Precision .223 AR15 load dev., is it worth to do seating depth testing?

[tstanek]

Hi guys,
I'd like to ask you about your opinion and thoughts on aforementioned topic. Im currently developing a load for my Schmeisser AR15, 223 Rem., 18' heavy barrel 1:9 twist for "precision semi auto shooting" up to 300 metres (app. 330 y). I'm currently at the stage of being almost satisfied with it, but still want to tweak it a bit. I use Lapua brass, CCI BR4 primers, RS 40 (Reload Swiss) powder and SMK's 77 Grs. Just very brief summary of reloadinng process - flame annealer, FL size with Redding bushing die, Wilson exp. mandrel, trim, chamf.,...powdering with lab scale and seating with normal RCBS seater + a slight crimp with the same die as used for seating. I'm currently on 22,7 Grs of powder load, with COAL at 2,25 (which is my safe mag limit) and being able to shoot the groups as on the pic at 110 yards repeatedly. Would you try to go further and some seating d. testing? Im not sure if it's worth to spend components as it is an AR15 still...meaning the limits of gun's accuracy etc. Thanks in advance for any comments and have a nice Sunday!

 

[jLorenzo]

I'm facing the same thing. I think its worth doing if you want to continue to try and improve your load. You can only really move back from mag length. I would think in a quality barrel with quality components you may find improvements. I have found the Hordnady 75gr bthp to actually shoot better once moved back from max mag length, althouhg I'm not entirely happy with that bullets performance overall. I have moved to Sierras for accuracy load and am currently playing with seating depth also. Running out of powder and having to switch to a different kind hasn't helped my progress though.

If it was me I would be more than happy with your group especially if its reasonably consistent. Depends how the intended target size also.

 

[FALex]

Without knowing about your powder, and how much case capacity is left, being limited by your mag length, and using 77gr bullets, I would not mess with seating depth. TBH, even if you were running 69gr, I would have the same opinion.

I'm sure some have obtained improved results by getting the bullet further into the case, but I don't think it is many. If your rifle is putting together groups like the one posted, I would not worry about it. That's a damn fine group.

If I messed with anything, it would be the neck tension, but again, it's looking very good already.

 

[jLorenzo]

Hi guys,
I'd like to ask you about your opinion and thoughts on aforementioned topic. Im currently developing a load for my Schmeisser AR15, 223 Rem., 18' heavy barrel 1:9 twist for "precision semi auto shooting" up to 300 metres (app. 330 y). I'm currently at the stage of being almost satisfied with it, but still want to tweak it a bit. I use Lapua brass, CCI BR4 primers, RS 40 (Reload Swiss) powder and SMK's 77 Grs. Just very brief summary of reloadinng process - flame annealer, FL size with Redding bushing die, Wilson exp. mandrel, trim, chamf.,...powdering with lab scale and seating with normal RCBS seater + a slight crimp with the same die as used for seating. I'm currently on 22,7 Grs of powder load, with COAL at 2,25 (which is my safe mag limit) and being able to shoot the groups as on the pic at 110 yards repeatedly. Would you try to go further and some seating d. testing? Im not sure if it's worth to spend components as it is an AR15 still...meaning the limits of gun's accuracy etc. Thanks in advance for any comments and have a nice Sunday!

What are you doing as far as brass prep? Anything in particular that got your groups to tighten up like the one you posted?

 

[tstanek]

What are you doing as far as brass prep? Anything in particular that got your groups to tighten up like the one you posted?

I decap the brass, then flame anneal with torch flame and AGS annealer -> FL resizing Redding S FL die with .247 bushing -> run with Wilson exp. mandrel. After that trim if needed and chamfer + deburr every time ending with dry tumbling in corn for an hour or so. I don't clean primer pockets when preparing 223 brass. I have RCBS rock chucker press

 

[db2000]

Interested to see groups at 300m and beyond.
1:9 isn’t typically thought of as ideal for 77 gr but I also haven’t read a lot of real world experiences with it. Also, I assume same manufacture for all the brass? 10 shot group would be a nice test as well. Just my $0.02
Random brass x 1 firing and processed back to spec. 205M primer. 23.8 gr H4895 16” Proof barrel.

 

[jLorenzo]

I decap the brass, then flame anneal with torch flame and AGS annealer -> FL resizing Redding S FL die with .247 bushing -> run with Wilson exp. mandrel. After that trim if needed and chamfer + deburr every time ending with dry tumbling in corn for an hour or so. I don't clean primer pockets when preparing 223 brass. I have RCBS rock chucker press

Out of all that did you notice one thing affect group size more? Probably the right bushing and mandrel?

 

[Seymour Fish]

Hi guys,
I'd like to ask you about your opinion and thoughts on aforementioned topic. Im currently developing a load for my Schmeisser AR15, 223 Rem., 18' heavy barrel 1:9 twist for "precision semi auto shooting" up to 300 metres (app. 330 y). I'm currently at the stage of being almost satisfied with it, but still want to tweak it a bit. I use Lapua brass, CCI BR4 primers, RS 40 (Reload Swiss) powder and SMK's 77 Grs. Just very brief summary of reloadinng process - flame annealer, FL size with Redding bushing die, Wilson exp. mandrel, trim, chamf.,...powdering with lab scale and seating with normal RCBS seater + a slight crimp with the same die as used for seating. I'm currently on 22,7 Grs of powder load, with COAL at 2,25 (which is my safe mag limit) and being able to shoot the groups as on the pic at 110 yards repeatedly. Would you try to go further and some seating d. testing? Im not sure if it's worth to spend components as it is an AR15 still...meaning the limits of gun's accuracy etc. Thanks in advance for any comments and have a nice Sunday!

Leave pal as is and get rid of crimp

 

[Seymour Fish]

Leave pal as is and get rid of crimp

O A L (dammit)

 

[supercorndogs]

For 330 I would shoot 50,55, 0r 60g in 223, what ever I can find cheap. They work fine out to 600y if the wind isn't blowing much. On a gusty day 600y can be frustrating.

 

[912173]

Check out the cmp forums. The service rifle guys have tons of load discussion. One of the go to loads is lake city brass and 23-24gr Varget with a 77 gr smk or nosler with cci 450 primers. They really don't overthink load development as they want trigger time and wind reading practice instead of fiddling with loads. The 77 smk and nosler are very forgiving with seating depth. If the 77s stabilize then run them but 69 smks might be required.

 

[Snuby642]

I'll just add nice group.