New Pressure traces...
Dec 21, 2010 21:05:50 GMT -5
Post by Richard on Dec 21, 2010 21:05:50 GMT -5
Well, today the weather down here in Hickory NC started out around 34*, cloudy with a little frozen rain on the ground but "still" as you could want it to be for shooting. Perfect conditions for Herman and John's 300 yard shooting. John is a club member and good friend of Herman's but rarely gets to the club to shoot. As you could see from Herman's post, he is a good trigger puller ;D
Anyway, I got the Trace instrument set up and as usual it give me a pain in the butt trying to get it to communicate with the computer.......but eventually the two "talked!"
Edge wanted me to try shooting straight N-110 to see the sharp spike on the graph so not having used it as a single, I did not go overboard. 50 gr. with a 200 XTP saboted (I only shoot the blue Harvester smooth variety) The first shot was a fouler but did hit by the dot. I then did something with the computer and lost the trace The second shot (which is listed as the 1st.) I inadvertently left my aluminum muzzle bore guide on the rifle and proceeded to shoot it somewhere down range . Note the velocity was not effected and the pressure trace normal and the shot actually hit 6" low and 1.5" to the right (its an unmarked shot on the target board)
Note: For T-1 and T-2 I upped the "trigger sensitivity to 10"
T-2 was straight 60 gr. H-4198 with a 200 gr. sabot less .45 XTP.
T-3 was the same 60 gr. H-4198 with a 230 gr. XTP
Next I wanted to shoot 250 XTP's with the same load but I ran into a problem. The bullets which I had resized, must have "sprung back" as Bill and I had to literally hammer my new brass rod with a leather mallet which took almost five minutes to do. Man was that tight! You should have seen the look on this guy John's face when he found out I was going to shoot it!!! He actually left the range house ;D Well, needless to say, it fired with no problem. I did not save the trace since I was not going to go thru that routine again. The velocity was 2671 fps and the pressure was 34,000 psi.
The rest of the groups/trace's are pretty much self explanatory with the exception of T-6. You will note one red odd blip which is listed as #1? What happened here is that the rifle failed to fire. The firing pin fell and I got a click. I opened the bolt and examined the primer which had not fired and found a light hit on the cup. I re-inserted it (not looking at the computer which is now off the right of me and facing away) and it fired ok! As did the rest of the string. So, that blip is the result of a "click"
Also note: From T-3 thru T-7, I re set the sensitivity to 5 since I was getting a lot of false trace's from handling the rifle. As long as I found them prior to the next shot, the instrument allows me to delete them. There is no way that you can "jump" over a good trace to delete a bad one that you had not removed. That is why I left that one on the graph.
Note also: In trace 3, the second fifth shots? They loaded extremely hard and the pressure showed it!
I am assuming Edge or one of the administrators is going to lock this thread so we can continue the discussion on another thread. I think you will find the new displays better since they include the velocity along with pressure and other information which if figured out how to enter ;D
Richard
Anyway, I got the Trace instrument set up and as usual it give me a pain in the butt trying to get it to communicate with the computer.......but eventually the two "talked!"
Edge wanted me to try shooting straight N-110 to see the sharp spike on the graph so not having used it as a single, I did not go overboard. 50 gr. with a 200 XTP saboted (I only shoot the blue Harvester smooth variety) The first shot was a fouler but did hit by the dot. I then did something with the computer and lost the trace The second shot (which is listed as the 1st.) I inadvertently left my aluminum muzzle bore guide on the rifle and proceeded to shoot it somewhere down range . Note the velocity was not effected and the pressure trace normal and the shot actually hit 6" low and 1.5" to the right (its an unmarked shot on the target board)
Note: For T-1 and T-2 I upped the "trigger sensitivity to 10"
T-2 was straight 60 gr. H-4198 with a 200 gr. sabot less .45 XTP.
T-3 was the same 60 gr. H-4198 with a 230 gr. XTP
Next I wanted to shoot 250 XTP's with the same load but I ran into a problem. The bullets which I had resized, must have "sprung back" as Bill and I had to literally hammer my new brass rod with a leather mallet which took almost five minutes to do. Man was that tight! You should have seen the look on this guy John's face when he found out I was going to shoot it!!! He actually left the range house ;D Well, needless to say, it fired with no problem. I did not save the trace since I was not going to go thru that routine again. The velocity was 2671 fps and the pressure was 34,000 psi.
The rest of the groups/trace's are pretty much self explanatory with the exception of T-6. You will note one red odd blip which is listed as #1? What happened here is that the rifle failed to fire. The firing pin fell and I got a click. I opened the bolt and examined the primer which had not fired and found a light hit on the cup. I re-inserted it (not looking at the computer which is now off the right of me and facing away) and it fired ok! As did the rest of the string. So, that blip is the result of a "click"
Also note: From T-3 thru T-7, I re set the sensitivity to 5 since I was getting a lot of false trace's from handling the rifle. As long as I found them prior to the next shot, the instrument allows me to delete them. There is no way that you can "jump" over a good trace to delete a bad one that you had not removed. That is why I left that one on the graph.
Note also: In trace 3, the second fifth shots? They loaded extremely hard and the pressure showed it!
I am assuming Edge or one of the administrators is going to lock this thread so we can continue the discussion on another thread. I think you will find the new displays better since they include the velocity along with pressure and other information which if figured out how to enter ;D
Richard