If I do reload this in VDub again it comes up 23.976 however here's more information on the file:
Code:
General
Count : 291
Count of stream of this kind : 1
Kind of stream : General
Kind of stream : General
Stream identifier : 0
Inform : Matroska: 18.4 GiB, 1h 38mn
Unique ID : 239127260858190402181820675171044581556
Unique ID : 239127260858190402181820675171044581556 (0xB3E63C376AF5933DB088DDC34D0C60B4)
Count of video streams : 1
Video_Format_List : AVC
Video_Format_WithHint_List : AVC
Codecs Video : AVC
Video_Language_List : English
Complete name : D:\Conversion\1 - Pre\Mike.mkv
Folder name : D:\Conversion\1 - Pre\Mike
File name : Mike
File extension : mkv
Format : Matroska
Format : Matroska
Format/Url : http://packs.matroska.org/
Format/Extensions usually used : mkv mk3d mka mks
Commercial name : Matroska
Format version : Version 4 / Version 2
Codec : Matroska
Codec : Matroska
Codec/Url : http://packs.matroska.org/
Codec/Extensions usually used : mkv mk3d mka mks
File size : 19792777397
File size : 18.4 GiB
File size : 18 GiB
File size : 18 GiB
File size : 18.4 GiB
File size : 18.43 GiB
Duration : 5912615
Duration : 1h 38mn
Duration : 1h 38mn 32s 615ms
Duration : 1h 38mn
Duration : 01:38:32.615
Overall bit rate mode : VBR
Overall bit rate mode : Variable
Overall bit rate : 26780404
Overall bit rate : 26.8 Mbps
Stream size : 393856830
Stream size : 376 MiB (2%)
Stream size : 376 MiB
Stream size : 376 MiB
Stream size : 376 MiB
Stream size : 375.6 MiB
Stream size : 376 MiB (2%)
Proportion of this stream : 0.01990
Title : Mike
Movie name : Mike
Encoded date : UTC 2016-11-02 15:28:27
File creation date : UTC 2016-11-02 15:28:27.794
File creation date (local) : 2016-11-02 10:28:27.794
File last modification date : UTC 2016-11-02 15:33:37.680
File last modification date (local) : 2016-11-02 10:33:37.680
Writing application : mkvmerge v6.6.0 ('The Edge Of The In Between') built on Dec 1 2013 17:55:00
Writing library : libebml v1.3.0 + libmatroska v1.4.1
Writing library : libebml v1.3.0 + libmatroska v1.4.1
Attachements : cover_land.jpg / small_cover.jpg / small_cover_land.jpg / cover.jpg
Video
Count : 277
Count of stream of this kind : 1
Kind of stream : Video
Kind of stream : Video
Stream identifier : 0
StreamOrder : 0
Inform : English, 26.2 Mbps, 1920*1080 (16:9), at 23.976 fps, AVC (High@L4.1) (CABAC / 2 Ref Frames)
ID : 1
ID : 1
Unique ID : 1
Format : AVC
Format/Info : Advanced Video Codec
Format/Url : http://developers.videolan.org/x264.html
Commercial name : AVC
Format profile : High@L4.1
Format settings : CABAC / 2 Ref Frames
Format settings, CABAC : Yes
Format settings, CABAC : Yes
Format settings, ReFrames : 2
Format settings, ReFrames : 2 frames
Internet media type : video/H264
Codec ID : V_MPEG4/ISO/AVC
Codec ID/Url : http://ffdshow-tryout.sourceforge.net/
Codec : V_MPEG4/ISO/AVC
Codec : AVC
Codec/Family : AVC
Codec/Info : Advanced Video Codec
Codec/Url : http://ffdshow-tryout.sourceforge.net/
Codec profile : High@L4.1
Codec settings : CABAC / 2 Ref Frames
Codec settings, CABAC : Yes
Codec_Settings_RefFrames : 2
Duration : 5912621
Duration : 1h 38mn
Duration : 1h 38mn 32s 621ms
Duration : 1h 38mn
Duration : 01:38:32.621
Bit rate mode : VBR
Bit rate mode : Variable
Bit rate : 26247474
Bit rate : 26.2 Mbps
Width : 1920
Width : 1 920 pixels
Height : 1080
Height : 1 080 pixels
Pixel aspect ratio : 1.000
Display aspect ratio : 1.778
Display aspect ratio : 16:9
Frame rate mode : CFR
Frame rate mode : Constant
Frame rate : 23.976
Frame rate : 23.976 fps
Frame count : 141761
Resolution : 8
Resolution : 8 bits
Colorimetry : 4:2:0
Color space : YUV
Chroma subsampling : 4:2:0
Bit depth : 8
Bit depth : 8 bits
Scan type : Progressive
Scan type : Progressive
Interlacement : PPF
Interlacement : Progressive
Bits/(Pixel*Frame) : 0.528
Delay : 0
Delay : 00:00:00.000
Delay, origin : Container
Delay, origin : Container
Stream size : 19398920567
Stream size : 18.1 GiB (98%)
Stream size : 18 GiB
Stream size : 18 GiB
Stream size : 18.1 GiB
Stream size : 18.07 GiB
Stream size : 18.1 GiB (98%)
Proportion of this stream : 0.98010
Title : Mike
Language : en
Language : English
Language : English
Language : en
Language : eng
Language : en
Default : No
Default : No
Forced : No
Forced : No
Buffer size : 30000000 / 30000000
Based on this is a constant frame rate.