5.56 AR Only Loads
- Thread starter padom
- Start date
now that i have a new barrel from craddock i figured it finally be time to start posting here
some interesting results friday trying out N540 and varget
craddock mk12mod1 18" 5.56 CP chamber
RMR 75gr 3GH
Lake City 5.56 mixed year brass
winchester small rifle AR primers
26.0grs of N540
avg 2924
ES 14
sd 5.5
from what i could see no cratered primers or ejector marks but it definitely sounded heavy
~ 1.5moa group but ive heard shortening the CBTO helps with this bullet
24.4gr Varget
avg 2730
ES 5
SD 2
again about 1.5 moa but with consistency like that there has to be a winning combo for seating depth
some interesting results friday trying out N540 and varget
craddock mk12mod1 18" 5.56 CP chamber
RMR 75gr 3GH
Lake City 5.56 mixed year brass
winchester small rifle AR primers
26.0grs of N540
avg 2924
ES 14
sd 5.5
from what i could see no cratered primers or ejector marks but it definitely sounded heavy
~ 1.5moa group but ive heard shortening the CBTO helps with this bullet
24.4gr Varget
avg 2730
ES 5
SD 2
again about 1.5 moa but with consistency like that there has to be a winning combo for seating depth
25 grains…and here I am unwilling to go over 24.5gr with 77 SMK and TMK in LC brass lol. Nice to see someone pushing the limits. I’ve never pushed it more due to the temperature instability and the heat where I live. This summer I’ve been getting consistently 2660 fps out of a 16” BCM CHF/CL barrel with ~85 degree morning shooting, and it was roughly 2630 when I did development at probably 45-50 degrees several years ago, and of course with a different lot of powder.
I haven’t noticed any pressure signs this summer with the exception being I’ve seen some shiny ejector spots fired only out of a BCM 11.5 CHF/CL. The load also shoots like crap out of that barrel but I’m not going to load specifically for it.
First batch of 77smk practice ammo done on my automated 5.56 1050.
This is my final PP2000MR load I worked up and tested in my 20" Geissele
American Reloading 77smk pulls
26.4gr PP2000MR
New Pulled Primed AAC 5.56 brass
2.245" COAL
2751
SD11
Because this was new pulled brass, neck tension was super light. So I threw a new toolhead on my 5.56 1050 and installed a Redding Competition 223rem Micrometer neck sizing die and then a 21st Century mandrel then a Lyman M Die. I ran all the brass through this toolhead to make all the necks nice and round again, squeeze them down, set 0.003 neck tension and m die so 77smk bullets dont topple off when loading feom the MBF.
Ran the first 500pc box of brass and bullets today. 3 more boxes to go. Gonna fill up an ammo can with 2000rd of this stuff for practice.
This is my final PP2000MR load I worked up and tested in my 20" Geissele
American Reloading 77smk pulls
26.4gr PP2000MR
New Pulled Primed AAC 5.56 brass
2.245" COAL
2751
SD11
Because this was new pulled brass, neck tension was super light. So I threw a new toolhead on my 5.56 1050 and installed a Redding Competition 223rem Micrometer neck sizing die and then a 21st Century mandrel then a Lyman M Die. I ran all the brass through this toolhead to make all the necks nice and round again, squeeze them down, set 0.003 neck tension and m die so 77smk bullets dont topple off when loading feom the MBF.
Ran the first 500pc box of brass and bullets today. 3 more boxes to go. Gonna fill up an ammo can with 2000rd of this stuff for practice.
My son and I tested the new 77smk run of ammo today in various uppers to get some data.
We chrono 10rd each in my 11.5" BCM, 12.5" Geissele and 16" Wilson Combat.
I originally worked this load up in my 20" Geissele so here the numbers.
