First off, apologies for what will be a long description.

Just got a hold of Quickload, and wanted to run it on a recipe I've been using for my .308 - but had a question.  I'm using MKE 7.62x51 brass , which is supposed to be military spec, that is resized to .308 Win.  So when I enter data in Quickload, do I choose the option for ".308 Win (CIP)" or ".308 Win SAAMI"?

The load is towards the hot end of things.  I'm not really seeing pressure signs on the brass, but am slightly concerned since it's on the upper end of the load.  I worked my way up from 39.0gr in 0.5gr increments.  Here are the specs of the reloads:

MKE 7.62x51 sized to .308 Win - 1.620 on my Hornady comparator (my chamber is measuring at 1.622), water volume is 55.5gr (resized).

Brass trimmed to 2.005"

Hornady 168gr Match HPBT, loaded to 2.800" COAL (I'm seating base to ogive at 2.185", which gives COAL of ~2.800")

IMR4895, 41.5 gr (0.1gr above max using Hornady .308 Service rifle data, Hornady Book 9th Edition.  Max load using regular .308 Win data is 43.3gr)

Winchester Standard Large Rifle Primers

Load chronographs to 2440 fps (either Quickload option predicts around this - 2412 for either option)

Rifle is a Marlin X7VH bolt action, 18: Heavy Barrel with 1:12 twist

On Quickload, entering the above  data for .308 Win (CIP) gives me a pressure of 46126psi, slightly above the MAP-25% value.  If I use the .308 SAAMI option, I get a pressure of 46126, slightly below MAP-25%.

I get good accuracy from the load, and am not seeing ejection marks, nothing on the bolt face, easy to extract, primers look OK.  But for completeness sake, I kind of want to know which option to use on Quickload (both for this and for evaluating other loads in the future).

Not sure if you intended it, but they both show the same pressure?   If memory holds, MKE is heavier brass, and I use smaller charges in it then Win brass.  The velocity looks on the safer end for a 18 inch barreled bolt action and your powder.  Am guessing Hdy's service rifle section is for the M1A, which a lot of people download compared to bolt actions.

.308 and 7.62x51mm are the same, the real difference is the military uses the copper crusher method to test pressure. SAAMI/CIP uses PSI via the transducer method.

7.62x51mm brass must be downloaded 2.0 whole grains of powder. The average 7.62x51mm case weighs around 180 grains empty and unprimed. Winchester brand commercial brass weighs closer to 155 grains empty and unprimed. Huge difference.

I consider 40.5 grains of IMR-4895 as a maximum load with 168's. Primer selection makes a difference as to how much powder you can use. You're definitely at or over maximum.

Work your load downward in .5 grain increments to see if accuracy improves. 39.5 to 40.5 should all provide decent accuracy and be easier on your brass and rifle.

That's one of the things that was messing me up.  I enter the identical data for the CIP and SAAMI options, they give me the same velocity - but on the curves, the CIP curve is just above the MAP-25% threshold, the SAAMI curve is just below it - so I'm unsure which to go by.  Either way, I'm toeing the line I guess.

I weighed the MKEs (unprimed).  Around 170gr.  I'll probably go back and try some lower charges again - which will kind of suck, as I get really good results from this load - but am a little leery, as I know it's definitely up there in terms of charge.

I'm somewhat happy though that using Quickload confirms some of the load work up - as the velocity I am getting is damn close to what they predict.  So while I'm toeing the line at max,  and giving the brass a workout - I'd like to be able to infer from it that I'm still within reasonably safe parameters.  Already knowing I was at/near max, I was kind of expecting it to give me a lower velocity that what I was actually seeing.  Still worth it to chase back down a little though, I think.

In QuickLoad, you're supposed to be using the water capacity of a fired in your chamber case, not the sized volume.  You'll have a smaller volume available for the hot gas with the resized case and that will show higher pressure than if you use your actual chamber capacity.

The fired case volume will vary between commercial vs military brass which is why you're supposed to start 2 grains lower charge.

When you are figuring case capacity, the length of the brass will also matter to a degree.  If I just did the math correctly, assuming a .310" inside neck diameter after firing, each .010" difference in neck length will make about 0.2 grains of capacity difference given that the case bodies and shoulders are exactly the same.  (Water weighs .03606 pounds per cubic inch according to google and then using the formula for the volume of a cylinder and 7000 grains in a pound.)

I went back into an old spreadsheet when I was playing with different head stamps of brass.  In MY chamber, I had the following case capacities:
PMJ brass with case weights 179.8 grains or less: 55.06 grains h2o capacity
PMJ brass with case weights between 179.9-180.9 grains: 55.07 grains h2o capacity
PMJ brass with case weights between 181.0-182.0 grains: 54.9 grains h2o capacity
PMJ brass with case weights over 182.0 grains: 54.8 grains h2o capacity
LC-11 LR: 55.07 grains h2o capacity
WCC-10: 55.5 grains h2o capacity
StarLine - but in a different barrel/chamber: 55.46 grains h2o capacity

The other big change in case capacity will be seating depth assuming the same bullets.  QL uses the empty case capacity - volume taken up by the bullet inside the case for its initial capacity used for pressure calculations.  Until the bullet gets close to the lands, it's a fair approximation.

Once you get the bullet close to the lands, change the shot start pressure from 3626 psi to 10,826 and watch what happens.

With all that said, if the commercial and military brass have the same volume after firing, I'd think you'd be OK to use the same charge weight in both types of cases.  But I wouldn't make that assumption until I had my fired case volumes to model, and I'd get those volumes using 2 grains less powder in military brass than the commercial.