From what I can find, the F6 carried 6 M3's.  
 
 
The PV-2 also had some M3's in one of the variants.
Still diggin for info. 
 
 
EDIT:
found this table..
http://www.geocities.com/CapeCanaveral/ ... un-ta.html
Name	First
Delivery	Country	Weight
of Fire	Muzzle
Power	Armament
Boeing P-26A 	34 Jan 	USA 	0.39 	140	2 * 7.62 mm Browning .30 M2
Arado Ar 68F-1 	36 Feb 	Germany 	0.37 	110	2 * 7.92 mm MG 17 (500)
Supermarine Spitfire Mk.I 	36 Jun 	Britain 	1.72 	480	8 * 7.7 mm Browning .303
Macchi C.200 Saetta 	36 Jul 	Italy 	0.86 	250	2 * 12.7 mm Breda-SAFAT
Hawker Hurricane Mk.I 	37 Oct 	Britain 	1.72 	480	8 * 7.7 mm Browning .303
Messerschmitt Bf 109C-1 	38 Feb 	Germany 	0.73 	110	4 * 7.92 mm MG 17
Nakajima Ki.27-Otsu 	38 Mar 	Japan (A) 	0.32 	90	2 * 7.7 mm Type 89 (500)
Curtiss P-36A Hawk 	38 Apr 	USA 	0.80 	300	1 * 12.7 mm Browning .50 M2,
1 * 7.62 mm Browning .30
Fiat G.50 Freccia 	38 Oct 	Italy 	0.86 	250	2 * 12.7 mm Breda-SAFAT
Messerschmitt Bf 109E-3 	38 Late 	Germany 	2.37 	530	2 * 20 mm MG-FF,
2 * 7.92 mm MG 17
Polikarpov I-153 	39 Feb 	USSR 	1.43 	480	4 * 7.62 mm ShKAS
Fiat CR.42 Falco 	39 Apr 	Italy 	0.86 	250	2 * 12.7 mm Breda-SAFAT
Bloch MB.152 	39 Apr 	France 	3.26 	1230	2 * 20 mm Hispano 404,
2 * 7.5 mm MAC 1934
Caudron C.714 Cyclone 	39 Jun 	France 	0.50 	140	4 * 7.5 mm MAC 1934
Grumman F4F-3 Wildcat 	40 Feb 	USA 	2.43 	920	4 * 12.7 mm Browning .50 M2
Messerschmitt Bf 109E-4 	40 May 	Germany 	2.37 	530	2 * 20 mm MG-FF,
2 * 7.92 mm MG 17
Nakajima Ki.43-I-Otsu 	40 Jun 	Japan (A) 	0.73 	225	1 * 12.7 mm Ho-103 (250),
1 * 7.7 mm Type 89 (500)
Mitsubishi A6M2 Reisen 	40 Jul 	Japan (N) 	2.62 	410	2 * 20 mm Type 99-1 (100),
2 * 7.7 mm Type 97
Bristol Beaufighter Mk.IF 	40 Jul 	Britain 	7.35 	2370	4 * 20 mm Hispano Mk.II,
6 * 7.7 mm Browning .303
Messerschmitt Bf 109F-1 	40 Nov 	Germany 	1.04 	420	1 * 15 mm MG 151,
2 * 7.92 mm MG 17
Mikoyan-Gurevich MiG-3 	40 Dec 	USSR 	1.55 	545	1 * 12.7 mm UB,
2 * 7.62 mm ShKAS
Bell P-39D 	41 Feb 	USA 	3.02 	860	1 * 37 mm M4,
2 * 7.62 mm Browning .30,
2 * 12.7 mm Browning .50 M2
Lavochkin LaGG-3 	41 Feb 	USSR 	1.99 	710	1 * 20 mm ShVAK,
2 * 7.62 mm ShKAS
Supermarine Spitfire Mk.VB 	41 Mar 	Britain 	2.24 	1250	2 * 20 mm Hispano Mk.II,
4 * 7.7 mm Browning .303
Curtiss P-40D 	41 May 	USA 	2.43 	910	4 * 12.7 mm Browning .50 M2
