Jester896
Senior Clown
boy! did I learn a few things today. Federal GMM AR primers have a little AR stamped on them...it sure makes checking primers difficult...looks like there is something wrong with all of them.
The other thing was a consistent 4.5# trigger pull is way more than twice what a 2.5# is...I sure made some shooting errors. Every time my right thumb gets on top of the stock I will make a left error...and I kept finding it almost on top...not a good day.
Here is and image of the ladder...
#1 that ES and SD looks great on the first one doesn't it!...velocity just not there.
#2 The error on the target (didn't record shot) threw that ES and SD out a good bit....but that one round sure spiked.
#3 We got a spike in that one too and it has the worse ES and SD
with the 20" barrel I am figuring I am going to be about 80 fps off published speeds but I am way more than that off.
Top case:
primer is backed out of the case maybe .001 and the shoulders are still at 0. Not enough pressure to make the head come back to the bolt face after the firing pin hit I am guessing. Primer edges still rounded.
Middle case:
primer flush with case and the shoulders are pushed out about .001 from where they started. Primer edges still rounded.
Bottom case:
primer flush with case bottom and shoulder are pushed out .003 from where they started. Primer edges still rounded....this may be filling the chamber.
I did let it cool between each 5 shot group. I kept feeling at the chamber and half way down to see if the barrel was hot and it wasn't. After the 3rd group, when I turned the radar off I noticed the heated portion of the barrel was from 1/2 way down and to the muzzle.
I think I am going to bump it up .2gr and see what I get....what are your thoughts? Maybe by then I can get that trigger adjusted better.
The other thing was a consistent 4.5# trigger pull is way more than twice what a 2.5# is...I sure made some shooting errors. Every time my right thumb gets on top of the stock I will make a left error...and I kept finding it almost on top...not a good day.
Here is and image of the ladder...
#1 that ES and SD looks great on the first one doesn't it!...velocity just not there.
#2 The error on the target (didn't record shot) threw that ES and SD out a good bit....but that one round sure spiked.
#3 We got a spike in that one too and it has the worse ES and SD
with the 20" barrel I am figuring I am going to be about 80 fps off published speeds but I am way more than that off.
Top case:
primer is backed out of the case maybe .001 and the shoulders are still at 0. Not enough pressure to make the head come back to the bolt face after the firing pin hit I am guessing. Primer edges still rounded.
Middle case:
primer flush with case and the shoulders are pushed out about .001 from where they started. Primer edges still rounded.
Bottom case:
primer flush with case bottom and shoulder are pushed out .003 from where they started. Primer edges still rounded....this may be filling the chamber.
I did let it cool between each 5 shot group. I kept feeling at the chamber and half way down to see if the barrel was hot and it wasn't. After the 3rd group, when I turned the radar off I noticed the heated portion of the barrel was from 1/2 way down and to the muzzle.
I think I am going to bump it up .2gr and see what I get....what are your thoughts? Maybe by then I can get that trigger adjusted better.
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