223 55gr FMJ Powder charge?

[JimT]

I was at the range on Saturday checking load accuracy in my AR 15 with a 1-9 twist, I had LC 55gr and 62gr factory ammo, both, did not shoot too well. I had some Arnold Ammo 223 55gr reloads I bought a few years ago and figured what the heck I will put it on paper, Well to my surprise it shot pretty decent groups and with different head stamped brass. When I got home I pulled some bullets and weighed the charge, it was 27.5 gr exactly, it looked like H335, but I checked the data and there was no weight charge with that much H335 powder, or any other granulated powder that I could see. Does anyone know about Arnold Ammo? I bought a 1000rnds from Patriot Pawn. Also any help what the powder might be? Maybe BLC2?
                                                           Thanks Jim

[J Mack]

Anything is possible with Arnolds Ammo good or bad (Read I’ve seen some really hot unsafe ammo in their boxes) so it’s not unrealistic to think you have 27.5 gr of H335. If I had to guess I would say they used some of the pull power that was readily available at the time you bought your ammo WC844 that’s very similar to H335 and like all pull powder WC844 has different burn rates from batch to batch so 27.5 could very well be a safe load.
Good luck!

[Jaggy13]

I've loaded up to 26.5 with 844 and had velocities around 3100fps.
Like Jmack said, could be right in there. I've shot several different batches now and haven't ever needed to go that high of a charge again. My current load is 25grn.

[Birddog6424]

Good luck!

Slang for, "Hope you don't get blown up".

[J Mack]

Slang for, "Hope you don't get blown up".

It was more of just a good luck wish for a new member asking for advice.

I will add that as a precaution it might not be a bad idea to shoot a few rounds through a chronograph to get an idea of the velocity with your Arnold’s Ammo, like Jaggy said I too load with WC844 and never approached 27.5gr of powder and I typically hover around 24/25 gr of powder with a 55 gr bullet and shoot for that 2800/2900 FPS range.

With that said I’ve seen data that indicates M193 was loaded with up to 28.5 gr of WC844 and had velocities of 3250 FPS but that is new 5.56 ammo, I started to get extreme pressure signs around 27gr and back down to that 24/25 range. Your biggest problem with the Arnold’s Ammo will come from improperly head spaced cases combined with the hot charges of powder. Most of the bulk brass available for reloaders comes from ranges were the rifles shooting the cartridges have worn out chambers like military and police and the head space on the brass has moved a significant amount, to speed up the process some reloaders will under size all brass to compensate for the extremely long ones and trim to length netting a short head spaced cartridge with thin web, if loaded to max or beyond this scenario will net case head separation and would be the unsafe ammo I was in reference to.             

Some data for WC844: https://www.americanreloading.com/img/AmericanReloadingWC844-5.56NATODATA.pdf