Largest objective was to develop safe and reliable load with Rocky Mountain Reloading 69-grain bullet.

No accuracy testing was performed. The rifle was simply fired in a manner to avoid striking the chronograph. No target was downrange except the dirt in the berm.

General objectives:
•Develop reliable loads with TAC and AA2520 powders
•Develop reliable loads with 69-grain BTHP Rocky Mountain Reloading (RMR) bullets
•Develop reliable loads with 62-grain FMJ Hornady bullets

Gun used for testing was AR15 service rifle with White Oak upper. Barrel has about 4000 rounds on it.

Observation:
•CCI 450 (small rifle magnum) primers are less likely to pierce than the recovered .30 carbine primers from gibrass.com
•The current batch of recovered .30 carbine primers (gold color) seem a little less likely to pierce than the previous (silver color) lot
•RWS brass is significantly heavier than Lake City brass.
•RWS brass processed by Blue Ridge Brass needs to be run through the small-base die before further use. I experienced several instances of the RWS brass failing to go into battery during cycling from the magazine, and which required that I “mortar” the rifle to free the seized cartridge from the chamber.
•Velocity differences for a given load, but using different brass(RWS versus Lake City versus Wolf) were insignificant.

Notes on seating depth:
•Non-cannelure bullets seated to 2.250” overall length
•Cannelure bullet (62 Hornady) seated to cannelure

Conclusion – the following five loads are good.
•77 SMK with 24.2 grains Varget with CCI 450 primer, or Wolf primer
•69 RMR with 24.0 grains TAC with CCI 450 primer
•69 RMR with 23.5 grains TAC with recovered .30 carbine primer
•69 RMR with 25.2 grains AA 2520 with CCI 450 primer or recovered gold-color .30 carbine primer
•62 Hornady FMJ with 24.0 grains TAC with CCI 450 primer or recovered gold-color .30 carbine primer





Raw data follows







24.2 VARGET
MEASURE NOMINAL – 28.4
77-grain Sierra MatchKing
LAKE CITY ONCE-FIRED
30 Carbine GOLD PRIMER
(one primer pierced)
2656
2704
2660
2671
2635
average2665


24.2 VARGET
MEASURE NOMINAL – 28.4
77-grain Sierra MatchKing
LAKE CITY ONCE-FIRED
CCI 450 PRIMER
2659
2671
2628
2682
2684
2654
2675
2709
2682
2662
average2670


24.2 VARGET
MEASURE NOMINAL – 28.4
77-grain Sierra MatchKing
WOLF 0X
WOLF PRIMER
2659
2675
2663
2682
2647
average2665


#################################

24.0 TAC
MEASURE NOMINAL – 24.4
69-grain  ROCKY MOUNTAIN RELOADING
LAKE CITY ONCE-FIRED
30 Carbine GOLD PRIMER
(one pierced primer)
2839
2822
2809
2836
average2826


23.5 TAC
MEASURE NOMINAL – 23.5
69-grain  ROCKY MOUNTAIN RELOADING
LAKE CITY ONCE-FIRED
30 Carbine GOLD PRIMER
2763
2792
2769-grain
2752
2756
average2766


23.0 TAC
MEASURE NOMINAL – 23.0
69-grain  ROCKY MOUNTAIN RELOADING
LAKE CITY ONCE-FIRED
30 Carbine GOLD PRIMER
2722

#################################

24.0 TAC
MEASURE NOMINAL – 24.4
69-grain  ROCKY MOUNTAIN RELOADING
RWS ONCE-FIRED
30 Carbine GOLD PRIMER
2830
2789
2808
2831
2817
average2815


23.5 TAC
MEASURE NOMINAL – 23.5
69-grain  ROCKY MOUNTAIN RELOADING
RWS ONCE-FIRED
30 Carbine GOLD PRIMER
2749
2760
2748
average2752



