Blue68f100
Member
I did some more testing with the best load from the previous load test.
https://www.thehighroad.org/index.php?threads/9mm-wsf-and-rmr-124gr-mw-test.904576/
I used my version of the Ransom rest, after I did some mods to try to correct some issues I was seeing. Or I thought I was.
5.0 gr of WSF was the best group when I did my initial screening. I loaded all these on my LNL-AP using the factory powder dispenser. WSP, Win Brass, 1.120" OAL
Test procedure.
Gun was clean to start the test. 10 rounds for setup.
Tension on rest was set not to auto reset. I had to push the arm down for each shot. This can and does effect POI, depending on how hard you push. I push only on the back of the arm, not touching the gun.
Note: My shooting bench is not solid. I got up every 10 shots to take photos, pickup brass. Since the rest is bolted and clamped it's not going to move on the bench. It's setting too low on the bench for me to look through the sight to see if it moved. So I'm probably getting some shift, but don't know how much. Bench weighs around 100 lbs, setting on top the ground. Plus another 160 with me setting down.
Wind was up variable 15-20 G30 (8:00) but the direction it was coming from was being blocked partially by my house. I also tried not shoot when the wind was high. At times it would drop down on very regular basis.
Target has a 2" BE with 1" outer rings.
25 yrd distance
5 Shots to confirm setup
5 shots (2nd mag)
10 shots
10 shots
10 shots
10 shots
-----------
50 total.
The photos show how the group progressed.
2 mags of 5 shots. A good start.
10 rounds added, a couple of high ones.
10 more rounds added. Still a few going high.
10 more rounds added
10 more making a total of 50 rounds
Crony data for 50 rounds
Av 1183 fps , ES 89 fps, SD 14 fps, low 1144 fps, Hi 1233 fps, Av PF 146
Max horz spread was ~2"
Vertical spread ~ 2.5"
I think the shift in POI is the gun's barrel locking up. This 1911 does not have what I call a hard fit. Since this 1911 has 2 uppers the fit is a compromise on slides to frame fit. What I'm seeing is particles of burnt powder and specs of brass interfering with the lockup. Which in turn pushes down on the rear of the barrel (locking lugs), adding more pressure to the barrel feet, kicking the nose up. Not sure there is anything I can do to correct this but will dig deeper.
The reason I think this is after cleaning the gun after the shooting 200 rounds. I normally don't clean but every 1000+ rounds. And the minor differences I can't shoot the difference. The Dot sight is not the best for precision either. The dot covers the BE at 25 yrds when on auto.The only way to get it smaller is to reduce the brightness, which makes it hard to see.
After shooting I decided to modify my rest again, so I can prevent the gun from rotating up. This was for purpose of trying to locate the POI shift. These targets show that some time is shifts down, sometimes up. The gun had 160 rounds put through it at this time. Look only at the group, target not in the same spot when I changed it.
https://www.thehighroad.org/index.php?threads/9mm-wsf-and-rmr-124gr-mw-test.904576/
I used my version of the Ransom rest, after I did some mods to try to correct some issues I was seeing. Or I thought I was.
5.0 gr of WSF was the best group when I did my initial screening. I loaded all these on my LNL-AP using the factory powder dispenser. WSP, Win Brass, 1.120" OAL
Test procedure.
Gun was clean to start the test. 10 rounds for setup.
Tension on rest was set not to auto reset. I had to push the arm down for each shot. This can and does effect POI, depending on how hard you push. I push only on the back of the arm, not touching the gun.
Note: My shooting bench is not solid. I got up every 10 shots to take photos, pickup brass. Since the rest is bolted and clamped it's not going to move on the bench. It's setting too low on the bench for me to look through the sight to see if it moved. So I'm probably getting some shift, but don't know how much. Bench weighs around 100 lbs, setting on top the ground. Plus another 160 with me setting down.
Wind was up variable 15-20 G30 (8:00) but the direction it was coming from was being blocked partially by my house. I also tried not shoot when the wind was high. At times it would drop down on very regular basis.
Target has a 2" BE with 1" outer rings.
25 yrd distance
5 Shots to confirm setup
5 shots (2nd mag)
10 shots
10 shots
10 shots
10 shots
-----------
50 total.
The photos show how the group progressed.
2 mags of 5 shots. A good start.
10 rounds added, a couple of high ones.
10 more rounds added. Still a few going high.
10 more rounds added
10 more making a total of 50 rounds
Crony data for 50 rounds
Av 1183 fps , ES 89 fps, SD 14 fps, low 1144 fps, Hi 1233 fps, Av PF 146
Max horz spread was ~2"
Vertical spread ~ 2.5"
I think the shift in POI is the gun's barrel locking up. This 1911 does not have what I call a hard fit. Since this 1911 has 2 uppers the fit is a compromise on slides to frame fit. What I'm seeing is particles of burnt powder and specs of brass interfering with the lockup. Which in turn pushes down on the rear of the barrel (locking lugs), adding more pressure to the barrel feet, kicking the nose up. Not sure there is anything I can do to correct this but will dig deeper.
The reason I think this is after cleaning the gun after the shooting 200 rounds. I normally don't clean but every 1000+ rounds. And the minor differences I can't shoot the difference. The Dot sight is not the best for precision either. The dot covers the BE at 25 yrds when on auto.The only way to get it smaller is to reduce the brightness, which makes it hard to see.
After shooting I decided to modify my rest again, so I can prevent the gun from rotating up. This was for purpose of trying to locate the POI shift. These targets show that some time is shifts down, sometimes up. The gun had 160 rounds put through it at this time. Look only at the group, target not in the same spot when I changed it.