Early Merry Christmas to me, look what UPS dropped off from Sig Ammo at the ranch yesterday

Were the primers bulged?
I've got a 150 sst load with CFE BLK that runs 2300 out of an 18" upper that shoot great in cooler weather but i shot some this past weekend in 90* temps and i've got primer bulging. gonna have to step back and develop a warmer weather load that doesn't mess up primes

What resize die did you use for the 123gr and did it take very much pressure to resize them?

Lee 308 bullet sizer with Dillon Case lube highly recommend lubing the bullets before sizing makes a huge difference

I'd love to hear everyone's thoughts on the new Hornady 6mm ARC. From what I've read, it was designed to maximize the potential of the AR-15 platform. But I don't really see this as competition with the .300 HAM'R, but more of an optimized long range focused cousin. In essence both of these new calibers focused on squeezing more out of an AR-15. But whereas the 300 HAM'R has a larger and heavier bullet for increased penetration potential on tough game over shorter distances, the 6mm ARC, in contrast, optimizes longer range with a lighter bullet and different cartridge geometry.

I'm no ballistics expert, but I would love to hear from those who are about the trade offs. Of course, Bill, the HAM'R is your baby, but I see that Wilson Combat will also be producing 6 mm ARC components/rifles. So you would be the most versed as to how these two cartridges compare.

I love my two 300 HAM'Rs, but I'm wondering if I need to make space for a 6mm ARC in the collection.

I've spent most of a day for the past 4 days on the range doing 6mm ARC testing and load development. So far my observations are that this cartridge isn't anything special (basically a 6mm BR which has been around for a long time) and I was actually disappointed in how little velocity I was able to get out of the MAXIMUM charge weight loads Hornady provided me. The top velocity load with TAC pushed a 103gr ELD-X to 2521fps with so so accuracy, my most accurate load (consistent sub .8") with Benchmark only gives 2507fps. Considering I can get 2735fps from a 16" bbl (and stay under 57k psi) out of the Hornady 110gr SP in the HAM'R this didn't excite me much. However it made me want to do a head to head trajectory comparison, which ended up showing that out to any range where either cartridge still has much power their isn't much difference at all in how flat they shoot.

On the positive the test rifle ran 100% with all loads tested, has very mild recoil and is pretty quiet with a Quell suppressor. It just doesn't fit any need I personally have......kinda like the .224 Valkyrie a nice range toy.

Bill,

What load are you using to get 2735 out of the 110SP?

Thanks

All the lot #4 of CFEBLK I can stuff in the case and still seat the bullet to proper OAL. You can't get enough powder in the case to even reach 55k psi with this bullet. SOCOM is a more practical choice, but you can't reach 2735fps at a safe pressure, more like 2650fps out of a 16". The current lot #5 that's available is too bulky to reach top velocity with the 110gr

I've spent most of a day for the past 4 days on the range doing 6mm ARC testing and load development. So far my observations are that this cartridge isn't anything special (basically a 6mm BR which has been around for a long time) and I was actually disappointed in how little velocity I was able to get out of the MAXIMUM charge weight loads Hornady provided me. The top velocity load with TAC pushed a 103gr ELD-X to 2521fps with so so accuracy, my most accurate load (consistent sub .8") with Benchmark only gives 2507fps. Considering I can get 2735fps from a 16" bbl (and stay under 57k psi) out of the Hornady 110gr SP in the HAM'R this didn't excite me much. However it made me want to do a head to head trajectory comparison, which ended up showing that out to any range where either cartridge still has much power their isn't much difference at all in how flat they shoot.

On the positive the test rifle ran 100% with all loads tested, has very mild recoil and is pretty quiet with a Quell suppressor. It just doesn't fit any need I personally have......kinda like the .224 Valkyrie a nice range toy.