bit today and it is 44 degree here, it would be the day for a test. 6.5x300 and pencil barrel or #2 as Weatherby claims. It is a damn pencil barrel to me. Rounds was set outside so they would be 40 to 44 and the rifle fell to 53 when I started. First shot and OUTSIDE of barrel went from 53 to 68.4 degree. Second went from 67.2 to 83.1 and stopped. I put a 10K thermistor in the barrel , at same place outside is being read and both was about 6 inches from lead of lands/groves. Takes a few seconds for the inside thermistor to stabilize and didn't take a reading right away. I waited until the temp meter hit 76.0 and the ohms was 10.35 / about spot on. 53 is 18.377 and got 18.27 so things is very close and not off by more than 1/2 to a full degree. The thermistor that I used is metal and fits just right in the .264 dia pipe. Bolt was closed soon as it was fired to keep the wind out.
Short and sweet. I didn't see any huge differ from inside of pipe to outside. 4 degrees was the highest and most was 1 to 2.5 degree differential. It seem like a constant 15 degrees was gained in barrel temp for each shot. 53 68 83 So there it is and don't know what a heavy barrel does but we know what a pencil 26 inch pipe reads.
77 is 9,999 and you can see 10.06 on the multi meter/thermistor. I really don't think we care about .007 differ and don't even know how to read that anyway. It may be close to a tenth of a degree if that matters. Now for the groups, not sure and haven't went to the 200 yard target yet. N165 and US869 was used if that matters also. No way in hell that I could take readings fast enough to see if one powder burns hotter than the next. US869 is what gave the constant 15 degree climb for each firing and didn't run but two of the N165 loads and got about the same.
Short and sweet. I didn't see any huge differ from inside of pipe to outside. 4 degrees was the highest and most was 1 to 2.5 degree differential. It seem like a constant 15 degrees was gained in barrel temp for each shot. 53 68 83 So there it is and don't know what a heavy barrel does but we know what a pencil 26 inch pipe reads.
77 is 9,999 and you can see 10.06 on the multi meter/thermistor. I really don't think we care about .007 differ and don't even know how to read that anyway. It may be close to a tenth of a degree if that matters. Now for the groups, not sure and haven't went to the 200 yard target yet. N165 and US869 was used if that matters also. No way in hell that I could take readings fast enough to see if one powder burns hotter than the next. US869 is what gave the constant 15 degree climb for each firing and didn't run but two of the N165 loads and got about the same.