Greetings all, I am a new Glock 29SF owner. When I picked up my new Glock the store owner threw in a couple of boxes of 180grn AE High Antimony Lead target ammo. I'm not a fan of firing unjacketed ammo through my semi autos and was wondering if anyone has experience with this type of target ammo. I've never heard of "high antimony" lead ammo before and don't want to foul the barrel of my new pistol.

Trail runner, Welcome to the forum
Apparently this is older Federal cast bullet offering they must have had in their inventory.  You could use them but be sure to inspect and clean after a range secession.  In term of cast bullets the higher antimony makes the lead slightly harder than pure lead and the bullet can take the higher pressure.

Now that being said, one of the things about cast bullets id the can leave lead deposits in your bore.  How can this be eliminated?  Bullet size is the main key factor...usually bullet 0.001" to 0.002" over the actual bore diameter are needed.  Glock factory bores usually need 0.002" in the 10mm and 40S&W guns.

Seeing you are new to Glocks, you will read that Glock doesn't recommend any lead bullets in their guns.  Well there are many people who do shoot cast bullets from their factory barrels, me included.  Being a bullet caster I use them often.
For my 10mm Glocks & all my 10mm & 40S&W guns, I size my bullets a at 0.4015" and use a good quality lube on the bullet.

This has prevented leading in my bores, but I also clean and inspect after a range secession.  We did a pull-down some time back on a Federal 180 grain (older) this may have been from the Federal American Eagle High Antimony Lead target ammo back in the day...

BTW Federal is also starting to offer ammo with the poly powdered paint coatings, where these baked on finishes serve as lube and eliminates the lead from contacting the barrel.  the finish is very tough.

Wow, great info, thanks. I guess I'll save these for a "rainy day" and buy some jacketed target ammo.

Your welcome I added a little bit more info while you responded so read it again for the added info.

I haven't seen any of that stuff in years. I would at least try them in your pistol, a few rounds, check for leading. My 20 hates conventional cast bullets but dotes on powdercoated bullets.