My Ruger SP101 2.25” (2019 manufacture) shoots 158 gr 38 Spl +P loadings high with its fixed sights. It shoots Remington 125 gr JHPs 38 Spl +P factory loads to its sights. Looks like Ruger has now calibrated its fixed sight revolvers to shoot lighter weight loadings. It is not much of a problem at very close range, but the difference is very noticeable at 50 ft and beyond. I enjoy shooting/plinking with my short barrel revolvers at longer ranges (ie beyond SD practice ranges) outdoors.

Appreciate any insight regarding SP101s and factory ammo weight bullets with their fixed sights.

Perhaps 357 Magnum 158 gr loadings will shoot to sights?

What you're describing is quite common. Heavier slower bullets will tend to hit higher than faster bullets. This I've been told is due to the slower bullet being in the barrel longer and more subject to the muzzle rise from recoil. One "cure" is to take up reloading. Then you can find an economical bullet/powder combination that hits right to the sights. My revolvers (with one exception) are all adjustable sights but I found it was handy to work up accurate loads for my semi auto's. This may not be practical if you don't get a chance to shoot very often. Handloading is often touted as being a way to save a lot of money. My experience though is that rather than saving a lot of money I'm just shooting a LOT more.

Been reloading for nearly 50 yrs. Always preferred the heavier 158 gr bullet...my standard +P handload which shoots high in the SP101 is 5.6 grs Power Pistol in either cast or swaged 158 gr SWC. Guess I’ll have to purchase some cast 125 gr bullets and try them. Conversely, I’m loading up some 158 gr SWC’s at 357 Magnum velocities which unfortunately is not an enjoyable load to shoot in these smaller revolvers.

Velocity is not as much of a factor as bullet weight.

You might try that "High" POA at 15-25 yard load , the next time you go shooting at 50 or 100 yards.

Even though it has a short barrel, that "High load" might settle down just right for a shot at a Jack rabbit out in our sage and desert lands, at the longer ranges.

I can shoot at Pigeons across the block on top of a telephone pole, with a 2.5x front sight hold with my Daisy BB gun.
The pellet hitting wood or feathers makes enough noise to scare them off, when waiting to get at my bird seed for the quail, doves and little birds.

Knowing how much or little of a front sight, comes in handy.....
plus a little Kentucky windage.

My old 2.5 inch SP-101 would shoot point of aim with 125gr Remington golden sabres and 135gr midrange handloads. I think most 158gr bullets don’t expand properly in a short barrel scenario

__________________
-Matt

...just ordered 500 125 gr cast RNFP bullets from Meister Bullets. Alliant Reloading has a 38 Spl Cowboy Action load with this exact bullet using 6.0 grs Unique (non +P according to Alliant’s site). Velocity of this load should duplicate +/- the velocity of Remington’s 38 Spl +P SJHP factory load (will test for that)