I have been using ARCOMP but just tried CFE223. I am using a 55 grain FMJ boattail out of a 16" barrel. Hodgdon says the max load is 27.4 grains of powder but I went off of the advice of a few others on different forums and used 27.5 grains. Any idea on how it will effect it in practice?

My experience with CFE 223 is that the data Hodgdon has on its sight is a bit on the hot side for my AR. I switched from Varget with 69 gr Sierra MKHP. At 25 grns of CFE 223, I was getting the same velocity that they were with 25.8 grns.
You would be smart to work up your loads yourself and not put too much stock in internet advice, especially if that advice is to start at above what manufacturer's data recommends..

I went against their recommendation of 21gr max on a 62grn projectile.... after doing some research right at 25grn I got 2650fps out of an 11.8 .223wylde chambered upper.. im happy with that as 21gr only produced 2000fps

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This is the way....

A chronograph is one of the best investments any handloader will make.

When I was young I'd load Ruger and T/C handguns way above suggested max. Usually running H110/W296.

One of the first lessons the chronograph taught me was about saturation.

You can only burn so much powder down a tube, after that there's no gain in velocity. You're just shooting flames.

You may be able to reach max velocity with your particular combo at a much lower dose.

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GOA
USA Shooting Supporter

You need to look at the rifle the load data was from. At the Hodgdons site the test rifle has a 1in12 twist and a short throat.

My Savage .223 with a 1in9 twist has a longer throat than my AR15 rifles. And this rifle can be loaded "warmer" than short throated .223 rifles.



Many factory rifles today have longer chambers with enough room for the company lawyer to fit in also.

Below look at "N" freebore length, the 1in12 and 1in14 twist .223 rifles have a "short" .0250 throat length.