ar-comp ladder question

[mdram]

i have been researching to develop a ladder for ar comp and 123gr sst
speer lists a 120gr with 25.3gr giving max pressure
quickload and grt agree with this

i see people posting 27gr loads or higher without pressure signs

i was thinking of a 10round ladder with .3gr increments
just wondering if 24gr was too high a start, or not high enough?
will be using new hornady brass with federal 205mar primers

edit: will be from an ar with 20" bartlein barrel, pf bolt, toolcraft carrier

[FRB6.5]

Might mention what you are going to be shooting it out of, the advice you get may vary based on that. You will get away with more in a bolt action.

[mdram]

updated post with firearm info

[JCSC]

I ran AR comp with 120 Gold Dot and went from 27-28.2 in .3 increments. CCI 450 primer, hornady twice fired at mag length.

20” gas gun. I had no pressure signs, but shot 1-1/2 groups across the ladders and never tried other bullets.

Not a lot of data out there. Start low and work up. YMMV

[grayfox]

Haven’t had my morning coffee yet so don’t recall where we got started with our loads on here, maybe do a search for the early threads. But all of my 123 class cup-core bullets I’ve found nodes around 27.8-28.2, 20-22” barrels. I think I started my ladders somewhere in the 26’s. I can’t speak to the Speer data, I’ve seen it and well, it just doesn’t fit with what I observe. Couple of other well known guys on here also do the 120 pro hunter around that load, iirc. I couldn’t really get the gold dots to shoot so don’t load them much, no offense to the bullet. At comp is my go to for the 123 sst.

[mdram]

hhhhmmm. maybe i will do one long ladder, .3 gr. single charge just to find the max pressure i can shoot safely
start @24 take it to 28 or 29

[grayfox]

Don’t go to 29. Plan on no more than 28.2-ish, watch mv and case/primers. Some can get to 28.4 but I would not set my sights on anything above that. 29 will be a waste, you’ll have to pull them.

[grayfox]

For a 20” barrel, the max you should see is somewhere low 2500’s, from 2475 to 2525. Don’t push it harder than that.

[mdram]

finally tested a ladder
i will do a .1 mini ladder in the yellow area[ATTACH=CONFIG]17361[/ATTACH]

[JTB]

I load 27.6 AR Comp at 2.260. I started at 26.4 and worked in .3 increments to 28.0. 22” barrel 1/8 twist. I need to work it up again. I added a comp and my groups opened up a little. 123g ELD

[gldprimr]

FWIW - I worked up to 28.0 gr. AR-Comp with 125 gr. Nosler Partition getting 2550 fps out of 24” barrel CZ-527.
That was where velocity leveled off for me. I went past that to 28.2 gr. & 28.4 gr. - no velocity increase so I kept it to 28.0.

[Chance-dg]

I too am trying to get to 2450 or 2500 with AR Comp and either 120g Gold Dots or 123g ELD Ms 27.6g I think is my stopping point as accuracy fell off and ejector swipes became noticeable on new Hornady brass and CCI 450 primers

[Chance-dg]

Gas guns 18" Wilson Combat and 16" Group buy barrels.