Hi Mike,
Congratulations on your 27-2. You'll love the 27. I addition to the 5", I also have a 6" that was made a year earlier. Both are great shooters with lead or jacketed bullets.
Both of my 27s are blued and have grooved service triggers, checkered semi-target hammers, and checkered topstraps. The 5" has a plain ramped front sight whereas the 6" has a plain partridge front sight. Rear sights on both are adjustable with plain blades.
The target hammer, target trigger, red ramp front sight, and white outline rear sight blade did not become standard on the 27 until 1976 or thereabout.
For a relatively light, but extremely accurate load, I use 6.0 to 6.5g of Universal Clays with the 158g Oregon Trail Laser-Cast LSWC in a magnum case. Very clean burning load with no leading.
I look forward to hearing about your new 27.
Bob