Hawker Typhoon Mk.IB 	41 May 	Britain 	5.20 	2010	4 * 20 mm Hispano Mk.II
Focke-Wulf Fw 190A-3 	41 Mid 	Germany 	5.20 	1210	2 * 20 mm MG 151/20,
2 * 20 mm MG-FF,
2 * 7.92 mm MG17
Nakajima Ki.43-I-Hei Hayabusa 	41 Jun 	Japan (A) 	1.14 	360	2 * 12.7 mm Ho-103
Macchi C.202 Folgore 	41 Jul 	Italy 	1.13 	320	2 * 12.7 mm Breda-SAFAT,
2 * 7.7 mm Breda-SAFAT
Yakovlev Yak-1 	41 Dec 	USSR 	1.99 	715	1 * 20 mm ShVAK,
2 * 7.62 mm ShKAS
Yakovlev Yak-7 	41 Late 	USSR 	2.64 	1080	1 * 20 mm ShVAK,
2 * 12.7 mm UBS
Brewster F2A-3 Buffalo 	41 Late 	USA 	2.43 	920	4 * 12.7 mm Browning .50 M2
Messerschmitt Bf 109F-4 	42 Early	Germany 	1.64 	470	1 * 20 mm MG 151/20
2 * 7.92 mm MG 17
Kawasaki Ki.45-KAI-Ko 	42 Jan 	Japan 	2.07 	680	2 * 12.7 mm Ho-103,
1 * 20 mm Ho-3 (100)
Nakajima Ki.44-I-Ko 	42 Jan 	Japan (A) 	2.28 	720	4 * 12.7 mm Ho-103 (250)
North American Mustang Mk.I 	42 Feb 	USA 	1.99 	730	2 * 12.7 mm Browning .50 M2,
4 * 7.62 mm Browning .30
Republic P-47B Thunderbolt 	42 Mar 	USA 	4.85 	1830	8 * 12.7 mm Browning .50 M2
Vought F4U-1 Corsair 	42 Jun 	USA 	3.64 	1370	6 * 12.7 mm Browning .50 M2
Kawasaki Ki.61-I-Otsu 	42 Mid 	Japan 	2.28 	720	4 * 12.7 mm Ho-103
Messerschmitt Bf 109G-5 	42 Mid 	Germany 	2.32 	640	1 * 20 mm MG 151/20,
2 * 13 mm MG 131
Supermarine Spitfire Mk.IX 	42 Jul 	Britain 	2.24 	1250	2 * 20 mm Hispano Mk.II,
4 * 7.7 mm Browning .303
Messerschmitt Bf 109G-6 	42 Aug 	Germany 	2.46 	640	1 * 20 mm MG 151/20,
2 * 13 mm MG 131
Mitsubishi A6M3 Reisen 	42 Aug 	Japan (N) 	2.48 	520	2 * 20 mm Type 99-2 (125),
2 * 7.7 mm Type 97
Lavochkin La-5 	42 Sep 	USSR 	2.56 	950	2 * 20 mm ShVAK
Macchi C.205V Veltro 	42 Sep 	Italy 	3.69 	970	2 * 20 mm MG 151/20,
2 * 12.7 mm Breda-SAFAT
Lockheed P-38F Lightning 	42 Sep 	USA 	3.73 	1420	1 * 20 mm Hispano,
4 * 12.7 mm Browning .50 M2
Grumman F6F-3 Hellcat 	42 Oct 	USA 	3.64 	1370	6 * 12.7 mm Browning .50 M2
Nakajima Ki.43-II-Ko 	42 Nov 	Japan (A) 	1.14 	360	2 * 12.7 mm Ho-103 (250)
Yakovlev Yak-9 	42 Nov 	USSR 	1.92 	780	1 * 20 mm ShVAK,
1 * 12.7 mm UBS
Messerschmitt Me 410A-1/U2 	42 Dec 	Germany 	3.29 	950	2 * 20 mm MG 151/20 (350),
4 * 7.92 mm MG 17 (1000)
Nakajima Ki.44-II-Otsu 	42 Late 	Japan (A) 	2.28 	720	4 * 12.7 mm Ho-103 (250)
North American P-51B Mustang 	43 Early	USA 	3.64 	1370	6 * 12.7 mm Browning .50 M2
