These must be the most forgiving firearm ever made. I reload mine with Hornady .310 123 gr bullets, but I have also loaded it with various .308 bullets. The 125 gr Speer TNT's are excellent, also the 150 gr balistic tips. I have also had a lot of fun with 200 gr pointed cast bullets. This was a special run mold from Lee and can be used with gas-checks. I could probably go above 2000 fps with them, but I have more fun with 4.0 grs of Red Dot. Great Back Yard Thumper loads, very quiet but plenty of knock-down power.