23.0 TAC
MEASURE NOMINAL - 22.8
69-grain  ROCKY MOUNTAIN RELOADING
RWS ONCE-FIRED
30 Carbine GOLD PRIMER
2690
2692
2680
2723
2696
2687
2665
2671
2694
2711
average2690



#################################

24.0 TAC
MEASURE NOMINAL – 24.4
69-grain  ROCKY MOUNTAIN RELOADING
RWS ONCE-FIRED
CCI 450
2787
2863
2755
2870
average2818


23.5 TAC
MEASURE NOMINAL – 23.5
69-grain  ROCKY MOUNTAIN RELOADING
RWS ONCE-FIRED
CCI 450
2790
2774
2796
2755
2755
average2774


23.0 TAC
MEASURE NOMINAL - 22.8
69-grain  ROCKY MOUNTAIN RELOADING
RWS ONCE-FIRED
CCI 450
2687
2665
2671
2694
2711
average2685


#################################

24.0 TAC
MEASURE NOMINAL – 24.4
69-grain  ROCKY MOUNTAIN RELOADING
LAKE CITY ONCE-FIRED
CCI 450
2839
2853
2792
2802
2796
average2816


23.5 TAC
MEASURE NOMINAL – 23.5
69-grain  ROCKY MOUNTAIN RELOADING
LAKE CITY ONCE-FIRED
CCI 450
2777
2800
2763
2777
2744
2775
2723
2739
2739
2734
average2757


23.0 TAC
MEASURE NOMINAL - 22.8
69-grain  ROCKY MOUNTAIN RELOADING
LAKE CITY ONCE-FIRED
CCI 450
2804
2740
2738
2741
2671
average2738



#################################

25.2 AA 2520
MEASURE NOMINAL – 25.9
69-grain  ROCKY MOUNTAIN RELOADING
LAKE CITY ONCE-FIRED
CCI 450
2832
2841
2828
2842
2832
average2835


24.7 AA 2520
MEASURE NOMINAL – 24.9
69-grain  ROCKY MOUNTAIN RELOADING
LAKE CITY ONCE-FIRED
CCI 450
(2 neck splits)
2683
2737
2744
2762
2722
average2729


24.2 AA 2520
MEASURE NOMINAL - 24.0
69-grain  ROCKY MOUNTAIN RELOADING
LAKE CITY ONCE-FIRED
CCI 450
2679
2678
2672
2678
2667
average2674.8



#################################

25.2 AA 2520
MEASURE NOMINAL – 25.9
69-grain  ROCKY MOUNTAIN RELOADING
LAKE CITY ONCE-FIRED
30 Carbine GOLD PRIMER
2847
2847
2852
2866
2848
average2852


24.7 AA 2520
MEASURE NOMINAL – 24.9
69-grain  ROCKY MOUNTAIN RELOADING
LAKE CITY ONCE-FIRED
30 Carbine GOLD PRIMER
2730
2800
2784
2785
2756
average2771


24.2 AA 2520
MEASURE NOMINAL – 24.0
69-grain  ROCKY MOUNTAIN RELOADING
LAKE CITY ONCE-FIRED
30 Carbine GOLD PRIMER
2710
2734
2748
2698
2676
2673
2672
2709
2734
2690
average2704




#################################

24.0 TAC
MEASURE NOMINAL - 24.4
62-grain Hornady FMJ
LAKE CITY ONCE-FIRED
30 Carbine GOLD PRIMER
2781
2821
2805
2780
2792
average2795



24.0 TAC
MEASURE NOMINAL - 24.0
62-grain Hornady FMJ
Winchester 1X  - 30 Carbine SILVER PRIMER
2697
2706
2696
2697
2678
average2694


23.5 TAC
MEASURE NOMINAL - 23.5
62-grain Hornady FMJ
LAKE CITY ONCE-FIRED
30 Carbine GOLD PRIMER
2726
2723
2712
2708
2654
average2704


23.0 TAC
MEASURE NOMINAL-  22.8
62-grain Hornady FMJ
LAKE CITY ONCE-FIRED
30 Carbine GOLD PRIMER
2644
2665
2621
2715
average2661

I believe the TAC load with the RMR 69's could carry a goodly bit MORE powder than was tested today.