Fiat G.55/I Centauro 	43 Feb 	Italy 	5.12 	1330	3 * 20 mm MG 151/20,
2 * 12.7 mm Breda-SAFAT
Reggiane Re.2005 Saggitario 	43 Feb 	Italy 	5.12 	1330	3 * 20 mm MG 151/20,
2 * 12.7 mm Breda-SAFAT
Kawanishi N1K1-J Shiden 	43 Jul 	Japan (N) 	2.11 	820	4 * 20 mm Type 99-2
Kawasaki Ki.61-I-Otsu 	43 Sep 	Japan (A) 	3.69 	1080	2 * 12.7 mm Ho-103,
2 * 20 mm MG 151/20
Bell P-63A-1 Kingcobra 	43 Oct 	USA 	2.63 	1180	1 * 37 mm M4,
4 * 12.7 mm Browning .50 M2
Yakovlev Yak-3 	43 Oct 	USSR 	2.64 	1080	1 * 20 mm ShVAK,
2 * 12.7 mm UBS
Supermarine Spitfire Mk.XIV 	44 Jan 	Britain 	2.24 	1250	2 * 20 mm Hispano Mk.II,
4 * 7.7 mm Browning .303
Kawakaki Ki.61-I-KAI-Hei 	44 Jan 	Japan 	3.95 	1310	2 * 20 mm Ho-5 (120),
2 * 12.7 mm Ho-103 (200)
Lavochkin La-7 	44 Feb 	USSR 	3.84 	1420	3 * 20 mm B-20
Hawker Tempest Mk.V 	44 Apr 	Britain 	6.50 	2300	4 * 20 mm Hispano Mk.V (200)
Nakajima Ki.84-I-Ko Hayate 	44 Apr 	Japan (A) 	3.95 	1310	2 * 20 mm Ho-5 (150),
2 * 12.7 mm Ho-103 (350)
Kawanishi N1K2-J Shiden-KAI 	44 Jul 	Japan (N) 	2.11 	820	4 * 20 mm Type 99-2
Lockheed P-38L Lightning 	44 Jul 	USA 	3.73 	1420	1 * 20 mm Hispano,
4 * 12.7 mm Browning .50 M2
Messerschmitt Me 262 	44 Jul 	Germany 	12.48 	1590	2 * 30 mm MK 108 (100),
2 * 30 mm MK 108 (80)
Focke-Wulf Fw 190D-9 	44 Aug 	Germany 	3.87 	1000	2 * 13 mm MG 131,
2 * 20 mm MG 151/20
Gloster Meteor Mk.III 	44 Sep 	Britain 	5.20 	2010	4 * 20 mm Hispano Mk.III
Messerschmitt Bf 109K-4 	44 Oct 	Germany 	4.16 	670	1 * 30 mm MK 108,
2 * 13 mm MG 131
Mitsubishi A6M5-Hei Reisen 	44 Nov 	Japan (N) 	3.49 	1060	2 * 20 mm Type 99-2,
3 * 13.2 mm Type 3
Republic P-47M Thunderbolt 	44 Dec 	USA 	4.85 	1830	8 * 12.7 mm Browning .50 M2
Kawakaki Ki.61-I-KAI-Tei 	44 Late 	Japan (A) 	7.51 	1510	2 * 30 mm Ho-155,
2 * 12.7 mm Ho-103
Messerschmitt Bf 109K-6 	44 Oct 	Germany 	10.40 	1470	3 * 30 mm MK 108,
2 * 13 mm MG 131
Lockheed P-80A Shooting Star 	45 Feb 	USA 	3.88 	1370	6 * 12.7 mm Browning .50 M2
Supermarine Spitfire Mk.21 	45 Apr 	Britain 	5.20 	2010	4 * 20 mm Hispano Mk.II
Ryan FR-1 Fireball 	45 May 	USA 	2.75 	920	4 * 12.7 mm Browning M2
Kawasaki Ki.100-I-Otsu 	45 Jun 	Japan (A) 	3.95 	1310	2 * 12.7 mm Ho-103 (250),
2 * 20 mm Ho-5 (250)
Mikoyan-Gurevich MiG-13 	45 Nov 	USSR 	3.84 	1420	3 * 20 mm B-20
Vought F4U-5 Corsair 	46 Apr 	USA 	7.37 	2600	4 * 20 mm Hispano M3
