I had actually posted this years ago but for some reason the photos no longer exist. I've updated some info. I mostly collect British Canadian these days as I can't afford German any more.
The first photo is a M1907 Bavarian Feldrock to the 3rd FussArtillerie. It actually started out as a Feldrock to the 19th Bav. IR but was expertly converted when the 3rd FAR was raised and then supplied to that unit. This is the Feldrock type (given Corp, Cuff and state distinction differences) that the German army wore when it marched in 1914. Note the Lining (Futter) which is the standard for pre-war/war start Feldrocks.
This feldrock also has a Kaiserabzeichen Fur Artillerie (sometimes known as a Konigpriz)
The next photo shows Brandenburg cuff details with Bav. buttons.
In 1913 the Landsturm was aproved to wear the Feldrock with simplified "Futter" lining. This type of Feldrock was approved for the entire army in Sept 1914 (at least Prussia, Saxony and Wurtemburg--edit---Bavaria adopted in Oct 1914).
The next photos show "Futter" detail deferences between the M1907 on top and the M1913 Feldrocks. The middle one is an actual 1913 Infantry well abused by a costume house.
The next photo shows the outside differences between the Pioneer Battalion M1913 Feldrock with Swedish cuffs and an Infantry version which unfortunately has been abused by a costume house.
The next photo shows cuff closing diferences between the M1907 (top) and M1913 (bottom).
Note only the Landsturn would have had a cuff like the M1913 until Sept 1914--after that time the entire army.
These types of Feldrocks arte commonly called M 1907/1910. As far as I can tell from German sources this is very incorrected and a designation that did not exist. I think this is confused with Officers regulation uniforms which do have a Model 1910 version.
The next photo shows a Shirt--I assume Bav 1st Corps as it was made in Bavaria and is marked to the 1st Corps. It is made of trico fabric. A pair of M1915 tuchhose dated 1918 from the Guard Corps Clothing Depot and a M1915 Bluse from the Machinegun Company of 139th IR (Saxon).
The last photo shows a M1908 Mantel from the 2nd Grenadier Regiment dated 1913 and 1914. This is of Grau cloth and unfortunately the Infantry collar signs have been removed. It has all the original smooth copper buttons on it. The coat on the right is the (Einheitsmantel) M1915.
There were a few questions about Bavarian Buttons on these coats. There was actually no such thing and if found were added later or an anomaly. The M1915 regulations adopted by Bavaria (adopted 1 April 1916) actually calls out common crown buttons for the Mantel with collar made of the smae material as the rest of the coat.