77 SMK 26.4gr PP2000MR
20" Geissele - 2750
16" Wilso Combat - 2650
12.5" Geissele - 2486
11.5" BCM - 2357
I ran off 200pc of the same exact load above but with 77 TMK pulls at 2.26" COAL
77 TMK 26.4gr PP2000MR
16" - 2610
Rounds performed great from both the 12.5" Geissele and 16" Wilson combat at 300, 400 and 500yd.
Hit after hit at each distance. Red dot with 3x magnifier had to find the hold at 500yd but once you found it, it was hits over and over.
The 16" sports a March shorty 1-8. Just use the tree for holdover 500yd and it was all hits.
Very happy with this ammo. Not bad for a super cheap precision practice load with pulled components and PP2000MR i had 8 lbs of and had no use for that meters like water on the Dillon!
We chrono 10rd each in my 11.5" BCM, 12.5" Geissele and 16" Wilson Combat.
I originally worked this load up in my 20" Geissele so here the numbers.
77 SMK 26.4gr PP2000MR
20" Geissele - 2750
16" Wilso Combat - 2650
12.5" Geissele - 2486
11.5" BCM - 2357
I ran off 200pc of the same exact load above but with 77 TMK pulls at 2.26" COAL
77 TMK 26.4gr PP2000MR
16" - 2610
Rounds performed great from both the 12.5" Geissele and 16" Wilson combat at 300, 400 and 500yd.
Hit after hit at each distance. Red dot with 3x magnifier had to find the hold at 500yd but once you found it, it was hits over and over.
The 16" sports a March shorty 1-8. Just use the tree for holdover 500yd and it was all hits.
Very happy with this ammo. Not bad for a super cheap precision practice load with pulled components and PP2000MR i had 8 lbs of and had no use for that meters like water on the Dillon!
SD's more has to do with the type of powder than it being loaded on a progressive in my testing..
But with this specific load I posted above using PP2000MR my SD was 11 over 50rd
I have traditionally loaded everything, like M193, progressively except my SMK and TMK loads where I’ll trickle powder (TAC). But this takes so much time I’ve really thought about going back to loading these progressively as well. I don’t know if my testing is thorough enough because the last time I chronoed progressive loaded rounds years ago I had a string with like 13 SD (SMK) and a string with a 28 SD (TMK) at the same charge weight I normally use of 24.5gr.
However my typical trickling SD with both bullets lately is in the 12-19 range, bullet and barrel dependent, with the occasional sub 10 and greater than 20. So I don’t know that I gain much from trickling and seating individually either and plan to test this more. It takes way too much time just to load 50 rounds.
I dont get crazy low single digit SD's over real sample sizes of 50-100rd (i dont base my SD's off 5-10 shots) with TAC or PP2000..
I do my full load workup with all powders, including these loads being discussed on my A&D Fx120i...
After finding my load, I dial my 1050 in to match it. I tested 25 powder drops in a row from my 1050 powder measure with this 26.4gr PP2000MR load and they averaged 0.1gr consistency.
SD's were the same when thrown on my 1050 vs trickling them on my A&D...
Consistent hits out to 500yd tested yesterday with boring repeatability show they shoot just fine being thrown on the 1050.
I have tuned, polished and Micrometer adjustment installed on my dillon powder measures. They are very consistent
Yeah my strings are generally 30-40 rounds if I’m shooting groups before switching guns, but I’ve always found the Dillon powder measure to be as consistent as your stroke is. I’m sure being fully automated helps with that consistency however when I randomly check the throw it’s generally always no more than 0.1gr off anyway. Have you tested crimp vs no crimp with these loads?
I never found crimping to increase accuracy with proper neck tension. I generally setup my taper crimp die to close the bell on my rounds back to straight is all. When using a progressive with bullet feeder, especially when automated, you have to run an M die or flare die of some sort to get the rounds to stay on the case after being dropped out of the bullet feeding die so they dont topple off. So my crimp die is always set to close this bell back to straight.
