Let me start by saying I am completely new to reloading.
My step dad recently bought me a Hornady LocknLoad kit to start reloading. Ive reloaded with him only a few times and I plan to study and learn as much as I can before I get started. I'm building my bench now and getting everything lined out to get started.

I'm currently thinking a lot about my initial load work up.
I'm going to be shooting 105gr Amax bullets threw a Rem 700 SPS Varmint in .243.

A friend on mine loaded up the following load for me that shot 1/2" groups at 100yrds.

105gr amax
42.5gr of IMR 4350
Federal 210M primers
Seated at 2.800 COAL

The COAL is longer than all my reloading books state. Is this too long? Feeds well and shoots well I just want to be safe.

I'm curious since this load shot so well that I should just duplicate it. But reloading manuals I have looked at recently say that this is too high of a charge weight and its exceeded max pressure by 6000lbs. (66,000lbs)

Is this a safe load to start with?

Should I start at 38gr and work up to it in .5gr increments?

The fired brass show a slightly cratered primer where the firing pin hits it, but the edges of the primer are not flattened. I will add pics of the fired brass soon. Is this a sign or too much pressure or is it just because the Rem 700 firing pin hole is larger than the firing pin?

Any advice would be greatly appreciated.
Please advise if any information needed to answer my questions is not provided above.

Thanks,

Ryan

Until you get your feet firmly on the reloading ground I certainly wouldn't be doing any experimenting outside of the safe limits of a good load book. As far as shooting a "buddy's" cartridges that are known to be hot, I wouldn't do that if it was my mother.
I'd suggest getting a good load book and reading it through and through before you go further.

ALWAYS!!!!!!!!!

Start low and work your way UP!

We need more "handloaders". Blow ups make the rest of us look bad!

And you'd feel terrible if while maiming yourself your "blowup" hurt surrounding shooters.

.

My 2 Rem sps 243's would not stabilize the 105. But every beast is differant. shayne

It shouldn't be a problem if its not hot and in the lands.