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MEmeMEme
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Full.Lead.Taco
You shooting it in an ar15 or bolt gun? Subsonic or super? I have a palmetto pistol upper on order to do some testing on this mold. I want to see what it would take to get it to cycle in this upper at subsonic speeds. I also want to try it in a 1/7 twist bolt 223 gun. I will post my results when I have them, but if you want me to test something specifically, let me know.
MEmeMEme
Full.Lead.Taco
2 different schools of thought. One is to use a faster pistol powder such as Trailboss, but it might be tricky to get enough gas pressure for it to cycle. The second, is to use a slow burning rifle powder like RL22 or something with a similar burn rate and just have more unburnt powder coming out. As far as accuracy goes, I have not done much testing yet. I am waiting for my upper to come to test with.
picked this up off another website
This testing isn’t going as smoothly as I initally anticipated.
When I tested the inital load of 7.0 grains, I mentioned that I loaded ten. I fired five of them at a paper target to see if they grouped: I didn’t shoot them through a chronograph. Then I shot the other five through a chronograph. Out of those five I got three velocities that were very similar and I got two that were way off. So, I figured the chronograph didn’t pick those two shots up right and I threw those numbers out and reported an average velocity based on an average of only three shots (which was 942 fps). Now, based on my further testing, I think this is a bogus number. Maybe.
Several days after the first attempt I loaded up another 10 rounds and shot all of them over the chrono. I got seven numbers that were fairly close together for an average of 935 fps. Note that this is a 1/2 grain more powder than the previous test but a lower average velocity. But, since this test was based on seven rounds instead of three, I tend to put more faith in it. The high was 991 and the low was 869 with a spread of 122 fps.
Yesterday I decided to start getting serious about this. I loaded up thirty rounds and today I shot them over the chrono. I started off with 8.0 grains and got a nine shot average velocity of 1024 fps. The high was 1167 and the low was 948 for a spread of 219 fps Then 8.5 grains with gave me a ten shot average of 1045 fps. The high was 1226 and the low was 944 fps for a spread of 282 fps. Then 9.0 grains which gave me a ten shot average of 1201 fps. The high was 1291 and the low was 1075 fps for a spread of 216 fps.Put in easier to read format here is what I got, warts and all.
7.0 grains = 942 fps (?)
7.5 grains = 935 fps
8.0 grains = 1024 fps
8.5 grains = 1045 fps
9.0 grains = 1201 fps Notice Velocity dropoff … too much powderTrail boss
here is the article the info is from
http://www.silencertalk.com/forum/viewtopic.php?f=9&t=4632&start=0keithsharp
harmongreer
Ive tried them with no good results. Accuracy issues in my ar15 20 inch 1:7 and 1:8 twist guns. I tried 4198. Cfe223 and reloader 15. A few rounds fired with varget as well. Most of the rounds tumbled. I tried some loaded with red dot and they were ok but i wanted something that would cycle an ar15. Linotype. Wheel weights. And a blend of lino and wheel weights didnt work. These were powder coated and sized .225. I took the mold and shortened it by .250″ and will try again with a lighter bullet
My shortened bullets shot fast also performed terribly. 3.3 grains of titegroup and it was a tack driver. I loaded 25 grains of imr 4831 and the shortened bullet at 71 grains 20 inch 1:7 twist gun. Five rds at 20 yds wouldnt stay on an IPSC target. I tried 20 grains of cfe 223 and it was much better. More testing is certainly needed
keithsharp
harmongreer
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