But, I will say this 2000rd batch of 77smk I just ran, I did give it a little more crimp than normal into the cannelure and they are very accurate. I shot a group at 50 and 100 when zeoring my new March shorty on my 16" yesterday and they were stacking on top each other no fliers. So again, very happy with this cheap to make, super fast to make precision practice load.
Speaking of cheap practice rounds. lol
I was using some factory seconds and even though I got sub moa results most of the time I would get fliers. Sometimes just enough to wreck a cloverleaf and at the worst
bring it back to moa. In fact a lot of the time the load shot so well I forgot about the
factory seconds part.
I decided to try and figure out what the culprit was.
Manufacturing defects (seconds duh), tolerance stacking, inattention to detail,
bad luck of the draw (arbitrarily picking the shortest bullets to measure) and possibly
rounding off measurements for a "nominal" in the wrong direction. And a few generally poor decisions.
The factory packaged bullets had a 0.003 max to minimum on both base to ogive
and length dimensions. The seconds bulk packed had 0.010 length variance
and 0.006 base to ogive.
This put some bullets just at touch on the lands, not good for an AR. Remember the poor decision reference, I decided that a coal of 2.23 was a cool number, no it didn't
give enough jump for the longest of the bullets but sure was impressive with the others.
Luckily these bullets are known to be jump tolerant I will try another 0.010 thousands should ease my pain. I will have to live with the nominal coal now being 2.22
the horror, the horror.
Funny thing is if I had been using the good factory bullets it may never have came up
and been weight sorting by now. lol
I was using some factory seconds and even though I got sub moa results most of the time I would get fliers. Sometimes just enough to wreck a cloverleaf and at the worst
bring it back to moa. In fact a lot of the time the load shot so well I forgot about the
factory seconds part.
I decided to try and figure out what the culprit was.
Manufacturing defects (seconds duh), tolerance stacking, inattention to detail,
bad luck of the draw (arbitrarily picking the shortest bullets to measure) and possibly
rounding off measurements for a "nominal" in the wrong direction. And a few generally poor decisions.
The factory packaged bullets had a 0.003 max to minimum on both base to ogive
and length dimensions. The seconds bulk packed had 0.010 length variance
and 0.006 base to ogive.
This put some bullets just at touch on the lands, not good for an AR. Remember the poor decision reference, I decided that a coal of 2.23 was a cool number, no it didn't
give enough jump for the longest of the bullets but sure was impressive with the others.
Luckily these bullets are known to be jump tolerant I will try another 0.010 thousands should ease my pain. I will have to live with the nominal coal now being 2.22
the horror, the horror.
Funny thing is if I had been using the good factory bullets it may never have came up
and been weight sorting by now. lol
Measured things to hell and back.
The seconds kinda suck. Lol
The Sierra 69g smk's are giving me problems getting an accurate measurement to the lands.
I have cleaned the chamber and still not consistent.
Is there something about the bullet shape to ogive that's giving me a problem?
I have not yet got a Sierra manuel, I'm told they offer a separate set of loads for ar's?
I have a custom seating plug on order. I think the bullets are bottoming out in the stem.
The seconds kinda suck. Lol
The Sierra 69g smk's are giving me problems getting an accurate measurement to the lands.
I have cleaned the chamber and still not consistent.
Is there something about the bullet shape to ogive that's giving me a problem?
I have not yet got a Sierra manuel, I'm told they offer a separate set of loads for ar's?
I have a custom seating plug on order. I think the bullets are bottoming out in the stem.
I tried the SMK blem thing before, won’t do it again. Clearly several different lots as base to ogives were all over the place. Probably an extreme spread of at least 45 thousandths. With all the time spent measuring and sorting bullets, first quality SMKs is worth it to me.
@DeaconBlue
I hear you man.ypur running into lands or shoving ogive under crimp.
Moving goalposts in two directions will drive a man to ruin. Lol
I hear you man.ypur running into lands or shoving ogive under crimp.
Moving goalposts in two directions will drive a man to ruin. Lol