One of the largest elements of my focus today was trying to figure out whether the recovered .30 carbine primers can be pushed to the same limits as CCI 450 primers.

The .30 carbine primers CANNOT be pushed like the CCI 450's.

FWIW, Quickload says you don't hit SAAMI maximum pressure even with a FULL CASE (100% loading density) of TAC using the 69's. - Which would be 26.0 grains and making 57,000 PSI, and 2,900 FPS.

SAAMI maxium for 5.56 is 62,366 PSI.

I'm not vouching for 26.0 grains TAC with the 69's. Because I have not tested anything that hot.

You probably saw my remarks yesterday regarding chronograph testing the 69 RMR with TAC.

The highest I went with powder charge in my testing yesterday was 24.0 grains with the 69 grain bullet.
I was getting about 2815 FPS with 24.0 grains.

So, is 24.0 grains the “right” load for that bullet?

Quickload suggests you can go all the way to 26.0 grains and a slam-full case, and still stay within SAAMI.
Note too, Quickload uses 29.89 grains H2O capacity for the calculation. If you measure yourself, or Google, you’ll find that number is a bit low.
Many reports of 223/5.56 case capacity indicate at least 30.5 grains H20 capacity. See https://loaddata.com/articles/PDF/BenchTopics%2087.pdf

And the old notion about “military brass” has less capacity DOES NOT apply to 223. This notion has been disproven over-and-over again. Military and commercial 223 H2O capacity is the same.

Attached File


The online resource for RAMSHOT powder lists just 24.4 grains TAC with a Sierra 69 at 61,609 PSI.
https://www.ramshot.com/wp-content/uploads/2020/08/WesternPowdersHandloadingGuide8.0_WEB.pdf


Attached File


That’s a pretty huge difference between Quickload and the RAMSHOT people.
I have no way of knowing how the RAMSHOT people came up with their numbers for 5.56 handloads.
The RAMSHOT people are also claiming that 24.4 grains TAC with a 69 will give 3,049 FPS.
To that I say just this: No. Fucking. Way.
There is no way an extra 0.4 grains TAC is going take you from 2815 fps to 3049 fps. No way.
The change in velocity yesterday from 23.5 grains TAC to 24.0 grains TAC was an increase in velocity of only about 60 fps.
Not 300 fps.

Quickload has been pretty good at predicting velocities that match actual chronograph numbers for 223 handloads.
If anything, Quickload has predicted higher velocities than actually were obtained – and from that, I would deduce that Quickload’s predicted pressures are higher than actual pressures for a given 223 load.
Curiously though, with TAC, Quickload is predicting only 2669 fps with 24.0 grains TAC. Yet the chronograph yesterday told us 24.0 grains TAC was pushing the 69-grain bullet at 2815 fps. Pretty big difference – and on the heavy side. Which makes me think Quickload’s prediction of 26.0 grains TAC with the 69 is an over-charge.

I’m going out tomorrow with TAC and the 69’s and LC 1x-fired brass with CCI 450 primers.
I’m going to give 24.0 grains TAC a good accuracy test.
I will try 24.5 grains for just a function test.
I won’t be using the chronograph, because I find it impossible to shoot at a target, and over the skyscreen-type chronograph without shooting holes in the chronograph device.
But, I’m figuring the 24.5 grains to be at about 2875 fps.
I’d like to give the 24.5 grains a good accuracy test, but I’m shooting prone with a sling, and I’m testing THREE different uppers. I can’t deliver my best performance prone for more than about 60 shots. I’m going give all I’ve got for a single session to the 24.0 grain load.

Ok sitting at the bar drowning my sorrows after today’s range fukery.

Good news is the 24.0 TAC in a once-fired case prepped to 1.750 with a burr on the mouth is GOOD TO GO with the Rocky Mountain Reloading 69 BTHP.

