Have an accurate AR, want to load PD ammo for it

[Nomo4me]

Well, I may pull it out when PD shooting. I might also just take it out on the desert and do some long range plinking with this gun.
I shot the group below with a new Rock River 24" Varmint AR 8" twist bbl. I want to load up some accurate ammo for it and have 500 rounds virgin LC brass primed, chamfered and deburred. Length is .004" under max and very uniform so I didn't trim it.

Ingredients I've got on hand to play with:

69gr HPBT match kings
50gr Blitz kings
55 v-max

Benchmark
Tac
Xterminator

I've got the Sierra manual which has separate data pages for AR vs Bolt guns, which is helpful. I've printed off Alliant's page for the 223, but some of their loads shown run to 62,000 psi and I don't want to run quite that hot.

I've never loaded for an AR before and would like to hear input/advice from those that have strived for 1/2 moa accuracy from their heavy bbl guns. I'll be loading on my LNL progressive press using Redding comp seating die.

Also, I presently only have a redding Type-S neck bushing and body dies for the 223. Which FL Redding die should I order to best work with my RRA's Wylde chamber? Bushing? I hate the thought of pulling an expander ball back through the neck - don't do it on any other reloading I do.

Thanks!

 

[Klong]

Good shooting!

I think you will like the 50gr and 55 gr bullets for PD. I would use the 77gr for long range plinking, due to better wind performance. I use a different powder, such as 748 or MR223 in mine for the lighter bullets. Varget and VV540 push the heavier bullets. Looks like you should do what you can to duplicate the factory 77 gr load!


I have shot many thousands of 223 rounds in competition and a few 1000 at PD, all were shot with the expander ball in my reloading die with no ill affects. I do polish the ball down to where it is doing very little work on the neck. I do not use the S full length die, I use a Lee full length and and RCBS full length die. The Lee gives me the least run out. Always full length size for AR's.

What trigger are you using?

 

[40X Guy]

23.5 grains of Benchmark with the 69 MK's loaded to mag length is a very good round in my AR, a good combo of accuracy and speed is still there, good out to 400 yards at least. Primers I use are the CCI BR-4's. My brass is Winchester so be careful with the LC brass.

Frank

 

[Nomo4me]

My gun has the RRA "national match" 2 stage trigger. A slightly mushy pull of about 1.5 lbs but I can live with it.

One other question, how does an AR gun show pressure signs?

 

[Redhighpower]

What is your barrel twist? I've only shot 69's, 75's, 77's SMK's and Hornady's. My AR Service is 1-7, the Flat Top 26" barrel is 1-8. I use R-15 and Varget. I load for Magazine length. Signs of High Pressure are when the primers are flattened or blown out. When that happenes drop .5 grains. I load Varget at 25.0 grains and R-15 at 24.0 grains. I get the same velosity with both powders, R-15 is hotter than Varget. I would start out one grain less than that and work up in 0.5 increaments. My primary shooting is across the course. Larry

 

[Nomo4me]

I use benchmark for all of my 6mm and smaller varmint loading and buy it in the 8lb jugs so was hoping to have it work out for my AR loading as well.
What would sway me to use TAC would be if it were noticably cleaner burning, though I've never considered Benchmark to be a dirty powder.

23.5 grains of Benchmark with the 69 MK's loaded to mag length is a very good round in my AR, a good combo of accuracy and speed is still there, good out to 400 yards at least. Primers I use are the CCI BR-4's. My brass is Winchester so be careful with the LC brass.

Frank

 

[pdog2225]

Check out the "articles" section on this site. The one for .223 and .223ai is loaded with good info. Near the bottom is chart of loads and I use this one.

"AA 2520 26.0 Rem 7.5 69 Sierra MK 3000 fps AR-friendly load. Very Accurate. Watch for powder lot variations though".

I have the same rifle as yours. Mine loves the 69smk and LC brass with a match primer. I get 2944fps and no pressure signs even in a dog town. It only takes 24.0 MOA to get to 1000yds. I also use a FL small base sizing die so my rounds can be shot in any .223. This is a ball powder, is not dirty and meters like water. pdog2225

 

[Larryh128]

My RRA gets fed 25grs of Benchmark with 55 gr bullets. Good load.

 

[TheOtherZilla]

My AR likes TAC and 50 grainers.. 55 also work but 50's are best in my rig. I have a 20" bull bbl 1:9. 1/2 inch groups or better are the norm.. Depending on your chamber you may need a small base die.. I get away w/o one but I bought one just in case.

 

[itchyTF]

Just a suggestion -
You say your brass is .004 under max. I assume that is published max. You ought to measure your chamber length so you'll know when to trim for sure and not risk pinching bullets.

 

[Klong]

Nomo4me, pressure in and AR first appears with clear ejector pin marks on the back of the brass. Depending upon which primer you use, you may see flat primers falsely indicating pressure. One very clear sign is when you start having primers fall out of the brass.

 

[Nomo4me]

I primed up with Rem 7 1/2's, not a hard primer. I like warm loads in my bolt guns. I'm not going to push this AR hard.

I'll test the 50gr Blitz king and 69gr SMK for accuracy. I'll try TAC and Benchmark behind them in .5 gr increments.
The 50gr Blitz Kings are what I use for Bolt 223's so in this gun I'm just testing them for curiosities sake. I'm wanting the 69 to be my go-to bullet for this AR.

 

[Nomo4me]

The max load I'm testing with Benchmark behind the SBK's is 23 grains. That's cutting .5 grain as allowance for the heavier LC brass from the load you show below.

23.5 grains of Benchmark with the 69 MK's loaded to mag length is a very good round in my AR, a good combo of accuracy and speed is still there, good out to 400 yards at least. Primers I use are the CCI BR-4's. My brass is Winchester so be careful with the LC brass.

Frank

 

[MGYSGT]

For me RE-15 was the ticket with Serria 69 gr. HPBT Match for targets. For PD's there was just too much elevation changes for that bullet. You know, a dog at 200 and the next one at 400 and the next one at 300. So I switched to a lighter bullet/Varget and more speed. It helped alot. I am sure RE-15 would have worked just as well as Varget with the lighter bullet.

Tom

 

[40X Guy]

The max load I'm testing with Benchmark behind the SBK's is 23 grains. That's cutting .5 grain as allowance for the heavier LC brass from the load you show below.

23.5 grains of Benchmark with the 69 MK's loaded to mag length is a very good round in my AR, a good combo of accuracy and speed is still there, good out to 400 yards at least. Primers I use are the CCI BR-4's. My brass is Winchester so be careful with the LC brass.

Frank

I like the Benchmark in my AR's, seems to be a clean powder and with 23.0 grains in your LC brass you should be very pleased. Keep us posted.

Frank

 

[markm87]

Our load, that seems to outshoot everything in a wide array of ARs is 69 gr SMKs, 22.9 gr H322, and Wolf SRM Primers.... A light factory crimp on the brass too.

I've never been able to hand load anything that comes close to the accuracy of this load. And this is blowing and going on a Dillon 550b.