May I add my own suggestions? I’m a huge gun nut, I love to role-play, and I think more guns would allow for various different styles or themes of playing.
-Colt Python, 6 rounds .357 Magnum.
-S&W 586, 6 rounds .357 Magnum.
-Browning Hi-Power, 13 rounds 9x19mm.
-Beretta 92FS, 15 rounds 9x19mm.
-Kel-Tec PLR-16, 10 rounds .223.
-Luger P08, 8 rounds 9x19mm.
-Magnum Research BFR, 5 rounds .45-70 Gov’t. Actually means Big Frame Revolver, but has been misinterpreted as Biggest, Finest Revolver or Big Fucking Revolver.
-Desert Eagle .50 AE, 7 rounds .50 Action Express.
-Mauser C96, 10 rounds 7.62x25mm.
-Taurus Judge, 5 rounds .410.
-M1 Garand, 8 rounds .30-06. Very heavy (9.45 pounds IRL).
-Winchester Model 1894, 7 rounds .357 Magnum.
-Mauser Karabiner 98 Kurz, 5 rounds 7.92x57mm.
-Lee-Enfield No. 4 Mk. 1, 10 rounds .303.
-M1918 BAR, 20 rounds .30-06. Very heavy (18 pounds IRL. And that’s with an empty magazine and no bipod).
-M14, 20 rounds .308. Could potentially keep firing after the trigger is released in full-auto.
-M16A1, 20 rounds .223. Had a nasty reputation for jamming (when it’s implemented).
-IMI Galil, 35 rounds .223.
-AK-74, 30 rounds 5.45x39mm.
-AKS-74u, 30 rounds 5.45x39mm. Less accurate and much less power than a full-size AK-74.
-RPK, 40 rounds 7.62x39mm.
-H&K UMP40, 30 rounds .40. I notice a lack of .40 SMGs in the base game.
-M3 Grease Gun, 30 rounds .45.
-M1928 Thompson, 50 rounds .45. Looong reload.
-M1A1 Thompson, 30 rounds .45.
-Sten Mk. II, 32 rounds 9x19mm.
-MP-40, 32 rounds 9x19mm.
-Skorpion vz. 61, 20 rounds .32.
-Winchester Model 1887, 7 rounds 10-gauge.
-AA-12, 8 rounds 12-gauge.
-Kel-Tec KSG, 14 rounds 12-gauge.