Howdy Jaeger and welcome to the club.
Congrats on the 835, is it new or used? if it's new, it will surely be stiff and it should loosen up.
http://www.mossberg.com/manuals/500_835 ... 5_en_o.pdf
if it's used, you might need to give it a
real good cleaning.(take it apart again, i'm sorry) look at the bolt and see if there's any nicks or pitting, also where it seats, check to see if it's smooth. when you have it apart, slide the bolt with your finger back and forth the way it travels to see if it's sliding smoothly. if it is,.. good, if not, wherever the lag is when you slide it look closely to see what is making it lag in that area. use some wet/dry 600 sand paper and a drop or two of lube oil to smooth it out. you might be able to use a small wire brush instead in that area.
also check the action slide bar to see if the bars are straight, and the receiver cuts (with a flashlight) , to see if there's gunk or pitting/rust inside..use a small flat hobby file to get rid of the rust or sand paper folded up to fit and use it like you would shine a shoe...back n forth...
also check the elevator. make sure it's straight as well and slides smoothly with your finger up and down.
oh..and if you have any pics of it we'd love to see it. either here or in this area,
viewforum.php?f=33
let me know how it goes, and i look forward to seeing more of you here....