Mikoyan-Gurevich MiG-9 	46 Oct 	USSR 	8.69 	2070	1 * 37 mm N-37,
2 * 23 mm NS-23
McDonnell FH-1 Phantom 	46 Oct 	USA 	2.59 	920	4 * 12.7 mm Browning .50 M2
Lavochkin La-7 	47 Feb 	USSR 	7.32 	1740	4 * 23 mm NS-23
Yakovlev Yak-15 	47 May 	USSR 	3.66 	870	2 * 23 mm NS-23
Republic F-84B Thunderjet 	47 Aug 	USA 	5.82 	1940	6 * 12.7 mm Browning .50 M3
Yakovlev Yak-17 	47 Late 	USSR 	3.66 	870	2 * 23 mm NS-23
North American FJ-1 Fury 	48 Mar 	USA 	5.82 	2200	6 * 12.7 mm Browning .50 M3
North American F-86A Sabre 	48 May 	USA 	5.82 	2200	6 * 12.7 mm Browning .50 M3
McDonnell F2H-1 Banshee 	48 Aug 	USA 	7.37 	2600	4 * 20 mm Hispano M3
Mikoyan-Gurevich MiG-15 	48 Dec 	USSR 	8.69 	2070	1 * 37 mm N-37,
2 * 23 mm NS-23
Yakovlev Yak-23 	49 Early	USSR 	3.66 	870	2 * 23 mm NS-23
Vought F6U-1 Pirate 	49 Mar 	USA 	7.37 	2600	4 * 20 mm Hispano M3
Grumman F9F-2 Panther 	49 May 	USA 	7.37 	2600	4 * 20 mm Hispano M3
Lavochkin La-15 	49 Late 	USSR 	3.66 	870	2 * 23 mm NS-23
Lockheed F-94A 	50 May 	USA 	3.88 	1470	4 * 12.7 mm Browning .50 M3
Northrop F-89A Scorpion 	50 Sep 	USA 	11.05 	3900	6 * 20 mm M24
A.W. Meteor NF Mk.11 	50 Nov 	Britain 	6.50 	2300	4 * 20 mm Hispano Mk.V (160)
de Havilland Venom 	51 Jun 	Britain 	6.50 	2300	4 * 20 mm Hispano Mk.V
Supermarine Attacker 	51 Aug 	Britain 	6.50 	2300	4 * 20 mm Hispano Mk.V
Grumman F9F-6 Cougar 	51 Dec 	USA 	7.37 	2600	4 * 20 mm Hispano M3
North American F-86F Sabre 	52 Mar 	USA 	5.82 	2200	6 * 12.7 mm Browning .50 M3
Supermarine Swift F Mk.1 	52 Aug 	Britain 	9.53 	2970	2 * 30 mm Aden
Avro Canada CF-100 Mk.3 	52 Sep 	Canada 	7.76 	2200	8 * 12.7 mm Browning .50 M3
Mikoyan-Gurevich MiG-17 	52 Oct 	USSR 	11.37 	2710	1 * 37 mm N-37,
2 * 23 mm NR-23
North American FJ-2 Fury 	52 Nov 	USA 	7.32 	3740	4 * 20 mm Mk.12
Hawker Hunter F.1 	53 May 	Britain 	19.06 	5950	4 * 30 mm Aden
North American F-86H Sabre 	53 Sep 	USA 	11.44 	6070	4 * 20 mm M39
Yakovlev Yak-25 	53 Late 	USSR 	10.03 	2400	2 * 37 mm N-37L
Republic F-84F Thunderstreak 	54 Jan 	USA 	5.82 	2200	6 * 12.7 mm Browning .50 M3
Dassault Mystere IVA 	54 May 	France 	11.90 	5550	2 * 30 mm DEFA 541
Douglas F4D-1 Skyray 	54 Jun 	USA 	7.32 	3740	4 * 20 mm Mk.12
Gloster Javelin FAW Mk.1 	54 Jul 	Britain 	19.06 	5948	4 * 30 mm Aden
North American FJ-4 Fury 	54 Oct 	USA 	7.32 	3740	4 * 20 mm Mk.12
