Most jacketed bullets are .451. You might check again, and measure some other bullets as well.
Bullseye is fine for .45, but will have sharper recoil at max loads than some slightly slower fast powders, and especially medium burn speed powders like Unique.
Speer Manual recommendations of 5.7gr Bullseye with 1.26 COL
That is the Speer #13's MAX load. Sounds like you just went straight for the max, which is not safe reloading practice, especially for a beginner.
I would recommend that you go back, start at 5.2, which is the Speer #13's start load, and see how you like that. Then you can work up .1 Gr at a time until it shoots well and the recoil is what you want.
If that does not get you what you want, you might try a slower powder next time. W-231 would be a good choice.
If you are looking for a soft target/plinking load, you may want to try some lead bullets with still lighter charges of fast powder like Bullseye, Clays, etc.
Lead is much cheaper, and any sane load with any quality cast bullets will not lead in .45 ACP.
Brad from
Missouri Bullets participates here at THR, and he and his bullets are getting a great deal of positive feedback.
There are, of course, many places to get quality cast bullets.
Welcome to
THR