Lawfficer,
I looked up my loads for my Model 1 Sales upper. Not sure if these will work for you or not. Use at your own risk as you would anyones data. I have not had an opportunity to put these over a chrony but they are very mild.
My load is:
12.8 of H110
Remington benchrest primer
147gr FMJ (supplier says they are match bullets but ???)
R-P .223 brass or R-P .221 Fireball brass.
Brass Trimmed to 1.335
OAL 2.115 (bullets seated to about 1/2 way thru the cannure)
These have functioned fine in my AR, cycling it with 100% reliability. My rifle did come with an adjustable gas block and I beleive with this load it is pretty much open all the way. There are no high pressure signs and all the bullets exit the barrel
As I mentioned this is for information only use at your own risk.
I know some will notice I am trimming a little short and the OAL is less than you will find posted. My upper apparently has a tight chamber and shallow throat. I used posted trim lengths and OAL. Worked fine in my bolt gun but first one in my AR got jammed before going into battery. If you want a hair raising experience have this happen. Bolt carrier extended into the recoil spring tube so you can't seperate the upper and lower. Using the old pull on the charging handle and rap the butt end of the stock on the loading bench would not dislodge it. It was just a smidgeon short of locking up. I will NOT tell you how I got it into battery but surfice it to say it is NOT something for the faint of heart and I don't want to go over through it again any time soon.
At first I thought the upper had been mistreated or had a problem but it didn't. After going back to the basics I loaded some dummy rounds, should have done this first, after starting with brass shorted more than they needed to be. This improved the situation but still had some occassional sticking where the bolt would not open as it should. Then I started using trimmed brass with no bullets till I got a length that would allow the bolt to close with 100% reliability. Then I loaded some more dummy rounds with the bullet I was using and once again encountered occassonal issues with sticking. I varied the seating depth till I got 100% reliable cycling with no sticking.
So as it turns out I had two issues going on and needed to correct both. I have reloaded for nearly 25 yrs now but never ventured into the custom (wildcat) cartridge world prior to this. I am sure that what I went thru is amature stuff to seasoned wildcatters but after some search I have not been able to find anything that talks about working a round up from this very basic level. I didn't have any of these problems with my bolt gun, which I had before buying the AR upper. But this was a savage action and I headspace it to the sized round I was using and it had a fairly deep throat so that bullets seated to published OAL did not give me an issue.
I know this is little more information than Lawffice asked about loads but thought it might help some others avoid some of the pitfalls I had whether it be a .221/.300 Fireball (.300 whisper) or or a .458 Socom.
Thanks,
DonT