Them bullets shoot good.

I shot a bunch of 10-shot strings with different uppers and different scope. Now I gots a solid 200-yard zero for them scopes with the 24TAC69RMR load.

All firing done at 200 yards. Sling supported only, with a Creedmoor shooting jacket.

For this pic, the upper is a White Oak Armament 5.56 service rifle upper with a 4x Hilux scope. My sight picture is the round target-bull on top of the reticle circle. Trying to center the bull on the little crosshair inside the circle gives me brain spasms. So I just make a two-ball snowman and SEND IT.

The target is one of those SHOOT NC splatter targets. The inner yellow circle pretty much conforms to the X-ring for the 200-yard reduced 600-yard target. The next yellow ring is a little small to match the reduced 600 10-ring. That smaller orange ring is the standard 7-inch 10-ring for the normal 200-yard SR target

So I’m going along thinking, “Yeah, this gonna be a good one. Firing the rounds from the magazine instead of single-loading. Get to the LAST ROUND, send it, thinking, “Yeah, that’s a good one. Check the spotting scope for bullet impact location. FuuuuuUuuuuUUUUUCCCCCKKKK!!! Way out a 3 o’clock. I got damn sure didn’t see it go there in the sights.

Made me so mad, I gave myself a Mulligan, and shot an 11th shot because I couldn’t believe that last-shot-out-of-the-magazine shit. Mulligan 11th shot landed right there in the rest of the knot.

Just fugk me.

Attached File

I promised I would test an extra half grain of TAC with the 69 RMR bullet.

24.5 grains TAC.

Only fired 10 shots. Seems plenty accurate. But noticed the brass on the case head was extruding into the ejector hole on the bolt pretty significantly. Not worth that feature for an extra 60 FPS.

This splatter target mimics the standard SR target. X-ring (3 inches) is about same size as 10-ring on reduced 600-yard target.

That 7 o’clock shot was first shot. Clicked up a quarter and right a quarter. Going along good. Got to that last shot out of the magazine. Again: FUUUUUuuuuuUUuCCKKK!!!
Out at 3 o’clock AGAIN!
WHAT is up with this last-shot shit???

I seen that 4 o’clock shot go there. That’s on me. But that widest 3 o’clock shot broke clean as a whistle. Not way out there.

Interesting.

Attached File

On days like this, I suggest you carry a known “good” load.

Suppose you are having a bad time with test loads. You then get frustrated and would be better off stopping and testing yourself and the gun with some reference ammo.

If the reference ammo throws flyers, then we stop and debug the gun or the shooter rather than waste test loads.

BTW, four thousand rounds sounds like a pretty high round count if that bbl has been used for rapids in XTC. Are you sure that bbl isn’t toast?

Barrel length?

Service Rifle AR-15 barrel is 20”

Shot the 69 RMR again yesterday.

200 yards.

Prone with sling.

24.0 TAC

Magazine length in RWS case with burr left on the case mouth.

I’m getting more comfortable with the snowman sight picture using Hilux 4x scope. I did not disturb the reticle adjustment during the 10-shot string. Used the same dope that I used two days prior to shoot a match with same ammunition on electronic targets.

Inner ring on the splatter target is a bit large for x-ring on simulated 600 target. Second ring is a bit small for the simulated 10-ring.

I saw the 3 o’clock shot go wide right when I sent it. Blame me.

Attached File

Speaking of shooting electronic targets.

Shooting the 69 RMR’s Saturday in a 200-yard match.

I sucked massively on offhand. I believe this is my first true Yahtzee in all these years shooting the highpower game. And maybe it’s not a TRUE Yahtzee - because I didn’t have a miss. Though not for lack of trying! When I shot that 5, I was amazed it even made the scoring rings.what a terrible shot that was. The incredible irony was that I won the “Cold Bore X” award. Yes, first shot offhand was an X - as the reticle went screaming across the target as I yanked the trigger. “If it is downrange, it will be shot” is actually a thing.

