RE: .45 ACP with 3" barrel
Curious why you are using the XTP. Are you loading a defensive load or something to target shoot or practice with? Very good but expensive target bullet.
I concur with the other posts and I would use factory ammo for defensive use since you may need to defend yourself in court after defending yourself on the street. My Colt Defender has 185 gr CorBons in it that kick out at 1060 fps in a 3" barrel. Plenty accurate for defensive work and hit hard. The mentioned Hydroshoks and SXT are also excellent factory loads.
I shoot a lot of 45ACP in competition. Lead bullets are cheapest but also dirtiest and smoke alot. Semi-Wad Cutters are great for scoring with clean holes in paper. Unless you have had your feed ramp polished, I wouldn' t necessarily recommend them. They can be finicky in some guns and need to be loaded just right.
Round nose or ball ammo is the easiest to load. It is generally more forgiving and nothing to hang up during the feed process. I load a 200 gr round nose moly coated Precision Bullet and it is very accurate and clean. For most loads, I use 5.5 grains of Winchester Super Light for around 900 fps but it is a discontinued powder so when I' m out, I have to switch. I will then use VV 320. It' s a clean and accurate powder, and it is excellent for 9mm that I also load a lot of.
Don' t necessarily load for the most velocity. Anything in the 850-900 fps range is plenty fast for a 200 gr bullet for most shooting. Your gun will take less of a beating too. Especially if it is an alloy frame.
I loaded the Defender with some very soft shooting loads for fun. These were the 200 gr precision bullet with 4.2 gr of WSL. It chronographed at around 560 fps and still functioned fine. It kicked less than a .380 Sig I had. Actually felt closer to my Ruger 22/45.
Get a Dillon Reloader and a case gauge to make sure your finished cases are sized right. And make sure you seat the primers flush. 45ACP seems to be more prone to misfires than other calibers if the primer is even a tad high. Then have fun.