Need Dye Dm5 bolt help.

[Calvin]

I am rebuilding a friend's DM5. It was placed in storage around 2008. It was in a climate controlled area, but I am replacing all seals. I had 4 gooey urethane seals to clean out, but only one thing has really been an issue. The rebuild videos that I am watching show the bolt being pretty loose moving front to back inside the can. My bolt has a slightly raised portion on the section of the bolt that rides through the rear inner tophat oring, which is an 013 buna.





The raised portion does not look like wear of any kind. It seems to be machined there on purpose with a smooth leadup before and after. However, when that section pushed past that rear inner top hat oring, it stiffens up and pushes through with increased force and a subtle click. Is my buna 70 just a smidge oversized? What am I missing here?

[mercpb]

sometimes the urethane degrades to a coating and tightens tolerances and sometimes you can't see this inside the bolt housing -- you can soak aluminum parts in acetone 30min and the otherwise hardened urethane 'shellac' wipes/rinses right off.

if you're experiencing unusual tightness you might want to give this a go.

the area you're describing sounds normal to me, I think it's oring related.

[Calvin]

Thank you. The old oring that came out of there was buna. Will check for older residue and then try other brands of 013.