I was trying to shoot the UBR stock fully extended in offhand position because I recently had good results shooting scope offhand with a normal A2 stock. Was NOT working for me with the UBR fully extended with my offhand position. My face wanted to rest in the gap between the cheekrest and the extendo-butt. Caused me to have a few true spaz shots. And had lousy zero to boot.

Attached File


I kind of got my shit together for slow-fire prone. But made the mistake of using a newish magazine for that stage. Which is ironic since each shot must be separately loaded for that stage. My old worn-out aluminum follower mag (with useful divot in the follower hump) allows me to carefully place each round atop the follower, and the ass end of the round will remain against the divot in a substantially forward position, greatly reducing the chance of me “crunching” the round when I trip the bolt release. The slick new follower kept allowing the cartridge to move into a perilous position during closing of the bolt.

I crunched two rounds during that stage.

I removed the crunched rounds from the gun, and reloaded with an undamaged round. But all that cussing and squirming in order to clear the crunched round  caused me to bollocks my position enough that when I sent each round, each went wide left, costing me an 8 and a 9 (shots 13 and 20). Curses!

But those 69 RMR’s with 24.0 TAC out of a burr-mouthed Lake City once-fired case did their part when I wasn’t making nut-behind-the-butt mistakes.

Attached File

Not sure what to conclude.  The 200 yard targets posted early look kind of meh.  But the later 600 reduced target looks better, especially when discounting the 2 called fliers.  I'm not too worried about Shot #2, that can happen as you and the gun are settling into a prone string, so not reading too much into that.  As to the group, well -  I will say, you can get that or better with Hornady 55 FMJ... at 200.  But, the 69's are appealing because those are 300 yard bullets, where the difference will matter. And maybe even 500 and 600 yard, in a pinch.  

As to velocity consistency, in my experience with Service Rifle out to 300 yards, it's mostly irrelevant and generally not a good coorelation to actual on-paper accuracy.  Despite common wisdom.  Mostly because an HBAR .223 barrel just doesn't whip, so it doesn't really matter where you are on the whip node when it leaves. And at that distance, drop differential is irrelevant.  At 600 it can matter a little, in the extreme, and especially if it's a lighter bullet like this one.  But even then, on-paper accuracy is more important than velocity consistency, or even absolute velocity; has been my own experience.

Now if the plan is to run this through a 16" skinny, that can be a different story, in my own experience at least.  Appologies if this is unwelcome input from the peanut gallery sir!   Thanks for the posts, looking forward to your continued updates as you go.  

You’re right about all that.

I have my good days and not-so-good days.

I get up in the morning and just try to make it to the end of the day without too many bad things happening. I have fair luck at that. Most days.

Put some oil on the  bolt

Time to go shoot the rifle

Attached File

Attached File


When the coast is clear, I drive with my knees…

Had one target to brag about today. That 5 o'clock shot was #4. I called it low. Seems like I often call a shot simply low, and actually it comes up between 3 o'clock and 5 o'clock. I guess when I see the gun dip, the mechanics of it carries it also to the east. Load is 25.2 grains Accurate Arms 2520 and 69 RMR bullet. Lake City once-fired case with trimming-burr still on inside and outside of case mouth. CCI 450 magnum primer. White Oak basic service rifle upper (no fancy-pants barrel) with around 1000 rounds on it. 200 yards as usual. Prone, sling-support only. HiLux XTC $400 scope 4x power. Aiming point is short-snowman. Put the black bull on top of the reticle circle. Close my eyes and jerk the trigger.

Attached File

Also had a decent target shooting the AA2520 powder with the Hornady 62-grain FMJ. Lighter load than the 69-grain load I just mentioned. Running one full grain less powder (24.2 grains) here. I didn't touch the knobs on the preceding target. I played with a few clicks on this one. First three shots were below the "waterline." So I put on one click up. And I shot the tallest high 9 out the top. So I took that click off. Finished the 10-shot string with that second 9. Still pretty decent for bulk FMJ bullets.

Attached File