Problems with .223AI max load testing for 80gr

[Tomekeuro85]

I've read a lot lately of people having good loads in their .223 AIs with 80gr amax... in the 25-26 gr range.





Took my rifle out today, loaded up incrementally from 24gr to 26gr.



Brass- PMC

Primer- CCI400

Bullet- 80gr AMAX seated to OAL 2.545"

Powder: Varget.

Indoor range temperature about 60f

24.0- Cratered

24.3- Cratered with light extractor marks

24.5- Cratered with more visible extractor marks

24.8- Pierced primer so I stopped.




Am I just missing something? Are various rifles really that different where some people can shoot 26gr varget as their go-to load and I can't even get to 25?




Anyone here using the 80s? Maybe someone more experienced than I can provide some helpful Info.

 

[BradY]

Use a primer with a harder cup. BR4 or 450.

 

[mac86951]

Use a primer with a harder cup. BR4 or 450.

+1 and what is distance to lands?

 

[Tomekeuro85]

I am .005 jammed.

I did the "have a snug neck and seat a bullet long and close the bolt on it" maneuver and got 2.540 maybe 5 times in a row. So I seated to have a slight jam.

 

[MrMajestic]

I understand GreTan does a real good job bushing firing pins.....
What's the H2O capacity of your case?

 

[IA_shooter]

Use a primer with a harder cup. BR4 or 450.

X2

If you are jammed and using the CCI 400 I can understand the early piercing. If you back off your seating just off the lands and use a harder cupped primer I think you'll get a little higher w/o problems.

 

[Tomekeuro85]

So from what I gather, I will load my next ones with cci 450's and maybe seat .005 jump.

At my next opportunity I will send GreTan my bolt for bushing the firing pin. Independent of this particular situation it's a nice thing to have anyways and not particularly expensive.


Do you think if I just seat them .01" deeper the problem may go away or at least improve?

 

[shoot4fun]

I had my bolt reworked to include an M16 style extractor and smaller firing pin hole. That cured my problems. I can get 2980 FPS with the 77SMK in a 22" barrel.

 

[Tomekeuro85]

Just an update:

Went back to the range with BR4 primers instead of the cci400s, as well as a .02" jump.


I got up to 26gr of varget with zero pressure signs. I will try further on my next trip out.

I'll find a good charge and then play with seating depth to fine tune.

 

[maxscm]

Get some Lapua Brass.

 

[flatlander]

I'd be interested in hearing from shooters who're loading the 80 Amax as to what sort of accuracy you're getting, relative to what you get with 75 Amax loads. I bought 1200 of the 80s a few years ago, but haven't found a load with them that shoots as well as just about any old load with the 75s. Had both 223 & AI on a couple of trued M700 actions with Krieger bbls - std 223 was 1-7.7tw, while the 223AI is a 1-7 - both were Rem varmint contour.