Iron sights --adjustable sight or no adjustable sight?

What do you guys like in iron sights?

My opinion, non adjustable iron sights are useless on anything other than a defensive gun for what I'm interested in.

Scott

I would think adjustable sights are a must. Occasionally I find that I have to make a one or two click change, even though it's the same pistol and same ammo, every now and then it needs tweeked. Maybe it's a slight change in my grip, or lighting, or maybe just me, but a change is required. Side note, I shot next to, scored for a guy at a match a couple years ago that was using a Ruger MkII with fixed sights. It was his first match ever. He actually had some real nice groups on paper, most shots would have been in the black, but they weren't because they were all at 7:00 to 8:00 on the edge of the black. I suggested he move his sights, then he told me he couldn't, they were fixed. He just continued on shooting like he was. When it was over I asked him if he enjoyed it. The smile on his face was more than enough of an answer. I hope he gets adjustable sights, he would actually be a pretty good shot.

IMHO, adjustable sights are mandatory for this sport.  There's always a sight change between 50 and 25 yards.  When you start trying different loads, you'll usually need to adjust sights, especially if your reloading your own ammo.  Most of us reload.

Aristocrat

I guess it depends on how "fixed" those fixed sights really are. Are we including "fixed" sights set in a dovetail (be it the front and/or rear)?
Also, the quality of sight picture comes into play. The old King "fixed" 1911 Hardball sights offered an excellent sight picture.
A lot of folks talk about enjoying the challenge of shooting a 1911...there was a time when you had shoot an "as -issued" 1911 with original sights and issued service ammo.

But speaking of service pistols:
As of April 1st, the CMP has added to their approved Service Pistol list the S&W model 10 and model 15.
The SA trigger weight limit is lower for the revolver. Personally, in that circumstance I'd take a S&W model 10 over most of the "fantastic plastic" found elsewhere on the list.

For Int'l Muzzleloading Pistol matches you have to shoot exact period sights. Usually those are fixed and small, with tapered front post sights and V notch rear.
Yet, some folks manage to shoot great scores!

Jim

I would say adjustable iron sights are preferred. However, if your pistol came with non adjustable, usually windage only sights, there are workarounds to making them precise. Drift for windage, file front or rear for vertical alignment. Though even when perfectly adjusted you will always be limited. Different ammo can have different ballistic profiles that you will not be able to adjust for. Some days your body will want to shoot and group differently even with same ammo. Now if not at the match then I would say it's good to know and try to fix these body errors. But at the match you want to fix sights )). However, even though I have red dot on my pistols I prefer to shoot irons for the reason that you do not chase the dot, feel less wobble and release your shots faster and cleaner.  I admit I hate chasing the dot ))

I re-read your question and want to add on iron sights:
-adjustable vertically and horizontally, in best case also aperture/opening width.
-front sight - perfectly machined to be a perfect rectangle, no leaning to either side. Not too thick, just thick enough to pick up easy, but at the same time thin enough to center target. Seems that euro guns like their sights thick, I do not like that. Also I prefer my front sight flat black, no beads, fiber, etc. In bullseye you do not need to acquire sight super fast, but flat black will allow you to pick up sight precisely.
-rear - perfect square or rectangle opening with no tilts. No u-notch, no dots. Just my preference. Some but minimal space between front and rear sights when acquired, this way easy to see if centered properly - this becomes less needed once you ger more profficient. It will be more and all about front sight picture, so make sure it is right width and perfectly machined.

I'm a complete noob to bullseye pistol. What's a common elevation adjustment with irons between 25 and 50 yards?

Great Question!
It depends on the cartridge and load.
22, 38, and 45 will all be different.
My first CF was a WWI era S&W 2nd model Hand Ejector in its original 455 chambering., and original fixed sights.
I used two different weight cast bullets for 50 and 25 yds to keep point of impact fairly close.

Some guys will use Nosler 45 JHPs for 50 yds and cast SWCs for 25 yds without changing sight settings.

Depends on ballistics of what you are shooting. See below link as a visual reresentation, elevation adjustment would be drop in inches into MOA conversin, then into how many MOA is each click on the iron sight as per manufacturer specification (usually 1 click= 1 MOA). So at 25 yards 1 click would be 1/4 inch change in impact, at 50 yards 1/2 inch. Most of us guesstimate and test as a part of sighting in.  Shoot target, then adjust as necessary, remember total adjustment for a specific load. 

https://www.mcarbo.com/9mm-trajectory-chart-vs-40-s-w-trajectory-chart.aspx

Understanding MOA:
https://www.nssf.org/shooting/minute-angle-moa/
https://www.google.com/amp/s/nwsportsmanmag.com/how-to-understand-minute-of-angle/amp/