What is the max case length for this cartridge? Just don't want to over trim my brass....

Couldn't find anything by googling it but the 7 SAUM has a max of 2.0036 and a minimum of 2.0012.

I usually either use the Lee spud or find the shortest case after squaring up the mouth and then trim all to that length if it is not excessively short.

The best way is to measure with a cartridge insert. Forster and others make these to tell you where your chamber mouth is.

A flat base bullet can be used backwards but it is easier to get a false measurement with this method.

Trim to 2.025 (2.035 max)

This^. Remember though, .300 SAUM brass will finish shorter than 7 SAUM brass if you're sizing it down and turning necks.

If you really want to know what the trim length should be for your chamber you can buy a little top hat shaped plug that would seat in a modified case and give you the base to end of neck dimension for your specific chamber. You simply chamber the modified case with the gage in it and measure the resulting OAL. Sinclair lists them as chamber length gages. I make my own. I've found several of my factory chambers to be longer than expected and have adjusted my trim length to accommodate them.

That's what I do as well, my chamber ended up at 2.042 measured with the modified case and Sinclair. My brass on its 3rd and fourth firing is all at about 2.025 right now. Actually started a hair below minimum from the get-go with reformed 7 SAUM brass.

Thanks for the heads up. I will order the Sinclair gauges for several different calibers as they are minimal cost. I don't know w here I got the idea, but I just assumed the case length would have been the same as the 300 SAUM.