Post by Richard on Dec 1, 2015 21:46:54 GMT -5
Three way 10/60 duplex…………..
Got to the range this a.m. with almost rain conditions but lucked out without a drop! Foggy and 45 with no wind. This past week Panhandle was questioning about mixing duplex loads. I indicated that I had done that on purpose in the past just to see the results. To the best of my recollection, and altering of the way the duplex was put down the bore resulted in lower velocities. I have to admit that when I did this, it may not have been with Clays or even 4198 as the booster and main charge. Possibly N-110 with 4198 or 322. Been a while. In any event I went ahead with the test.
First I wanted a base line so, starting with a clean barrel I fired a five shot group using a 250 gr. XTP with the 10/60 Clays/H-4198 duplex. While the first shot was out of the group, the last four were pretty decent at 1.2” with an average velocity of 2839 fps and a 24 fps ES.
Note: I am going to start listing my Horizontal and Vertical spreads just for my own reference since I only keep my hand drawn bulls eyes.
Next up, I took the vial of Clays and 4198 and thoroughly mixed them together. To my surprise, the velocity increased somewhat? Here my average velocity was 2875 with an ES of 13 fps for four shots. (only had 8 XTP’s left so only a four shot group)
For the final test, I loaded the 4198 first, followed by the Clays. I was aiming at one of the upper bulls on my target frame. The shot went off at 2640 fps, some 200 fps slower than the standard duplex and, no sign of the bullet hole?..........So, I loaded another and aimed at a bull about 6” lower…again, a lower velocity and no sign of the hole??? For the third shot, I went to a bull at the bottom of the frame and had Bill watch in his spotting scope…………..Well now, the velocity went up to 2744 fps (only 100 fps slower) and Bill said the shot hit the dirt about 2’ higher than my POI and 2’ to the right!
For the fourth and final shot, still using the same POI the shot went off at 2722 and just nicked the aiming point? Go figure? All I can say is erratic! Probably something to do with the booster igniting at some point going down the barrel and screwing things up!
So there you have it Zen. Mixed load (at least this one) pretty good results. Loaded backwards poor results.
Moving out to 300 yards and trying to duplicate the 275 BE load from last week (5/65—4759/H-4198) I got mixed results? First three shots in 2” about two inches high………then the last two, an inch low and 4” to the left but only ½” apart?
This caused me to take a good look at the 8 x 32 NF scope and its mountings? Checked all screws and bolts and for any play in the mount. Nothing!
With that, I went to the same charge and the 300 gr. SST; also, no scope change. I fired an eight shot group that went 4.2” with 3 (in a row) going 1.5” and the best seven at 2.7”.
What I also highlighted in green was shots #4 and #5. Both only 1 fps apart yet these were the two furthest apart?
Average velocity here was 2751 with a 23 fps ES for eight shots.
Based on pretty good consistency, I do not think there was any scope/mounting issues. Just confusion on why those last two shots with the BE’s went low and together?
Moving on to the last group of the day, still using the 300 SST but with the 10/60 Clays/4198 duplex, I got an average velocity of 2735 with an ES of 9 and a group of 1.5 for three shots.
post a picture
screen shot on windows
Got to the range this a.m. with almost rain conditions but lucked out without a drop! Foggy and 45 with no wind. This past week Panhandle was questioning about mixing duplex loads. I indicated that I had done that on purpose in the past just to see the results. To the best of my recollection, and altering of the way the duplex was put down the bore resulted in lower velocities. I have to admit that when I did this, it may not have been with Clays or even 4198 as the booster and main charge. Possibly N-110 with 4198 or 322. Been a while. In any event I went ahead with the test.
First I wanted a base line so, starting with a clean barrel I fired a five shot group using a 250 gr. XTP with the 10/60 Clays/H-4198 duplex. While the first shot was out of the group, the last four were pretty decent at 1.2” with an average velocity of 2839 fps and a 24 fps ES.
Note: I am going to start listing my Horizontal and Vertical spreads just for my own reference since I only keep my hand drawn bulls eyes.
Next up, I took the vial of Clays and 4198 and thoroughly mixed them together. To my surprise, the velocity increased somewhat? Here my average velocity was 2875 with an ES of 13 fps for four shots. (only had 8 XTP’s left so only a four shot group)
For the final test, I loaded the 4198 first, followed by the Clays. I was aiming at one of the upper bulls on my target frame. The shot went off at 2640 fps, some 200 fps slower than the standard duplex and, no sign of the bullet hole?..........So, I loaded another and aimed at a bull about 6” lower…again, a lower velocity and no sign of the hole??? For the third shot, I went to a bull at the bottom of the frame and had Bill watch in his spotting scope…………..Well now, the velocity went up to 2744 fps (only 100 fps slower) and Bill said the shot hit the dirt about 2’ higher than my POI and 2’ to the right!
For the fourth and final shot, still using the same POI the shot went off at 2722 and just nicked the aiming point? Go figure? All I can say is erratic! Probably something to do with the booster igniting at some point going down the barrel and screwing things up!
So there you have it Zen. Mixed load (at least this one) pretty good results. Loaded backwards poor results.
Moving out to 300 yards and trying to duplicate the 275 BE load from last week (5/65—4759/H-4198) I got mixed results? First three shots in 2” about two inches high………then the last two, an inch low and 4” to the left but only ½” apart?
This caused me to take a good look at the 8 x 32 NF scope and its mountings? Checked all screws and bolts and for any play in the mount. Nothing!
With that, I went to the same charge and the 300 gr. SST; also, no scope change. I fired an eight shot group that went 4.2” with 3 (in a row) going 1.5” and the best seven at 2.7”.
What I also highlighted in green was shots #4 and #5. Both only 1 fps apart yet these were the two furthest apart?
Average velocity here was 2751 with a 23 fps ES for eight shots.
Based on pretty good consistency, I do not think there was any scope/mounting issues. Just confusion on why those last two shots with the BE’s went low and together?
Moving on to the last group of the day, still using the 300 SST but with the 10/60 Clays/4198 duplex, I got an average velocity of 2735 with an ES of 9 and a group of 1.5 for three shots.
post a picture
screen shot on windows
