Hornady 123SST Load Data

[bboudie]

With all the posts about the 123 SSTs coming out I thought I would start a post on load data.

I have never done load development on a brand new bullet. I am fairly new to reloading but I am assuming loads close to the 123 AMAX would be a good reference point? I welcome your thoughts and suggestions on what loads to start with with. I use:

Lapua brass
CCI450s
CFE 223 and 8208 on hand but willing to try anything

Starting powder charge suggestions?

How far off the lands to start? Maybe the 129 SSTs is a good place to start with this question. I am just not sure.

I am excited about this new bullet. This should be a lot of fun.

[Bwild97]

Using CFE223 I would start at 31g and work toward 32.5g in .3g increments. Load 5 rounds of each weight. Measure the OAL for the 123g SST in your chamber and start at a seating depth that is about .010" from throat free bore (or the lands). Choose the best group per charge weight, and shoot a larger sample at varying distances to confirm accuracy.

[BLDtyLRY]

If you can afford QuickLoad software I recommend buying it. I've been running different scenarios and powders through QL and have narrowed my 123 SMK powder to AR-Comp. AR-Comp gives great load density and fps compared to 10x, 4198, 8208, Varget, H335 to name a few. If you provide me with COAL, barrel length, case capacity (h2o volume), bullet OAL and Min/max diameter of the boat tail and the length of the boattail; i could calc the predicted speed and pressures.

[BLDtyLRY]

Are you loading for a bolt action or AR? Loading to the lands may not be possible in an AR or bolt action if you are using a magazine; you are constrained by the mags max internal length

[bboudie]

BLDtyLRY:

Thanks for the replies. I am loading for an AR but from past experience it is a pretty tight chamber. I will look into getting QuickLoad. It sounds like a very useful tool. I am not sure if Hornady has posted the bullet specs on the new bullet yet though.

Take care and I may take you on your offer in the future.

[Bwild97]

Does QuickLoad have data for CFE223 and LeveRevolution yet?

[Dogue]

I know back in the 'old forum' days QL data wasn't ideal for the Grendel...not sure if that's changed or not.

[stokesrj]

Correct, Bill Alexander advised against using it because he had seen data that was dangerous and misleading.
Bob