Canadair CL-13B Sabre 6 	54 Nov 	Canada 	5.82 	2198	6 * 12.7 mm Browning .50 M3
North American F-100C Super Sabre 	55 Jan 	USA 	11.44 	6072	4 * 20 mm M39
McDonnell F3H-2 Demon 	55 Apr 	USA 	7.32 	3740	4 * 20 mm Mk.12
North American F-86K Sabre 	55 May 	USA 	7.37 	2600	4 * 20 mm M24
Mikoyan-Gurevich MiG-19 	56 Mid 	USSR 	18.45 	5610	3 * 30 mm NR-30
Supermarine Scimitar 	57 Jan 	Britain 	9.53 	5948	4 * 30 mm Aden
Vought F8U-1 Crusader 	57 Mar 	USA 	7.32 	3740	4 * 20 mm Mk.12
Grumman F11F-1 Tiger 	57 May 	USA 	7.32 	3740	4 * 20 mm Mk.12
Dassault Super Mystere B.2 	57 May 	France 	11.90 	2000	2 * 30 mm DEFA 30M552
McDonnell F-101C Voodoo 	57 Aug 	USA 	11.44 	6072	4 * 20 mm M39
Republic F-105B Thunderchief 	58 May 	USA 	11.11 	5950	1 * 20 mm M61A1
Lockheed F-104A Starfighter 	58 Dec 	USA 	6.73 	3600	1 * 20 mm M61
English Electric Lightning F Mk.1 	59 Oct 	Britain 	9.53 	2974	2 * 30 mm Aden
Mikoyan-Gurevich MiG-21F 	59 Late 	USSR 	12.30 	3740	2 * 30 mm NR-30
Sukhoi Su-7B 	60 Early	USSR 	12.30 	3740	2 * 30 mm NR-30
Dassault Mirage IIIC 	60 Oct 	France 	11.90 	2000	2 * 30 mm DEFA 30M552
Northrop F-5A Freedom Fighter 	63 Oct 	USA 	5.72 	3036	2 * 20 mm M39
Dassault Mirage IIIE 	64 Jan 	France 	11.90 	2000	2 * 30 mm DEFA 30M552
Mikoyan-Gurevich MiG-21PFM 	64 Mid 	USSR 	11.33 	3100	1 * 23 mm GSh-23L
Dassault Mirage F.1 	69 Mar 	France 	11.90 	2000	2 * 30 mm DEFA 30-553
Mikoyan-Gurevich MiG-23M 	70 Late 	USSR 	11.33 	3100	1 * 23 mm GSh-23L
Mikoyan-Gurevich MiG-21bis 	72 Feb 	USSR 	11.33 	3100	1 * 23 mm GSh-23L
Grumman F-14 Tomcat 	72 Oct 	USA 	11.11 	5950	1 * 20 mm M61A1
Northrop F-5E Tiger II 	73 Mid 	USA 	5.72 	3036	2 * 20 mm M39
McDonnell F-15A Eagle 	74 Nov 	USA 	11.11 	5950	1 * 20 mm M61A1
Saab JA37 Viggen 	77 Nov 	Sweden 	8.10 	4300	1 * 30 mm Oerlikon KCA
General Dynamics F-16A 	78 Aug 	USA 	11.11 	5950	1 * 20 mm M61A1
Dassault Mirage 2000C 	82 Nov 	France 	16.50 	2770	2 * 30 mm GIAT 30-554
Mikoyan-Gurevich MiG-31 	82 Late 	USSR 	26.67 	7300	1 * 23 mm GSh-6-23
Mikoyan-Gurevich MiG-29 	82 Late 	USSR 	12.00 	4750	1 * 30 mm GSh-301 (100)
McDonnell F/A-18A Hornet 	83 Jan 	USA 	11.11 	5950	1 * 20 mm M61A1 (570)
Panavia Tornado F.3 	85 Nov 	Britain 	7.37 	3870	1 * 27 mm BK 27
Saab JAS39 Gripen 	93 May 	Sweden 	7.37 	3870	1 * 27 mm BK 27
Sukhoi Su-27 		USSR 	7.37 	4750	1 * 30 mm GSh-301 (150)